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EventTarget.addEventListener() - Web APIs
the eventtarget method addeventlistener() sets up a function that will be called whenever the specified event is delivered to the target.
... addeventlistener() works by adding a function or an object that implements eventlistener to the list of event listeners for the specified event type on the eventtarget on which it's called.
... syntax target.addeventlistener(type, listener [, options]); target.addeventlistener(type, listener [, usecapture]); target.addeventlistener(type, listener [, usecapture, wantsuntrusted ]); // gecko/mozilla only parameters type a case-sensitive string representing the event type to listen for.
...And 34 more matches
Color picker tool - CSS: Cascading Style Sheets
otype.getcolor = function getcolor() { if (this.a | 0 === 1) return this.gethexa(); return this.getrgba(); }; /*=======================================================================*/ /*=======================================================================*/ /*========== capture mouse movement ==========*/ var setmousetracking = function setmousetracking(elem, callback) { elem.addeventlistener('mousedown', function(e) { callback(e); document.addeventlistener('mousemove', callback); }); document.addeventlistener('mouseup', function(e) { document.removeeventlistener('mousemove', callback); }); }; /*====================*/ // color picker class /*====================*/ function colorpicker(node) { this.color = new color(); this.node = node; this.subscribers = [...
...r = document.createelement('div'); var input = document.createelement('input'); var info = document.createelement('span'); wrapper.classname = 'input'; wrapper.setattribute('data-topic', topic); info.textcontent = title; info.classname = 'name'; input.setattribute('type', 'text'); wrapper.appendchild(info); wrapper.appendchild(input); this.node.appendchild(wrapper); input.addeventlistener('change', onchangefunc); input.addeventlistener('click', function() { this.select(); }); this.subscribe(topic, function(value) { input.value = value; }); }; colorpicker.prototype.createchangemodebutton = function createchangemodebutton() { var button = document.createelement('div'); button.classname = 'switch_mode'; button.addeventlistener('click', function() { if (thi...
...cribe : unsubscribe, setpickermode : setpickermode }; })(); /** * ui-slidersmanager */ var inputslidermanager = (function inputslidermanager() { var subscribers = {}; var sliders = []; var inputcomponent = function inputcomponent(obj) { var input = document.createelement('input'); input.setattribute('type', 'text'); input.style.width = 50 + obj.precision * 10 + 'px'; input.addeventlistener('click', function(e) { this.select(); }); input.addeventlistener('change', function(e) { var value = parsefloat(e.target.value); if (isnan(value) === true) setvalue(obj.topic, obj.value); else setvalue(obj.topic, value); }); return input; }; var slidercomponent = function slidercomponent(obj, sign) { var slider = document.createelement('div'); var startx = nu...
...And 16 more matches
Linear-gradient Generator - CSS: Cascading Style Sheets
otype.getcolor = function getcolor() { if (this.a | 0 === 1) return this.gethexa(); return this.getrgba(); }; /*=======================================================================*/ /*=======================================================================*/ /*========== capture mouse movement ==========*/ var setmousetracking = function setmousetracking(elem, callback) { elem.addeventlistener('mousedown', function(e) { callback(e); document.addeventlistener('mousemove', callback); }); document.addeventlistener('mouseup', function(e) { document.removeeventlistener('mousemove', callback); }); }; /*====================*/ // color picker class /*====================*/ function colorpicker(node) { this.color = new color(); this.node = node; this.subscribers = [...
...r = document.createelement('div'); var input = document.createelement('input'); var info = document.createelement('span'); wrapper.classname = 'input'; wrapper.setattribute('data-topic', topic); info.textcontent = title; info.classname = 'name'; input.setattribute('type', 'text'); wrapper.appendchild(info); wrapper.appendchild(input); this.node.appendchild(wrapper); input.addeventlistener('change', onchangefunc); input.addeventlistener('click', function() { this.select(); }); this.subscribe(topic, function(value) { input.value = value; }); }; colorpicker.prototype.createchangemodebutton = function createchangemodebutton() { var button = document.createelement('div'); button.classname = 'switch_mode'; button.addeventlistener('click', function() { if (thi...
...child !== null) { option = node.firstelementchild; option_value = option.getattribute('data-value'); if (option_value === null) option.setattribute('data-value', uval); list.appendchild(node.firstelementchild); uval++; } node.appendchild(select); node.appendchild(list); select.onclick = this.toggle.bind(this); list.onclick = this.updatevalue.bind(this); document.addeventlistener('click', clickout); this.state = 0; this.time = 0; this.dropmenu = list; this.select = select; this.toggle(false); this.value = {}; this.topic = topic; if (label) select.textcontent = label; else this.setnodevalue(list.children[selected]); dropdowns[topic] = this; }; dropdown.prototype.toggle = function toggle(state) { if (typeof(state) === 'boolean') this.st...
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Sending forms through JavaScript - Learn web development
urlencodeddata = urlencodeddatapairs.join( '&' ).replace( /%20/g, '+' ); // define what happens on successful data submission xhr.addeventlistener( 'load', function(event) { alert( 'yeah!
... data sent and response loaded.' ); } ); // define what happens in case of error xhr.addeventlistener( 'error', function(event) { alert( 'oops!
... xhr.send( urlencodeddata ); } btn.addeventlistener( 'click', function() { senddata( {test:'ok'} ); } ) here's the live result: note: this use of xmlhttprequest is subject to the same-origin policy if you want to send data to a third party web site.
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Border-image generator - CSS: Cascading Style Sheets
: break-all; float: left; } javascript content 'use strict'; /** * ui-slidersmanager */ var inputslidermanager = (function inputslidermanager() { var subscribers = {}; var sliders = []; var inputcomponent = function inputcomponent(obj) { var input = document.createelement('input'); input.setattribute('type', 'text'); input.style.width = 50 + obj.precision * 10 + 'px'; input.addeventlistener('click', function(e) { this.select(); }); input.addeventlistener('change', function(e) { var value = parsefloat(e.target.value); if (isnan(value) === true) setvalue(obj.topic, obj.value); else setvalue(obj.topic, value); }); return input; }; var slidercomponent = function slidercomponent(obj, sign) { var slider = document.createelement('div'); var startx = nu...
...ll; var start_value = 0; slider.addeventlistener("click", function(e) { document.removeeventlistener("mousemove", slidermotion); setvalue(obj.topic, obj.value + obj.step * sign); }); slider.addeventlistener("mousedown", function(e) { startx = e.clientx; start_value = obj.value; document.body.style.cursor = "e-resize"; document.addeventlistener("mouseup", slideend); document.addeventlistener("mousemove", slidermotion); }); var slideend = function slideend(e) { document.removeeventlistener("mousemove", slidermotion); document.body.style.cursor = "auto"; slider.style.cursor = "pointer"; }; var slidermotion = function slidermotion(e) { slider.style.cursor = "e-resize"; var delta = (e.clientx - startx) / obj.sensivity | 0; var value = delta * obj.step...
...child !== null) { option = node.firstelementchild; option_value = option.getattribute('data-value'); if (option_value === null) option.setattribute('data-value', uval); list.appendchild(node.firstelementchild); uval++; } node.appendchild(select); node.appendchild(list); select.onclick = this.toggle.bind(this); list.onclick = this.updatevalue.bind(this); document.addeventlistener('click', clickout); this.state = 0; this.time = 0; this.dropmenu = list; this.select = select; this.toggle(false); this.value = {}; this.topic = topic; if (label) select.textcontent = label; else this.setnodevalue(list.children[selected]); dropdowns[topic] = this; }; dropdown.prototype.toggle = function toggle(state) { if (typeof(state) === 'boolean') this.st...
...And 11 more matches
Index - Web APIs
WebAPIIndex
1275 eventtarget.addeventlistener() api, accessouterdata, dom, detecting events, event handlers, event listener, eventtarget, javascript, method, passingdata, receiving events, reference, addeventlistener, attachevent, events, mselementresize the eventtarget method addeventlistener() sets up a function that will be called whenever the specified event is delivered to the target.
... 1278 eventtarget.removeeventlistener() api, dom, dom element methods, eventtarget, gecko, method, reference, browser compatibility, removeeventlistener the eventtarget.removeeventlistener() method removes from the eventtarget an event listener previously registered with eventtarget.addeventlistener().
...this method is only needed when using eventtarget.addeventlistener; it is implied when using messagechannel.onmessage.
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Cross-browser audio basics - Developer guides
myaudio.addeventlistener("loadstart", function() { //grabbing the file }); durationchange if you just want to know as soon as the duration of your media is established, this is the event for you.
... myaudio.addeventlistener("durationchange", function() { //you can display the duration now }); loadedmetadata metadata can consist of more than just duration — if you want to wait for all the metadata to download before doing something, you can detect the loadedmetadata event.
... myaudio.addeventlistener("loadedmetadata", function() { //you can display the duration now }); loadeddata the loadeddata event is fired when the first bit of media arrives.
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Interacting with page scripts - Archive of obsolete content
expose objects to page scripts until firefox 30, you could use unsafewindow to perform the reverse procedure, and make objects defined in content scripts available to page scripts: // content-script.js unsafewindow.contentscriptobject = {"greeting" : "hello from add-on"}; // page-script.js var button = document.getelementbyid("show-content-script-var"); button.addeventlistener("click", function() { // access object defined by content script console.log(window.contentscriptobject.greeting); // "hello from add-on" }, false); after firefox 30, you can still do this for primitive values, but can no longer do it for objects.
...tons and assigns an event listener to each: one listener displays a property of the cloned object, and the other listener displays a property of the assigned object: <html> <head> </head> <body> <input id="works" type="button" value="i will work"/> <input id="fails" type="button" value="i will not work"/> <script> var works = document.getelementbyid("works"); works.addeventlistener("click", function() { alert(clonedcontentscriptobject.greeting); }, false); var fails = document.getelementbyid("fails"); fails.addeventlistener("click", function() { alert(assignedcontentscriptobject.greeting); }, false); </script> </body> </html> if you run the example, clicking "i will work" displays the value of "greeting" in an alert.
...etme(user) { return salutation + user; } exportfunction(greetme, unsafewindow, {defineas: "greetme"}); finally, the "page.html" file adds a button and a page script that calls the exported function when the user pushes the button: <html> <head> </head> <body> <input id="test" type="button" value="click me"/> <script> var test = document.getelementbyid("test"); test.addeventlistener("click", function() { alert(window.greetme("page script")); }, false); </script> </body> </html> exportfunction() works by structured cloning the arguments and return value of the function from one scope to the other.
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How to build custom form controls - Learn web development
window.addeventlistener("load", function () { document.body.classlist.remove("no-widget"); document.body.classlist.add("widget"); }); without js with js check out the source code note: if you really want to make your code generic and reusable, instead of doing a class switch it's far better to just add the widget class to hide the <select> elements, and to dynamically ...
...the features we plan to use are the following: classlist addeventlistener() foreach queryselector() and queryselectorall() beyond the availability of those specific features, there is still one issue remaining before starting.
...window.addeventlistener('load', function () { var selectlist = document.queryselectorall('.select'); // each custom control needs to be initialized selectlist.foreach(function (select) { // as well as all its `option` elements var optionlist = select.queryselectorall('.option'); // each time a user hovers their mouse over an option, we highlight the given option optionlist.foreach(function (opti...
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HTML text fundamentals - Learn web development
: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var solution = document.getelementbyid('solution'); var output = document.queryselector('.output'); var code = textarea.value; var userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...w solution'; } updatecode(); }); var htmlsolution = '<h1>my short story</h1>\n<p>i am a statistician and my name is trish.</p>\n<p>my legs are made of cardboard and i am married to a fish.</p>'; var solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { var scrollpos = textarea.scrolltop; var caretpos = textarea.selectionstart; var front = (textarea.value).substring(0, caretpos); var back = (textarea.value).substring(textarea.selec...
...: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var solution = document.getelementbyid('solution'); var output = document.queryselector('.output'); var code = textarea.value; var userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
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Introduction to events - Learn web development
addeventlistener() and removeeventlistener() the newest type of event mechanism is defined in the document object model (dom) level 2 events specification, which provides browsers with a new function — addeventlistener().
...we could rewrite our random color example to look like this: const btn = document.queryselector('button'); function bgchange() { const rndcol = 'rgb(' + random(255) + ',' + random(255) + ',' + random(255) + ')'; document.body.style.backgroundcolor = rndcol; } btn.addeventlistener('click', bgchange); note: you can find the full source code for this example on github (also see it running live).
... inside the addeventlistener() function, we specify two parameters — the name of the event we want to register this handler for, and the code that comprises the handler function we want to run in response to it.
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Using the Browser API
MozillaGeckoChromeAPIBrowser APIUsing
the javascript implementation to wire up the functionality required by our simple browser, we've written some basic javascript (see the full javascript listing.) wiring up the back and forward buttons early on in the code we implement two simple event listeners to move the browser back and forward in history when the relevant buttons are pressed: back.addeventlistener('touchend',function() { browser.goback(); }); fwd.addeventlistener('touchend',function() { browser.goforward(); }); the functions can be handled using the browser api htmliframeelement.goback() and htmliframeelement.goforward() methods.
...when you press the keyboard's return button, the 'submit' event is fired, which we handle like this: urlform.addeventlistener('submit',function(e) { e.preventdefault(); browser.src = urlbar.value; urlbar.blur(); }); we first call preventdefault() to stop the form just submitting and reloading the page — which is really not what we want.
... browser.addeventlistener('mozbrowserlocationchange', function (e) { urlbar.value = e.detail; }); zooming in and out the browser content can be programmatically zoomed in and out using the htmliframeelement.zoom() method.
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Box-shadow generator - CSS: Cascading Style Sheets
i-slider-pointer'; node.appendchild(pointer); this.pointer = pointer; setmousetracking(node, updateslider.bind(this)); sliders[topic] = this; setvalue(topic, this.value); } var setbuttoncomponent = function setbuttoncomponent(node) { var type = node.getattribute('data-type'); var topic = node.getattribute('data-topic'); if (type === "sub") { node.textcontent = '-'; node.addeventlistener("click", function() { decrement(topic); }); } if (type === "add") { node.textcontent = '+'; node.addeventlistener("click", function() { increment(topic); }); } } var setinputcomponent = function setinputcomponent(node) { var topic = node.getattribute('data-topic'); var unit_type = node.getattribute('data-unit'); var input = document.createelement('input'); v...
...ar unit = document.createelement('span'); unit.textcontent = unit_type; input.setattribute('type', 'text'); node.appendchild(input); node.appendchild(unit); input.addeventlistener('click', function(e) { this.select(); }); input.addeventlistener('change', function(e) { setvalue(topic, e.target.value | 0); }); subscribe(topic, function(value) { node.children[0].value = value; }); } var increment = function increment(topic) { var slider = sliders[topic]; if (slider === null || slider === undefined) return; if (slider.value + slider.step <= slider.max) { slider.value += slider.step; setvalue(slider.topic, slider.value) notify.call(slider); } }; var decrement = function decrement(topic) { var slider = sliders[topic]; if (slider === null || slider ...
...var delta = slider.max - slider.min; var width = slider.node.clientwidth; var offset = slider.pointer.clientwidth; var pos = (value - slider.min) * width / delta; slider.value = value; slider.pointer.style.left = pos - offset / 2 + "px"; slider.node.setattribute('data-value', value); notify.call(slider); } var setmousetracking = function setmousetracking(elem, callback) { elem.addeventlistener("mousedown", function(e) { callback(e); document.addeventlistener("mousemove", callback); }); document.addeventlistener("mouseup", function(e) { document.removeeventlistener("mousemove", callback); }); } var subscribe = function subscribe(topic, callback) { if (subscribers[topic] === undefined) subscribers[topic] = []; subscribers[topic].push(callback); } var unsubscr...
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Creating a cross-browser video player - Developer guides
play/pause playpause.addeventlistener('click', function(e) { if (video.paused || video.ended) video.play(); else video.pause(); }); when a click event is detected on the play/pause button, the handler first of all checks if the video is currently paused or has ended (via the media api's paused and ended attributes); if so, it uses the play() method to playback the video.
... stop stop.addeventlistener('click', function(e) { video.pause(); video.currenttime = 0; progress.value = 0; }); the media api doesn't have a stop method, so to mimic this the video is paused, and its currenttime (i.e.
... mute mute.addeventlistener('click', function(e) { video.muted = !video.muted; }); the mute button is a simple toggle button that uses the media api's muted attribute to mute the video: this is a boolean indicating whether the video is muted or not.
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Interaction between privileged and non-privileged pages - Archive of obsolete content
var myextension = { mylistener: function(evt) { alert("received from web page: " + evt.target.getattribute("attribute1") + "/" + evt.target.getattribute("attribute2")); } } document.addeventlistener("myextensionevent", function(e) { myextension.mylistener(e); }, false, true); // the last value is a mozilla-specific value to indicate untrusted content is allowed to trigger the event.
...rface(components.interfaces.nsiinterfacerequestor) .getinterface(components.interfaces.nsiwebnavigation) .queryinterface(components.interfaces.nsidocshelltreeitem) .roottreeitem .queryinterface(components.interfaces.nsiinterfacerequestor) .getinterface(components.interfaces.nsidomwindow); mainwindow.document.addeventlistener("myextensionevent", function(e) { myextension.mylistener(e); }, false, true); if you need to to pass lots of data, consider using cdata sections instead of the simple attributes on a custom element.
... document.addeventlistener("message", function(e) { yourfunction(e); }, false, true); sending data from chrome to unprivileged document to "answer" the web page (e.g., return code), your extension can set an attribute or attach child elements on the event target element (<myextensiondataelement/> in this example).
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ui/frame - Archive of obsolete content
if the frame script initiates the conversation, you need to specify "*" as the origin: window.parent.postmessage("ping", "*"); if the frame script has received a message from the add-on already, it can use the origin property of the event object passed to the message hander: // listen for messages from the add-on, and send a reply window.addeventlistener("message", function(event) { event.source.postmessage("pong", event.origin) }, false); this frame script listens to change events on the "city-selector" <select> element, and sends a message to the add-on containing the value for the newly selected element.
... // city-info.js var cityselector = window.document.getelementbyid("city-selector"); cityselector.addeventlistener("change", citychanged); function citychanged() { window.parent.postmessage(cityselector.value, "*"); } to listen for these messages in the main add-on code, you can assign a listener to the frame's message event.
...foggy" } var frame = new frame({ url: "./city-info.html", onmessage: (e) => { updateweather(e.data); } }); var toolbar = toolbar({ name: "city-info", title: "city info", items: [frame] }); function updateweather(location) { frame.postmessage(weather[location], frame.url); } to listen to these messages in the frame script, add a listener to the window's message event: window.addeventlistener("message", updateweather, false); function updateweather(message) { var label = window.document.getelementbyid("weather"); label.textcontent = message.data; } from add-on to a specific frame you can send a message from the main add-on code to the frame hosted by a particular browser window.
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Looping code - Learn web development
canvas.height = height; function random(number) { return math.floor(math.random()*number); } function draw() { ctx.clearrect(0,0,width,height); for (let i = 0; i < 100; i++) { ctx.beginpath(); ctx.fillstyle = 'rgba(255,0,0,0.5)'; ctx.arc(random(width), random(height), random(50), 0, 2 * math.pi); ctx.fill(); } } btn.addeventlistener('click',draw); </script> </body> </html> you don't have to understand all the code for now, but let's look at the part of the code that actually draws the 100 circles: for (let i = 0; i < 100; i++) { ctx.beginpath(); ctx.fillstyle = 'rgba(255,0,0,0.5)'; ctx.arc(random(width), random(height), random(50), 0, 2 * math.pi); ctx.fill(); } random(x), defined earlier in the code,...
...sults in: <label for="search">search by contact name: </label> <input id="search" type="text"> <button>search</button> <p></p> now on to the javascript: const contacts = ['chris:2232322', 'sarah:3453456', 'bill:7654322', 'mary:9998769', 'dianne:9384975']; const para = document.queryselector('p'); const input = document.queryselector('input'); const btn = document.queryselector('button'); btn.addeventlistener('click', function() { let searchname = input.value.tolowercase(); input.value = ''; input.focus(); for (let i = 0; i < contacts.length; i++) { let splitcontact = contacts[i].split(':'); if (splitcontact[0].tolowercase() === searchname) { para.textcontent = splitcontact[0] + '\'s number is ' + splitcontact[1] + '.'; break; } else { para.textcontent = 'contact ...
...abel for="search">search by contact name: </label> <input id="search" type="text"> <button>search</button> <p></p> <script> const contacts = ['chris:2232322', 'sarah:3453456', 'bill:7654322', 'mary:9998769', 'dianne:9384975']; const para = document.queryselector('p'); const input = document.queryselector('input'); const btn = document.queryselector('button'); btn.addeventlistener('click', function() { let searchname = input.value.tolowercase(); input.value = ''; input.focus(); for (let i = 0; i < contacts.length; i++) { let splitcontact = contacts[i].split(':'); if (splitcontact[0].tolowercase() === searchname) { para.textcontent = splitcontact[0] + '\'s number is ' + splitcontact[1] + '.'; break; } else ...
...And 5 more matches
Communicating With Other Scripts - Archive of obsolete content
page scripts if a page includes its own scripts using <script> tags, either embedded in the page or linked to it using the src attribute, there are a couple of ways a content script can communicate with it: using the dom postmessage() api using custom dom events using the dom postmessage api note that before firefox 31 code in content scripts can't use window to access postmessage() and addeventlistener() and instead must use document.defaultview.
... finally, "listen.html" uses window.addeventlistener() to listen for messages from the content script: <!doctype html> <html> <head></head> <body> <script> window.addeventlistener('message', function(event) { window.alert(event.data); // message from content script }, false); </script> </body> </html> messaging from page script to content script sending messages from the page script to the content script is ju...
...age() to send the content script a message when the user clicks a button: <!doctype html> <html> <head></head> <body> <script> function sendmessage() { window.postmessage("message from page script", "http://my-domain.org/"); } </script> <button onclick="sendmessage()">send message</button> </body> </html> finally, the content script "listen.js" uses window.addeventlistener() to listen for messages from the page script: // listen.js window.addeventlistener('message', function(event) { console.log(event.data); // message from page script console.log(event.origin); }, false); using postmessage() before firefox 31 if your add-on is running in a version of firefox before firefox 31, then your content script can't access the postmessage() or addeventlistener()...
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Tabbed browser - Archive of obsolete content
// wrong way (the page hasn't finished loading yet) var newtabbrowser = gbrowser.getbrowserfortab(gbrowser.addtab("http://www.google.com/")); alert(newtabbrowser.contentdocument.body.innerhtml); // better way var newtabbrowser = gbrowser.getbrowserfortab(gbrowser.addtab("http://www.google.com/")); newtabbrowser.addeventlistener("load", function () { newtabbrowser.contentdocument.body.innerhtml = "<div>hello world</div>"; }, true); (the event target in the onload handler will be a 'tab' xul element).
...window.addeventlistener("load", function () { // add a callback to be run every time a document loads.
... // note that this includes frames/iframes within the document gbrowser.addeventlistener("load", examplepageload, true); }, false); ...
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What is JavaScript? - Learn web development
nsform: uppercase; text-align: center; border: 2px solid rgba(0,0,200,0.6); background: rgba(0,0,200,0.3); color: rgba(0,0,200,0.6); box-shadow: 1px 1px 2px rgba(0,0,200,0.4); border-radius: 10px; padding: 3px 10px; display: inline-block; cursor: pointer; } and finally, we can add some javascript to implement dynamic behaviour: const para = document.queryselector('p'); para.addeventlistener('click', updatename); function updatename() { let name = prompt('enter a new name'); para.textcontent = 'player 1: ' + name; } try clicking on this last version of the text label to see what happens (note also that you can find this demo on github — see the source code, or run it live)!
...for example, let's return to the block of javascript we saw in our first example: const para = document.queryselector('p'); para.addeventlistener('click', updatename); function updatename() { let name = prompt('enter a new name'); para.textcontent = 'player 1: ' + name; } here we are selecting a text paragraph (line 1), then attaching an event listener to it (line 3) so that when the paragraph is clicked, the updatename() code block (lines 5–8) is run.
... next, go to your text editor and add the following in your head — just before your closing </head> tag: <script> // javascript goes here </script> now we'll add some javascript inside our <script> element to make the page do something more interesting — add the following code just below the "// javascript goes here" line: document.addeventlistener("domcontentloaded", function() { function createparagraph() { let para = document.createelement('p'); para.textcontent = 'you clicked the button!'; document.body.appendchild(para); } const buttons = document.queryselectorall('button'); for(let i = 0; i < buttons.length ; i++) { buttons[i].addeventlistener('click', createparagraph); } }); save your file and refresh t...
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EventTarget.removeEventListener() - Web APIs
the eventtarget.removeeventlistener() method removes from the eventtarget an event listener previously registered with eventtarget.addeventlistener().
... return value undefined matching event listeners for removal given an event listener previously added by calling addeventlistener(), you may eventually come to a point at which you need to remove it.
... while addeventlistener() will let you add the same listener more than once for the same type if the options are different, the only option removeeventlistener() checks is the capture/usecapture flag.
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Using the Gamepad API - Web APIs
you can use gamepadconnected like this: window.addeventlistener("gamepadconnected", function(e) { console.log("gamepad connected at index %d: %s.
...gamepadconnected), a second event is dispatched to the focused window, gamepaddisconnected: window.addeventlistener("gamepaddisconnected", function(e) { console.log("gamepad disconnected from index %d: %s", e.gamepad.index, e.gamepad.id); }); the gamepad's index property will be unique per-device connected to the system, even if multiple controllers of the same type are used.
... var gamepads = {}; function gamepadhandler(event, connecting) { var gamepad = event.gamepad; // note: // gamepad === navigator.getgamepads()[gamepad.index] if (connecting) { gamepads[gamepad.index] = gamepad; } else { delete gamepads[gamepad.index]; } } window.addeventlistener("gamepadconnected", function(e) { gamepadhandler(e, true); }, false); window.addeventlistener("gamepaddisconnected", function(e) { gamepadhandler(e, false); }, false); this previous example also demonstrates how the gamepad property can be held after the event has completed — a technique we will use for device state querying later.
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Using Service Workers - Web APIs
let’s start this section by looking at a code sample — this is the first block you’ll find in our service worker: self.addeventlistener('install', (event) => { event.waituntil( caches.open('v1').then((cache) => { return cache.addall([ './sw-test/', './sw-test/index.html', './sw-test/style.css', './sw-test/app.js', './sw-test/image-list.js', './sw-test/star-wars-logo.jpg', './sw-test/gallery/', './sw-test/gallery/bountyhunters.jpg', './sw-test/gall...
... self.addeventlistener('fetch', (event) => { event.respondwith( // magic goes here ); }); we could start by simply responding with the resource whose url matches that of the network request, in each case: self.addeventlistener('fetch', (event) => { event.respondwith( caches.match(event.request) ); }); caches.match(event.request) allows us to match each resource requested from the network with the equ...
...we could do this: self.addeventlistener('fetch', (event) => { event.respondwith( caches.match(event.request).then((response) => { return response || fetch(event.request); }) ); }); if the resources aren't in the cache, they are requested from the network.
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Inputs and input sources - Web APIs
for example, if you need to keep up with which controller is held in each of the player's hands, you might do something like this: let inputsourcelist = null; let lefthandsource = null; let righthandsource = null; xrsession.addeventlistener("inputsourceschange", event => { inputsourcelist = event.session.inputsources; inputsourcelist.foreach(source => { switch(source) { case "left": lefthandsource = source; break; case "right": righthandsource = source; break; } }); }); the inputsourceschange event is also fired once when the session's creation callback first completes execu...
... xrsession.addeventlistener("select", event => { let inputsource = event.inputsource; let frame = event.frame; /* handle the event */ }); some actions may send these events very quickly, one after the other.
... picking up an object: handling squeezestart events xrsession.addeventlistener("squeezestart", event => { const targetrayspace = event.inputsource.targetrayspace; const hand = event.inputsource.handedness; let targetraypose = event.frame.getpose(targetrayspace, viewerrefspace); if (!targetraypose) { return; } let targetraytransform = targetraypose.transform; let targetobject = findtargetobject(targetraytransform); if (targetobject) { if (avatar.he...
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Border-radius generator - CSS: Cascading Style Sheets
-select: text; -ms-user-select: text; user-select: text; float: right; } javascript content 'use strict'; /** * ui-inputslidermanager */ var inputslidermanager = (function inputslidermanager() { var subscribers = {}; var sliders = []; var inputcomponent = function inputcomponent(obj) { var input = document.createelement('input'); input.setattribute('type', 'text'); input.addeventlistener('click', function(e) { this.select(); }); input.addeventlistener('change', function(e) { var value = parseint(e.target.value); if (isnan(value) === true) setvalue(obj.topic, obj.value); else setvalue(obj.topic, value); }); subscribe(obj.topic, function(value) { input.value = value + obj.unit; }); return input; } var slidercomponent = function slidercompon...
...ent(obj, sign) { var slider = document.createelement('div'); var startx = null; var start_value = 0; slider.addeventlistener("click", function(e) { setvalue(obj.topic, obj.value + obj.step * sign); }); slider.addeventlistener("mousedown", function(e) { startx = e.clientx; start_value = obj.value; document.body.style.cursor = "e-resize"; document.addeventlistener("mousemove", slidermotion); }); document.addeventlistener("mouseup", function(e) { document.removeeventlistener("mousemove", slidermotion); document.body.style.cursor = "auto"; slider.style.cursor = "pointer"; }); var slidermotion = function slidermotion(e) { slider.style.cursor = "e-resize"; var delta = (e.clientx - startx) / obj.sensivity | 0; var value = delta * obj.step + start_value; ...
...opic; checkbox.id = id; checkbox.setattribute('type', 'checkbox'); checkbox.checked = state; label.setattribute('for', id); if (name) { label.classname = 'text'; if (align) label.classname += ' ' + align; label.textcontent = name; } node.appendchild(checkbox); node.appendchild(label); this.node = node; this.topic = topic; this.checkbox = checkbox; checkbox.addeventlistener('change', function(e) { notify.call(this); }.bind(this)); buttons[topic] = this; } var getnode = function getnode(topic) { return buttons[topic].node; } var setvalue = function setvalue(topic, value) { try { buttons[topic].checkbox.checked = value; } catch(error) { console.log(error); } } var subscribe = function subscribe(topic, callback) { if (subscribers[top...
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On page load - Archive of obsolete content
lay firefox chrome://browser/content/browser.xul thunderbird chrome://messenger/content/messenger.xul navigator from seamonkey chrome://navigator/content/navigator.xul attaching a script attach a script to your overlay (see "attaching a script to an overlay") that adds a load event listener to appcontent element (browsers) or messagepane (mail): window.addeventlistener("load", function load(event){ window.removeeventlistener("load", load, false); //remove listener, no longer needed myextension.init(); },false); var myextension = { init: function() { var appcontent = document.getelementbyid("appcontent"); // browser if(appcontent){ appcontent.addeventlistener("domcontentloaded", myextension.onpageload, true); } var messagepane ...
...= document.getelementbyid("messagepane"); // mail if(messagepane){ messagepane.addeventlistener("load", function(event) { myextension.onpageload(event); }, true); } }, onpageload: function(aevent) { var doc = aevent.originaltarget; // doc is document that triggered "onload" event // do something with the loaded page.
... if(doc.location.href.search("forum") > -1) alert("a forum page is loaded"); // add event listener for page unload aevent.originaltarget.defaultview.addeventlistener("unload", function(event){ myextension.onpageunload(event); }, true); }, onpageunload: function(aevent) { // do something } }; current firefox trunk nightlies will fire the onpageload function for not only documents, but xul:images (favicons in tabbrowser).
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Advanced text formatting - Learn web development
width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); const output = document.queryselector('.output'); const code = textarea.value; const userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...w solution'; } updatecode(); }); const htmlsolution = '<dl>\n <dt>bacon</dt>\n <dd>the glue that binds the world together.</dd>\n <dt>eggs</dt>\n <dd>the glue that binds the cake together.</dd>\n <dt>coffee</dt>\n <dd>the drink that gets the world running in the morning.</dd>\n <dd>a light brown color.</dd>\n</dl>'; const solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { const scrollpos = textarea.scrolltop; const caretpos = textar...
...width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); const output = document.queryselector('.output'); const code = textarea.value; const userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
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Getting started with HTML - Learn web development
0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var solution = document.getelementbyid('solution'); var output = document.queryselector('.output'); var code = textarea.value; var userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...w solution'; } updatecode(); }); var htmlsolution = '<em>this is my text.</em>'; var solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { var scrollpos = textarea.scrolltop; var caretpos = textarea.selectionstart; var front = (textarea.value).substring(0, caretpos); var back = (textarea.value).substring(textarea.selectionend, textarea.value.length); textarea.value = front + text + back; caretpos = caretpos + text.length; te...
...: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var solution = document.getelementbyid('solution'); var output = document.queryselector('.output'); var code = textarea.value; var userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
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Making decisions in your code — conditionals - Learn web development
ather">select the weather type today: </label> <select id="weather"> <option value="">--make a choice--</option> <option value="sunny">sunny</option> <option value="rainy">rainy</option> <option value="snowing">snowing</option> <option value="overcast">overcast</option> </select> <p></p> const select = document.queryselector('select'); const para = document.queryselector('p'); select.addeventlistener('change', setweather); function setweather() { const choice = select.value; if (choice === 'sunny') { para.textcontent = 'it is nice and sunny outside today.
...ather">select the weather type today: </label> <select id="weather"> <option value="">--make a choice--</option> <option value="sunny">sunny</option> <option value="rainy">rainy</option> <option value="snowing">snowing</option> <option value="overcast">overcast</option> </select> <p></p> const select = document.queryselector('select'); const para = document.queryselector('p'); select.addeventlistener('change', setweather); function setweather() { const choice = select.value; switch (choice) { case 'sunny': para.textcontent = 'it is nice and sunny outside today.
...y-label { margin: 0; text-align: right; font-size: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); let code = textarea.value; let userentry = textarea.value; function updatecode() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = jssolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'show ...
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Useful string methods - Learn web development
y-label { margin: 0; text-align: right; font-size: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); let code = textarea.value; let userentry = textarea.value; function updatecode() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = jssolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'show ...
... \'get well soon\'];' + '\n' + '\nfor (let i = 0; i < greetings.length; i++) {' + '\n let input = greetings[i];' + '\n if (greetings[i].indexof(\'christmas\') !== -1) {' + '\n let result = input;' + '\n let listitem = document.createelement(\'li\');' + '\n listitem.textcontent = result;' + '\n list.appendchild(listitem);' + '\n }' + '\n}'; let solutionentry = jssolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { const scrollpos = textarea.scrol...
...y-label { margin: 0; text-align: right; font-size: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); let code = textarea.value; let userentry = textarea.value; function updatecode() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = jssolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'show ...
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What went wrong? Troubleshooting JavaScript - Learn web development
an error message to indicate what's gone wrong: "typeerror: guesssubmit.addeventlistener is not a function" a "learn more" link that links through to an mdn page that explains what this error means in greater detail.
... if we look at line 86 in our code editor, we'll find this line: guesssubmit.addeventlistener('click', checkguess); the error message says "guesssubmit.addeventlistener is not a function", which means that the function we're calling is not recognized by the javascript interpreter.
...here's a shortcut to save you some time in this instance: addeventlistener().
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Using files from web applications - Web APIs
you need to use eventtarget.addeventlistener() to add the change event listener, like this: const inputelement = document.getelementbyid("input"); inputelement.addeventlistener("change", handlefiles, false); function handlefiles() { const filelist = this.files; /* now you can work with the file list */ } getting information about selected file(s) the filelist object provided by the dom lists all of the files selected by the user, each ...
...b", "yib"]; for (nmultiple = 0, napprox = nbytes / 1024; napprox > 1; napprox /= 1024, nmultiple++) { soutput = napprox.tofixed(3) + " " + amultiples[nmultiple] + " (" + nbytes + " bytes)"; } // end of optional code document.getelementbyid("filenum").innerhtml = nfiles; document.getelementbyid("filesize").innerhtml = soutput; } document.getelementbyid("uploadinput").addeventlistener("change", updatesize, false); </script> </body> </html> using hidden file input elements using the click() method you can hide the admittedly ugly file <input> element and present your own interface for opening the file picker and displaying which file or files the user has selected.
... consider this html: <input type="file" id="fileelem" multiple accept="image/*" style="display:none"> <button id="fileselect">select some files</button> the code that handles the click event can look like this: const fileselect = document.getelementbyid("fileselect"), fileelem = document.getelementbyid("fileelem"); fileselect.addeventlistener("click", function (e) { if (fileelem) { fileelem.click(); } }, false); you can style the new button for opening the file picker as you wish.
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Advanced techniques: Creating and sequencing audio - Web APIs
" id="attack" type="range" min="0" max="1" value="0.2" step="0.1" /> <label for="release">release</label> <input name="release" id="release" type="range" min="0" max="1" value="0.5" step="0.1" /> now we can create some variables over in javascript and have them change when the input values are updated: let attacktime = 0.2; const attackcontrol = document.queryselector('#attack'); attackcontrol.addeventlistener('input', function() { attacktime = number(this.value); }, false); let releasetime = 0.5; const releasecontrol = document.queryselector('#release'); releasecontrol.addeventlistener('input', function() { releasetime = number(this.value); }, false); the final playsweep() function now we can expand our playsweep() function.
... let pulsehz = 880; const hzcontrol = document.queryselector('#hz'); hzcontrol.addeventlistener('input', function() { pulsehz = number(this.value); }, false); let lfohz = 30; const lfocontrol = document.queryselector('#lfo'); lfocontrol.addeventlistener('input', function() { lfohz = number(this.value); }, false); the final playpulse() function here's the entire playpulse() function: let pulsetime = 1; function playpulse() { let osc = audioctx.createoscillator(); osc.type...
...inputs and event handlers just like in previous sections: <label for="duration">duration</label> <input name="duration" id="duration" type="range" min="0" max="2" value="1" step="0.1" /> <label for="band">band</label> <input name="band" id="band" type="range" min="400" max="1200" value="1000" step="5" /> let noiseduration = 1; const durcontrol = document.queryselector('#duration'); durcontrol.addeventlistener('input', function() { noiseduration = number(this.value); }, false); let bandhz = 1000; const bandcontrol = document.queryselector('#band'); bandcontrol.addeventlistener('input', function() { bandhz = number(this.value); }, false); the final playnoise() function here's the entire playnoise() function: function playnoise() { const buffersize = audioctx.samplerate * noiseduration; /...
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Making PWAs work offline with Service workers - Progressive web apps (PWAs)
installation the api allows us to add event listeners for key events we are interested in — the first one is the install event: self.addeventlistener('install', (e) => { console.log('[service worker] install'); }); in the install listener, we can initialize the cache and add files to it for offline use.
... var gamesimages = []; for(var i=0; i<games.length; i++) { gamesimages.push('data/img/'+games[i].slug+'.jpg'); } var contenttocache = appshellfiles.concat(gamesimages); then we can manage the install event itself: self.addeventlistener('install', (e) => { console.log('[service worker] install'); e.waituntil( caches.open(cachename).then((cache) => { console.log('[service worker] caching all: app shell and content'); return cache.addall(contenttocache); }) ); }); there are two things that need an explanation here: what extendableevent.waituntil does, and what the caches object is.
...here is a simple usage example: self.addeventlistener('fetch', (e) => { console.log('[service worker] fetched resource '+e.request.url); }); the response can be anything we want: the requested file, its cached copy, or a piece of javascript code that will do something specific — the possibilities are endless.
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dev/panel - Archive of obsolete content
tooltip: "my new devtool's panel", icon: "./my-icon.png", url: "./my-panel.html", onready: function() { this.postmessage("message from the add-on"); } }); // export the constructor exports.mypanel = mypanel; // create a new tool, initialized // with the new constructor const mytool = new tool({ panels: { mypanel: mypanel } }); in the panel document script: // my-panel.js window.addeventlistener("message", function(event) { var content = document.getelementbyid("content"); content.textcontent = event.data; }); note that at the moment you have to pass an array of ports into postmessage, even if you don't need to use them: // main.js // require the sdk modules const { panel } = require("dev/panel"); const { tool } = require("dev/toolbox"); const { class } = require("sdk/core/herita...
...e panel document this.postmessage("message from the add-on", [panelside]); } }); // export the constructor exports.mypanel = mypanel; // create a new tool, initialized // with the new constructor const mytool = new tool({ panels: { mypanel: mypanel } }); in the panel document: retrieve the messageport from the event, and use it to send messages to the add-on // my-panel.js window.addeventlistener("message", function(event) { // retrieve the port var toaddon = event.ports[0]; toaddon.start(); toaddon.postmessage("message from the panel document"); console.log(toaddon); }); communicating with the debugger server the firefox developer tools use a client/server protocol: a tool, such as a javascript debugger or style editor, is the client, and the program being debugged, such as ...
...s.debuggee = null; }, onready: function() { this.debuggee.start(); this.postmessage("port", [this.debuggee]); } }); // export the constructor exports.mypanel = mypanel; // create a new tool, initialized // with the new constructor const mytool = new tool({ panels: { mypanel: mypanel } }); in my-panel.js: // my-panel.js var content = document.getelementbyid("content"); window.addeventlistener("message", function(event) { var debuggee = event.ports[0]; console.log(debuggee); debuggee.onmessage = function(event) { content.textcontent = json.stringify(event.data); } debuggee.postmessage({ "to":"root", "type":"listtabs" }); }); if you do this, don't forget to call start() on the port before passing it over to the panel document.
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Miscellaneous - Archive of obsolete content
</div> <script type="text/javascript"> var elm = document.getelementbyid("scrollarea"); elm.addeventlistener("dommousescroll", function scroll(event){ //event.detail is positive for a downward scroll, negative for an upward scroll alert("scrolling " + event.detail + " lines"); }, false); </script> if you do not receive a dommousescroll event while holding any of the modifier keys (ctrl,shift,alt,meta) you should check the mousewheel.withcontrolkey.action and related preferences.
... var focusedcontrol; window.addeventlistener("load", function(e) { onwindowload(e); }, false); function onwindowload() { gbrowser.addeventlistener("load", onpageload, true); } function onpageload() { pagedoc = document.commanddispatcher.focusedwindow.document; var inputlist = pagedoc.getelementsbytagname('input'); for (var i=1; i<inputlist.length; i++) { inputlist.item(i).
... addeventlistener("focus", function(e) {onfocusinput(e);}, false); inputlist.item(i).
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Migrate apps from Internet Explorer to Mozilla - Archive of obsolete content
you use the addeventlistener() and removeeventlistener() methods, and have the benefit of being able to set multiple listeners for the same event type.
...aevent : window.event; } function onpageload() { var element = document.getelementbyid("mydiv"); element.addeventlistener("click", handleevent, false); } </script> one advantage of addeventlistener() and removeeventlistener() over setting properties is that you can have multiple event listeners for the same event, each calling another function.
...instead, you should use the addeventlistener and removeeventlistener methods.
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XUL Event Propagation - Archive of obsolete content
in another example, an onload event handler for a xul window can register a box element to capture all the click events that are raised from its child elements: var bbox = document.getelementbyid("bigbox"); if (bbox) bbox.addeventlistener("click", function() { alert('captured'); }, true); ...
...any xul element may use the dom addeventlistener method to register itself to capture events.
... the syntax for this in xul is as follows: element = document.getelementbyid("id of the element"); element.addeventlistener(event name, event handler function, whether to register a capturing listener); the event handler code argument can be in-line code or a function.
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Client-side storage - Learn web development
add this snippet below your previous code: // stop the form from submitting when a button is pressed form.addeventlistener('submit', function(e) { e.preventdefault(); }); now we need to add an event listener, the handler function of which will run when the "say hello" button is clicked.
...add this to the bottom of your code: // run function when the 'say hello' button is clicked submitbtn.addeventlistener('click', function() { // store the entered name in web storage localstorage.setitem('name', nameinput.value); // run namedisplaycheck() to sort out displaying the // personalized greetings and updating the form display namedisplaycheck(); }); at this point we also need an event handler to run a function when the "forget" button is clicked — this is only displayed after the "say hello" b...
...add this to the bottom: // run function when the 'forget' button is clicked forgetbtn.addeventlistener('click', function() { // remove the stored name from web storage localstorage.removeitem('name'); // run namedisplaycheck() to sort out displaying the // generic greeting again and updating the form display namedisplaycheck(); }); it is now time to define the namedisplaycheck() function itself.
...And 2 more matches
Advanced animations - Web APIs
y: 2, radius: 25, color: 'blue', draw: function() { ctx.beginpath(); ctx.arc(this.x, this.y, this.radius, 0, math.pi * 2, true); ctx.closepath(); ctx.fillstyle = this.color; ctx.fill(); } }; function draw() { ctx.clearrect(0,0, canvas.width, canvas.height); ball.draw(); ball.x += ball.vx; ball.y += ball.vy; raf = window.requestanimationframe(draw); } canvas.addeventlistener('mouseover', function(e) { raf = window.requestanimationframe(draw); }); canvas.addeventlistener('mouseout', function(e) { window.cancelanimationframe(raf); }); ball.draw(); boundaries without any boundary collision testing our ball runs out of the canvas quickly.
...tx.fill(); } }; function draw() { ctx.clearrect(0,0, canvas.width, canvas.height); ball.draw(); ball.x += ball.vx; ball.y += ball.vy; if (ball.y + ball.vy > canvas.height || ball.y + ball.vy < 0) { ball.vy = -ball.vy; } if (ball.x + ball.vx > canvas.width || ball.x + ball.vx < 0) { ball.vx = -ball.vx; } raf = window.requestanimationframe(draw); } canvas.addeventlistener('mouseover', function(e) { raf = window.requestanimationframe(draw); }); canvas.addeventlistener('mouseout', function(e) { window.cancelanimationframe(raf); }); ball.draw(); acceleration to make the motion more real, you can play with the velocity like this, for example: ball.vy *= .99; ball.vy += .25; this slows down the vertical velocity each frame, so that the ball will just bounc...
... ctx.clearrect(0,0, canvas.width, canvas.height); ball.draw(); ball.x += ball.vx; ball.y += ball.vy; ball.vy *= .99; ball.vy += .25; if (ball.y + ball.vy > canvas.height || ball.y + ball.vy < 0) { ball.vy = -ball.vy; } if (ball.x + ball.vx > canvas.width || ball.x + ball.vx < 0) { ball.vx = -ball.vx; } raf = window.requestanimationframe(draw); } canvas.addeventlistener('mouseover', function(e) { raf = window.requestanimationframe(draw); }); canvas.addeventlistener('mouseout', function(e) { window.cancelanimationframe(raf); }); ball.draw(); trailing effect until now we have made use of the clearrect method when clearing prior frames.
...And 2 more matches
Video player styling basics - Developer guides
'unmute' : 'mute'); } } this function is then called by the relevant event handlers: video.addeventlistener('play', function() { changebuttonstate('playpause'); }, false); video.addeventlistener('pause', function() { changebuttonstate('playpause'); }, false); stop.addeventlistener('click', function(e) { video.pause(); video.currenttime = 0; progress.value = 0; // update the play/pause button's 'data-state' which allows the correct button image to be set via css changebuttonstate('p...
...laypause'); }); mute.addeventlistener('click', function(e) { video.muted = !video.muted; changebuttonstate('mute'); }); you might have noticed that there are new handlers where the play and pause events are reacted to on the video.
...to ensure this, a new click handler needs to be defined for the play/pause button so that it too raises the play and pause events: playpause.addeventlistener('click', function(e) { if (video.paused || video.ended) video.play(); else video.pause(); }); volume the altervolume() function, called when the player's volume buttons are clicked, also changes — it now calls a new function called checkvolume(): var checkvolume = function(dir) { if (dir) { var currentvolume = math.floor(video.volume * 10) / 10; if (dir === '+') { ...
...And 2 more matches
<input type="button"> - HTML: Hypertext Markup Language
WebHTMLElementinputbutton
a simple button we'll begin by creating a simple button with a click event handler that starts our machine (well, it toggles the value of the button and the text content of the following paragraph): <form> <input type="button" value="start machine"> </form> <p>the machine is stopped.</p> const button = document.queryselector('input'); const paragraph = document.queryselector('p'); button.addeventlistener('click', updatebutton); function updatebutton() { if (button.value === 'start machine') { button.value = 'stop machine'; paragraph.textcontent = 'the machine has started!'; } else { button.value = 'start machine'; paragraph.textcontent = 'the machine is stopped.'; } } the script gets a reference to the htmlinputelement object representing the <input> in the dom, saving thi...
...addeventlistener() is then used to establish a function that will be run when click events occur on the button.
... <form> <input type="button" value="start machine" accesskey="s"> </form> <p>the machine is stopped.</p> const button = document.queryselector('input'); const paragraph = document.queryselector('p'); button.addeventlistener('click', updatebutton); function updatebutton() { if (button.value === 'start machine') { button.value = 'stop machine'; paragraph.textcontent = 'the machine has started!'; } else { button.value = 'start machine'; paragraph.textcontent = 'the machine is stopped.'; } } note: the problem with the above example of course is that the user will not know what the access key ...
...And 2 more matches
remote/child - Archive of obsolete content
each frame then has a content property that's the top-level dom window for the frame, and addeventlistener/removeeventlistener functions that enable you to listen to dom events dispatched by the frame.
... addeventlistener adds an event listener for dom events dispatched to any existing and future frames.
... at this point you can't access frame's content yet, but you can add event listeners: const { frames } = require("sdk/remote/child"); frames.on("attach", function(frame) { console.log("new frame"); frame.addeventlistener("domcontentloaded", function(e) { console.log(e.target.location.href); }); }); detach triggered when a frame is removed (for example, the user closed a tab).
... methods addeventlistener(event, listener, iscapturing) adds an event listener for dom events dispatched by this content frame.
Forms related code snippets - Archive of obsolete content
ul", "aug", "sep", "oct", "nov", "dec"], sdays = ["m", "t", "w", "t", "f", "s", "s"], bzeroismonday = true, /* internal usage */ ainstances = [], amonthlengths = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31], rbgnnan = /^\d+/, rbgnandend = /^\d+|\d+\d+$/g, rmonth = /\-month\-/, rdecrease = /\-decr\-/; var /* customizable by user */ nzindex = 1000; window.addeventlistener ?
... addeventlistener("load", buildcalendars, false) : window.attachevent ?
... attachevent("onload", buildcalendars) : (onload = buildcalendars); document.addeventlistener ?
... document.addeventlistener("mousedown", ondocclick, false) : document.attachevent ?
Adding Events and Commands - Archive of obsolete content
window.addeventlistener( "load", function() { xulschoolchrome.browseroverlay.init(); }, false); you can do something similar with the onunload event, to do any cleanup you may need.
...also, note that the addeventlistener method receives the event name without the "on" prefix, while element attributes do have the prefix.
...the addeventlistener method allows you to control the phase where you want to handle an event, with the last argument of the function.
...document.addeventlistener( "xshellogreetingevent", function(aevent) { /* do stuff*/ }, false); be careful when doing this!
Appendix C: Avoiding using eval in Add-ons - Archive of obsolete content
passing around functions/code as strings often you'll want to pass functions or code to other functions, most notoriously settimeout and addeventlistener.
...settimeout("dosomething();", 100); addeventlistener("load", "myaddon.init(); myaddon.onload();", true); setinterval(am_i_a_string_or_function_reference_qmark, 100); that in itself is certainly not elegant, but it may also become a security issue if you pass code that was externally retrieved (or at least contains bits of externally retrieved data): // do not use!
... addeventlistener("load", function() { myaddon.init(); myaddon.onload(); }, true); function doxhr() { //...
... addeventlistener("load", myaddon.init.bind(myaddon), true); settimeout(alert.bind(null, xhr.responsetext), 100); function.bind() returns a new function.
Building accessible custom components in XUL - Archive of obsolete content
<code> var gfocuscell = null; function install_handlers() { var spreadsheet = window.document.getelementbyid('accjaxspreadsheet'); spreadsheet.addeventlistener('focus', spreadsheet_focus, true); spreadsheet.addeventlistener('click', spreadsheet_click, true); } function spreadsheet_focus(e) { if (e.target.tagname == 'grid') { if (!gfocuscell) { gfocuscell = e.target.getelementsbytagname('label')[0]; } gfocuscell.focus(); } else { gfocuscell = e.target; } } function spreadsheet_click(e) { e...
...<code> function install_handlers() { var spreadsheet = window.document.getelementbyid('accjaxspreadsheet'); spreadsheet.addeventlistener('keypress', spreadsheet_keypress, true); spreadsheet.addeventlistener('focus', spreadsheet_focus, true); spreadsheet.addeventlistener('click', spreadsheet_click, true); } </code> with this new event handler and associated helper functions, we can navigate between cells and headers using the arrow keys.
....org/keymaster/gatekeeper/there.is.only.xul"; const x2_ns ="http://www.w3.org/tr/xhtml2" function start_edit(label) { var value = label.value; settimeout(function(){ var textbox = document.createelementns(xul_ns, "textbox"); label.parentnode.replacechild(textbox, label); textbox.value = value; textbox.origvalue = value; textbox.flex = 1; textbox.focus(); textbox.select(); textbox.addeventlistener("blur", editable_cell_blur, true); textbox.addeventlistener("keypress", editable_cell_keypress, true); }, 0); } function done_edit(textbox, keepvalue) { var value = textbox.value; var label = document.createelementns(xul_ns, "label"); label.setattributens(x2_ns, "role", "wairole:gridcell"); textbox.parentnode.replacechild(label, textbox); if (keepvalue) { label.value = ...
...value; } else { label.value = textbox.origvalue; } label.flex = 1; label.addeventlistener("keypress", cell_keypress, true); return label; } function editable_cell_blur(e) { var textbox = e.target; settimeout(function() { done_edit(textbox, true); }, 0); } function editable_cell_keypress(e) { var textbox = e.target; switch (e.keycode) { case key_enter: settimeout(function() { var label = done_edit(textbox, true); label.focus(); }, 0); break; case key_escape: settimeout(function() { var label = done_edit(textbox, false); label.focus(); }, 0); break; } } </code> with this new code, we can now navigate to a specific cell within the spreadsheet and press enter to edit the value.
Adding Event Handlers - Archive of obsolete content
second, by calling an element's addeventlistener method.
... dom event listeners the second way to add an event handler is to call an element's addeventlistener method.
...the syntax is as follows: example 3 : source view <button id="okbutton" label="ok"/> <script> function buttonpressed(event){ alert('button was pressed!'); } var button = document.getelementbyid("okbutton"); button.addeventlistener('command', buttonpressed, true); </script> the getelementbyid() function returns the element with a given id, in this case the button.
... the addeventlistener() function is called to add a new capturing event listener.
Client-side form validation - Learn web development
th some simple html (feel free to put this in a blank html file; use a fresh copy of fruit-start.html as a basis, if you like): <form> <label for="mail">i would like you to provide me with an e-mail address:</label> <input type="email" id="mail" name="mail"> <button>submit</button> </form> and add the following javascript to the page: const email = document.getelementbyid("mail"); email.addeventlistener("input", function (event) { if (email.validity.typemismatch) { email.setcustomvalidity("i am expecting an e-mail address!"); } else { email.setcustomvalidity(""); } }); here we store a reference to the email input, then add an event listener to it that runs the contained code each time the value inside the input is changed.
...const form = document.getelementsbytagname('form')[0]; const email = document.getelementbyid('mail'); const emailerror = document.queryselector('#mail + span.error'); email.addeventlistener('input', function (event) { // each time the user types something, we check if the // form fields are valid.
... emailerror.innerhtml = ''; // reset the content of the message emailerror.classname = 'error'; // reset the visual state of the message } else { // if there is still an error, show the correct error showerror(); } }); form.addeventlistener('submit', function (event) { // if the email field is valid, we let the form submit if(!email.validity.valid) { // if it isn't, we display an appropriate error message showerror(); // then we prevent the form from being sent by canceling the event event.preventdefault(); } }); function showerror() { if(email.validity.valuemissing) { // if the field is empty // display the follo...
...// in modern browsers, you should prefer using element.nextelementsibling let error = email; while ((error = error.nextsibling).nodetype != 1); // as per the html5 specification const emailregexp = /^[a-za-z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-za-z0-9-]+(?:\.[a-za-z0-9-]+)*$/; // many legacy browsers do not support the addeventlistener method.
Images in HTML - Learn web development
: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var solution = document.getelementbyid('solution'); var output = document.queryselector('.output'); var code = textarea.value; var userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...w solution'; } updatecode(); }); var htmlsolution = '<img src="https://udn.realityripple.com/samples/ec/5a13bd14f6.jpg"\n alt="the head and torso of a dinosaur skeleton; it has a large head with long sharp teeth"\n width="200"\n height="171"\n title="a t-rex on display in the manchester university museum">'; var solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { var scrollpos = textarea.scrolltop; var caretpos = textarea.selectionst...
...: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var solution = document.getelementbyid('solution'); var output = document.queryselector('.output'); var code = textarea.value; var userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...w solution'; } updatecode(); }); var htmlsolution = '<figure>\n <img src="https://udn.realityripple.com/samples/ec/5a13bd14f6.jpg"\n alt="the head and torso of a dinosaur skeleton; it has a large head with long sharp teeth"\n width="200"\n height="171">\n <figcaption>a t-rex on display in the manchester university museum</figcaption>\n</figure>'; var solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { var scrollpos = textarea.scrolltop...
Video and Audio APIs - Learn web development
first of all, add the following to the bottom of your code, so that the playpausemedia() function is invoked when the play button is clicked: play.addeventlistener('click', playpausemedia); now to define playpausemedia() — add the following, again at the bottom of your code: function playpausemedia() { if(media.paused) { play.setattribute('data-icon','u'); media.play(); } else { play.setattribute('data-icon','p'); media.pause(); } } here we use an if statement to check whether the video is paused.
...add the following addeventlistener() lines below the previous one you added: stop.addeventlistener('click', stopmedia); media.addeventlistener('ended', stopmedia); the click event is obvious — we want to stop the video by running our stopmedia() function when the stop button is clicked.
... first of all, add the following two addeventlistener() lines below the previous ones: rwd.addeventlistener('click', mediabackward); fwd.addeventlistener('click', mediaforward); now on to the event handler functions — add the following code below your previous functions to define mediabackward() and mediaforward(): let intervalfwd; let intervalrwd; function mediabackward() { clearinterval(intervalfwd); fwd.classlist.remove('activ...
... add the following addeventlistener() line just below the others: media.addeventlistener('timeupdate', settime); now to define the settime() function.
A first splash into JavaScript - Learn web development
} else { lastresult.textcontent = 'wrong!'; lastresult.style.backgroundcolor = 'red'; if(userguess < randomnumber) { loworhi.textcontent = 'last guess was too low!' ; } else if(userguess > randomnumber) { loworhi.textcontent = 'last guess was too high!'; } } guesscount++; guessfield.value = ''; } guesssubmit.addeventlistener('click', checkguess); function setgameover() { guessfield.disabled = true; guesssubmit.disabled = true; resetbutton = document.createelement('button'); resetbutton.textcontent = 'start new game'; document.body.append(resetbutton); resetbutton.addeventlistener('click', resetgame); } function resetgame() { guesscount = 1; const resetpara...
... add the following line below your checkguess() function: guesssubmit.addeventlistener('click', checkguess); here we are adding an event listener to the guesssubmit button.
...note that we don't need to specify the parentheses when writing it inside addeventlistener().
...add this now, below the rest of your javascript: function setgameover() { guessfield.disabled = true; guesssubmit.disabled = true; resetbutton = document.createelement('button'); resetbutton.textcontent = 'start new game'; document.body.append(resetbutton); resetbutton.addeventlistener('click', resetgame); } the first two lines disable the form text input and button by setting their disabled properties to true.
Arrays - Learn web development
le-buttons"> <input id="reset" type="button" value="reset"> <input id="solution" type="button" value="show solution"> </div> const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); let code = textarea.value; let userentry = textarea.value; function updatecode() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = jssolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'show ...
...) {\n let subarray = products[i].split(\':\');\n let name = subarray[0];\n let price = number(subarray[1]);\n total += price;\n let itemtext = name + \' — $\' + price;\n\n let listitem = document.createelement(\'li\');\n listitem.textcontent = itemtext;\n list.appendchild(listitem);\n}\n\ntotalbox.textcontent = \'total: $\' + total.tofixed(2);'; let solutionentry = jssolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { const scrollpos = textarea.scro...
...y-label { margin: 0; text-align: right; font-size: 0.7rem; width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); let code = textarea.value; let userentry = textarea.value; function updatecode() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = jssolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'show ...
...earchinput.value);\n\n list.innerhtml = \'\';\n\n for(let i = 0; i < myhistory.length; i++) {\n itemtext = myhistory[i];\n const listitem = document.createelement(\'li\');\n listitem.textcontent = itemtext;\n list.appendchild(listitem);\n }\n\n if(myhistory.length >= 5) {\n myhistory.pop();\n }\n\n searchinput.value = \'\';\n searchinput.focus();\n }\n}'; let solutionentry = jssolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { const scrollpos = textarea.scrol...
Advanced Svelte: Reactivity, lifecycle, accessibility - Learn web development
we will also have to use addeventlistener() and removeeventlistener() to run specific tasks when the control receives focus.
...to get this function called whenever the node gets focused, we need an event listener along these lines: node.addeventlistener('focus', event => node.select()).
...add the following to the bottom of the todo.svelte <script> section: function selectonfocus(node) { if (node && typeof node.select === 'function' ) { // make sure node is defined and has a select() method const onfocus = event => node.select() // event handler node.addeventlistener('focus', onfocus) // when node gets focus call onfocus() return { destroy: () => node.removeeventlistener('focus', onfocus) // this will be executed when the node is removed from the dom } } } now we need to tell the <input> to use that function with the use:action directive: <input use:selectonfocus /> with this directive we are telling svelte ...
... give it the following content: export function selectonfocus(node) { if (node && typeof node.select === 'function' ) { // make sure node is defined and has a select() method const onfocus = event => node.select() // event handler node.addeventlistener('focus', onfocus) // when node gets focus call onfocus() return { destroy: () => node.removeeventlistener('focus', onfocus) // this will be executed when the node is removed from the dom } } } now import it from inside todo.svelte; add the following import statement just below the others: import { selectonfocus } from '../actions.js' and remo...
source-editor.jsm
method overview initialization and destruction void destroy(); void init(element aelement, object aconfig, function acallback); search operations number find(string astring, [optional] object options); number findnext(boolean awrap); number findprevious(boolean awrap); event management void addeventlistener(string aeventtype, function acallback); void removeeventlistener(string aeventtype, function acallback); undo stack operations boolean canredo(); boolean canundo(); void endcompoundchange(); boolean redo(); void resetundo(); void startcompoundchange(); boolean undo(); display management operations vo...
... addeventlistener() adds a new event listener to the editor.
... void addeventlistener( string aeventtype, function acallback ); parameters aeventtype the name of the event type to listen for; see event name constants for possible values.
... removeeventlistener() removes an event listener (previously established by calling addeventlistener() from the editor.
GlobalEventHandlers.onerror - Web APIs
error events are fired at various targets for different kinds of errors: when a javascript runtime error (including syntax errors and exceptions thrown within handlers) occurs, an error event using interface errorevent is fired at window and window.onerror() is invoked (as well as handlers attached by window.addeventlistener (not only capturing)).
...these error events do not bubble up to window, but (at least in firefox) can be handled with a window.addeventlistener configured with usecapture set to true.
... syntax for historical reasons, different arguments are passed to window.onerror and element.onerror handlers (as well as on error-type window.addeventlistener handlers).
... window.addeventlistener('error') window.addeventlistener('error', function(event) { ...
HTMLElement: animationcancel event - Web APIs
an event handler for this event can be added by setting the onanimationcancel property, or using addeventlistener().
... const animated = document.queryselector('.animated'); animated.addeventlistener('animationcancel', () => { console.log('animation canceled'); }); animated.style.display = 'none'; the same, but using the onanimationcancel property instead of addeventlistener(): const animated = document.queryselector('.animated'); animated.onanimationcancel = () => { console.log('animation canceled'); }; animated.style.display = 'none'; live example html <div class="animation-examp...
... } @keyframes slidein { from { transform: translatex(100%) scalex(3); } to { transform: translatex(0) scalex(1); } } js const animation = document.queryselector('p.animation'); const animationeventlog = document.queryselector('.animation-example>.event-log'); const applyanimation = document.queryselector('.animation-example>button.activate'); let iterationcount = 0; animation.addeventlistener('animationstart', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation started' `; }); animation.addeventlistener('animationiteration', () => { iterationcount++; animationeventlog.textcontent = `${animationeventlog.textcontent}'animation iterations: ${iterationcount}' `; }); animation.addeventlistener('animationend', () => { animationeventlog.textcontent =...
... `${animationeventlog.textcontent}'animation ended'`; animation.classlist.remove('active'); applyanimation.textcontent = "activate animation"; }); animation.addeventlistener('animationcancel', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation canceled'`; }); applyanimation.addeventlistener('click', () => { animation.classlist.toggle('active'); animationeventlog.textcontent = ''; iterationcount = 0; let active = animation.classlist.contains('active'); if (active) { applyanimation.textcontent = "cancel animation"; } else { applyanimation.textcontent = "activate animation"; } }); result specifications specification status comment css animations working draft initial definition ...
KeyboardEvent.key - Web APIs
WebAPIKeyboardEventkey
t-flex: 1; flex: 1; } #test-target { display: block; width: 100%; margin-bottom: 10px; } javascript let textarea = document.getelementbyid('test-target'), consolelog = document.getelementbyid('console-log'), btnclearconsole = document.getelementbyid('btn-clear-console'); function logmessage(message) { document.getelementbyid("console-log").innerhtml += message + "<br>"; } textarea.addeventlistener('keydown', (e) => { if (!e.repeat) logmessage(`key "${e.key}" pressed [event: keydown]`); else logmessage(`key "${e.key}" repeating [event: keydown]`); }); textarea.addeventlistener('beforeinput', (e) => { logmessage(`key "${e.data}" about to be input [event: beforeinput]`); }); textarea.addeventlistener('input', (e) => { logmessage(`key "${e.data}" input [event: input]`); }...
...); textarea.addeventlistener('keyup', (e) => { logmessage(`key "${e.key}" released [event: keyup]`); }); btnclearconsole.addeventlistener('click', (e) => { let child = consolelog.firstchild; while (child) { consolelog.removechild(child); child = consolelog.firstchild; } }); result note: on browsers that don't fully implement the inputevent interface which is used for the beforeinput and input events, you may get incorrect output on those lines of the log output.
... example this example uses eventtarget.addeventlistener() to listen for keydown events.
... window.addeventlistener("keydown", function (event) { if (event.defaultprevented) { return; // do nothing if the event was already processed } switch (event.key) { case "down": // ie/edge specific value case "arrowdown": // do something for "down arrow" key press.
Capabilities, constraints, and settings - Web APIs
we also need to set up an event listener to watch for the "start video" button to be clicked: document.getelementbyid("startbutton").addeventlistener("click", function() { startvideo(); }, false); applying constraint set updates next, we set up an event listener for the "apply constraints" button.
... document.getelementbyid("applybutton").addeventlistener("click", function() { if (!videotrack && !audiotrack) { startvideo(); } else { buildconstraints(); if (videotrack) { videotrack.applyconstraints(videoconstraints).then(function() { videosettingstext.value = json.stringify(videotrack.getsettings(), null, 2); }).catch(handleerror); } if (audiotrack) { audiotrack.applyconstraints(audioconstraints).t...
... document.getelementbyid("stopbutton").addeventlistener("click", function() { if (videotrack) { videotrack.stop(); } if (audiotrack) { audiotrack.stop(); } videotrack = audiotrack = null; videoelement.srcobject = null; }); this simply stops the active tracks, sets the videotrack and audiotrack variables to null so we know they're gone, and removes the stream from the <video> element by setting htmlmediaelement.srcobject to null.
...unction keydownhandler(event) { if (event.key == "tab") { let elem = event.target; let str = elem.value; let position = elem.selectionstart; let newstr = str.substring(0, position) + " " + str.substring(position, str.length); elem.value = newstr; elem.selectionstart = elem.selectionend = position + 2; event.preventdefault(); } } videoconstrainteditor.addeventlistener("keydown", keydownhandler, false); audioconstrainteditor.addeventlistener("keydown", keydownhandler, false); show constrainable properties the browser supports the last significant piece of the puzzle: code that displays, for the user's reference, a list of the constrainable properties which their browser supports.
Using the Notifications API - Web APIs
var n = new notification('my great song'); document.addeventlistener('visibilitychange', function() { if (document.visibilitystate === 'visible') { // the tab has become visible so clear the now-stale notification.
...because notification also inherits from eventtarget, it's possible to use the addeventlistener() method on it.
... tag example assume the following basic html: <button>notify me!</button> it's possible to handle multiple notifications this way: window.addeventlistener('load', function () { // at first, let's check if we have permission for notification // if not, let's ask for it if (window.notification && notification.permission !== "granted") { notification.requestpermission(function (status) { if (notification.permission !== status) { notification.permission = status; } }); } var button = document.getelementsbytagname(...
...'button')[0]; button.addeventlistener('click', function () { // if the user agreed to get notified // let's try to send ten notifications if (window.notification && notification.permission === "granted") { var i = 0; // using an interval cause some browsers (including firefox) are blocking notifications if there are too much in a certain time.
Page Visibility API - Web APIs
ined") { hidden = "webkithidden"; visibilitychange = "webkitvisibilitychange"; } var videoelement = document.getelementbyid("videoelement"); // if the page is hidden, pause the video; // if the page is shown, play the video function handlevisibilitychange() { if (document[hidden]) { videoelement.pause(); } else { videoelement.play(); } } // warn if the browser doesn't support addeventlistener or the page visibility api if (typeof document.addeventlistener === "undefined" || hidden === undefined) { console.log("this demo requires a browser, such as google chrome or firefox, that supports the page visibility api."); } else { // handle page visibility change document.addeventlistener(visibilitychange, handlevisibilitychange, false); // when the video pauses, set the title.
... // this shows the paused videoelement.addeventlistener("pause", function(){ document.title = 'paused'; }, false); // when the video plays, set the title.
... videoelement.addeventlistener("play", function(){ document.title = 'playing'; }, false); } properties added to the document interface the page visibility api adds the following properties to the document interface: document.hidden read only returns true if the page is in a state considered to be hidden to the user, and false otherwise.
... //startsimulation and pausesimulation defined elsewhere function handlevisibilitychange() { if (document.hidden) { pausesimulation(); } else { startsimulation(); } } document.addeventlistener("visibilitychange", handlevisibilitychange, false); specifications specification status comment page visibility (second edition) recommendation initial definition.
Pointer Lock API - Web APIs
if ("onpointerlockchange" in document) { document.addeventlistener('pointerlockchange', lockchangealert, false); } else if ("onmozpointerlockchange" in document) { document.addeventlistener('mozpointerlockchange', lockchangealert, false); } function lockchangealert() { if(document.pointerlockelement === canvas || document.mozpointerlockelement === canvas) { console.log('the pointer lock status is now locked'); // do something useful in response ...
... document.addeventlistener('pointerlockerror', lockerror, false); document.addeventlistener('mozpointerlockerror', lockerror, false); function lockerror(e) { alert("pointer lock failed"); } note: until firefox 50 the above events were prefixed with moz in firefox.
... // pointer lock event listener // hook pointer lock state change events for different browsers document.addeventlistener('pointerlockchange', lockchangealert, false); document.addeventlistener('mozpointerlockchange', lockchangealert, false); this function checks the pointlockelement property to see if it is our canvas.
... function lockchangealert() { if (document.pointerlockelement === canvas || document.mozpointerlockelement === canvas) { console.log('the pointer lock status is now locked'); document.addeventlistener("mousemove", updateposition, false); } else { console.log('the pointer lock status is now unlocked'); document.removeeventlistener("mousemove", updateposition, false); } } the updateposition() function updates the position of the ball on the canvas (x and y), and also includes if() statements to check whether the ball has gone off the edges of the canvas.
SubtleCrypto.exportKey() - Web APIs
*/ window.crypto.subtle.generatekey( { name: "aes-gcm", length: 256, }, true, ["encrypt", "decrypt"] ).then((key) => { const exportbutton = document.queryselector(".raw"); exportbutton.addeventlistener("click", () => { exportcryptokey(key); }); }); pkcs #8 export this example exports an rsa private signing key as a pkcs #8 object.
...*/ window.crypto.subtle.generatekey( { name: "rsa-pss", // consider using a 4096-bit key for systems that require long-term security moduluslength: 2048, publicexponent: new uint8array([1, 0, 1]), hash: "sha-256", }, true, ["sign", "verify"] ).then((keypair) => { const exportbutton = document.queryselector(".pkcs8"); exportbutton.addeventlistener("click", () => { exportcryptokey(keypair.privatekey); }); }); subjectpublickeyinfo export this example exports an rsa public encryption key as a pem-encoded subjectpublickeyinfo object.
...*/ window.crypto.subtle.generatekey( { name: "rsa-oaep", // consider using a 4096-bit key for systems that require long-term security moduluslength: 2048, publicexponent: new uint8array([1, 0, 1]), hash: "sha-256", }, true, ["encrypt", "decrypt"] ).then((keypair) => { const exportbutton = document.queryselector(".spki"); exportbutton.addeventlistener("click", () => { exportcryptokey(keypair.publickey); }); }); json web key import this code exports an ecdsa private signing key as a json web key object.
...*/ window.crypto.subtle.generatekey( { name: "ecdsa", namedcurve: "p-384" }, true, ["sign", "verify"] ).then((keypair) => { const exportbutton = document.queryselector(".jwk"); exportbutton.addeventlistener("click", () => { exportcryptokey(keypair.privatekey); }); }); specifications specification status comment web cryptography apithe definition of 'subtlecrypto.exportkey()' in that specification.
Using the Web Audio API - Web APIs
// select our play button const playbutton = document.queryselector('button'); playbutton.addeventlistener('click', function() { // check if context is in suspended state (autoplay policy) if (audiocontext.state === 'suspended') { audiocontext.resume(); } // play or pause track depending on state if (this.dataset.playing === 'false') { audioelement.play(); this.dataset.playing = 'true'; } else if (this.dataset.playing === 'true') { audioelement...
...our htmlmediaelement fires an ended event once it's finished playing, so we can listen for that and run code accordingly: audioelement.addeventlistener('ended', () => { playbutton.dataset.playing = 'false'; }, false); modifying sound let's delve into some basic modification nodes, to change the sound that we have.
... so let's grab this input's value and update the gain value when the input node has its value changed by the user: const volumecontrol = document.queryselector('#volume'); volumecontrol.addeventlistener('input', function() { gainnode.gain.value = this.value; }, false); note: the values of node objects (e.g.
...again let's use a range type input to vary this parameter: <input type="range" id="panner" min="-1" max="1" value="0" step="0.01"> we use the values from that input to adjust our panner values in the same way as we did before: const pannercontrol = document.queryselector('#panner'); pannercontrol.addeventlistener('input', function() { panner.pan.value = this.value; }, false); let's adjust our audio graph again, to connect all the nodes together: track.connect(gainnode).connect(panner).connect(audiocontext.destination); the only thing left to do is give the app a try: check out the final demo here on codepen.
Window.ondragdrop - Web APIs
WebAPIWindowondragdrop
syntax window.ondragdrop = funcref; window.addeventlistener("dragdrop", funcref, usecapturing); funcref the event handler function to be registered.
... the window.ondragdrop property and the ondragdrop attribute are not implemented in gecko (bug 112288), you have to use addeventlistener.
... see addeventlistener for details.
... <html> <head><title>dragdroptest</title> <script type="text/javascript"> window.addeventlistener("dragdrop", testfunc, false); function testfunc(event) { alert("dragdrop!"); event.stoppropagation(); } </script> </head> <body> i am bodytext </body> </html> specification not part of specification.
Using XMLHttpRequest - Web APIs
function reqlistener () { console.log(this.responsetext); } var oreq = new xmlhttprequest(); oreq.addeventlistener("load", reqlistener); oreq.open("get", "http://www.example.org/example.txt"); oreq.send(); types of requests a request made via xmlhttprequest can fetch the data in one of two ways, asynchronously or synchronously.
... load the transfer is complete; all data is now in the response var oreq = new xmlhttprequest(); oreq.addeventlistener("progress", updateprogress); oreq.addeventlistener("load", transfercomplete); oreq.addeventlistener("error", transferfailed); oreq.addeventlistener("abort", transfercanceled); oreq.open(); // ...
...the upload events are fired on the xmlhttprequest.upload object, as shown below: var oreq = new xmlhttprequest(); oreq.upload.addeventlistener("progress", updateprogress); oreq.upload.addeventlistener("load", transfercomplete); oreq.upload.addeventlistener("error", transferfailed); oreq.upload.addeventlistener("abort", transfercanceled); oreq.open(); note: progress events are not available for the file: protocol.
... one can also detect all three load-ending conditions (abort, load, or error) using the loadend event: req.addeventlistener("loadend", loadend); function loadend(e) { console.log("the transfer finished (although we don't know if it succeeded or not)."); } note there is no way to be certain, from the information received by the loadend event, as to which condition caused the operation to terminate; however, you can use this to handle tasks that need to be performed in all end-of-transfer scenarios.
Creating and triggering events - Developer guides
elem.addeventlistener('build', function (e) { /* ...
...elem.addeventlistener('build', function (e) { // e.target matches elem }, false); // target can be any element or other eventtarget.
...('form'); const textarea = document.queryselector('textarea'); // create a new event, allow bubbling, and provide any data you want to pass to the "detail" property const eventawesome = new customevent('awesome', { bubbles: true, detail: { text: () => textarea.value } }); // the form element listens for the custom "awesome" event and then consoles the output of the passed text() method form.addeventlistener('awesome', e => console.log(e.detail.text())); // as the user types, the textarea inside the form dispatches/triggers the event to fire, and uses itself as the starting point textarea.addeventlistener('input', e => e.target.dispatchevent(eventawesome)); creating and dispatching events dynamically elements can listen for events that haven't been created yet: <form> <textarea></textarea> </f...
...orm> const form = document.queryselector('form'); const textarea = document.queryselector('textarea'); form.addeventlistener('awesome', e => console.log(e.detail.text())); textarea.addeventlistener('input', function() { // create and dispatch/trigger an event on the fly // note: optionally, we've also leveraged the "function expression" (instead of the "arrow function expression") so "this" will represent the element this.dispatchevent(new customevent('awesome', { bubbles: true, detail: { text: () => textarea.value } })) }); triggering built-in events this example demonstrates simulating a click (that is programmatically generating a click event) on a checkbox using dom methods.
Communicating using "postMessage" - Archive of obsolete content
to simplify this most content modules provide an onmessage property as an argument to the constructor: panel = require("sdk/panel").panel({ onmessage: function(contentscriptmessage) { // handle message from the content script } }); message events versus user-defined events you can use message events as an alternative to user-defined events: var pagemodscript = "window.addeventlistener('mouseover', function(event) {" + " self.postmessage(event.target.tostring());" + "}, false);"; var pagemod = require('sdk/page-mod').pagemod({ include: ['*'], contentscript: pagemodscript, onattach: function(worker) { worker.on('message', function(message) { console.log('mouseover: ' + message); }); } }); the reason to prefer user...
...now we have to embed the event type in the message payload, and implement a switch function in the receiver to dispatch the message: var pagemodscript = "window.addeventlistener('mouseover', function(event) {" + " self.postmessage({" + " kind: 'mouseover'," + " element: event.target.tostring()" + " });" + "}, false);" + "window.addeventlistener('mouseout', function(event) {" + " self.postmessage({" + " kind: 'mouseou...
...r) { worker.on('message', function(message) { switch(message.kind) { case 'mouseover': console.log('mouseover: ' + message.element); break; case 'mouseout': console.log('mouseout: ' + message.element); break; } }); } }); implementing the same add-on with user-defined events is shorter and more readable: var pagemodscript = "window.addeventlistener('mouseover', function(event) {" + " self.port.emit('mouseover', event.target.tostring());" + "}, false);" + "window.addeventlistener('mouseout', function(event) {" + " self.port.emit('mouseout', event.target.tostring());" + "}, false);"; var pagemod = require('sdk/page-mod').pagemod({ include:...
Content Scripts - Archive of obsolete content
.pagemod({ include: "*", contentscript: myscript, contentscriptwhen: "start" }); this will work fine on most pages, but will fail on pages which also assign to onclick: <html> <head> </head> <body> <script> window.onclick = function() { window.alert("it's my click now!"); } </script> </body> </html> for these reasons, it's better to add event listeners using addeventlistener(), defining the listener as a function: var themessage = "hello from content script!"; anelement.onclick = function() { alert(themessage); }; anotherelement.addeventlistener("click", function() { alert(themessage); }); communicating with the add-on to enable add-on scripts and content scripts to communicate with each other, each end of the conversation has access to a port object.
...// main.js var pagemods = require("sdk/page-mod"); var self = require("sdk/self"); var pagemod = pagemods.pagemod({ include: ['*'], contentscriptfile: self.data.url("content-script.js"), onattach: startlistening }); function startlistening(worker) { worker.port.on('click', function(html) { worker.port.emit('warning', 'do not click this again'); }); } // content-script.js window.addeventlistener('click', function(event) { self.port.emit('click', event.target.tostring()); event.stoppropagation(); event.preventdefault(); }, false); self.port.on('warning', function(message) { window.alert(message); }); in the add-on above there are two messages: click is sent from the page-mod to the add-on, when the user clicks an element in the page warning sends a silly string back to the ...
... var pagemod = require("sdk/page-mod"); pagemod.pagemod({ include: "*.mozilla.org", contentscript: 'function contextmenualert(href) {' + ' window.alert("the context menu was clicked on url:\\n" + href);' + '};' + 'window.addeventlistener("myaddonid-contextmenu-clicked",' + ' function(event){contextmenualert(event.detail);});' }); let cm = require("sdk/context-menu"); cm.item({ label: "alert url", context: [ cm.urlcontext(["*.mozilla.org"]), cm.selectorcontext("a[href]") ], contentscript: 'self.on("click", function (node, data) {' + ' var event = new customeven...
panel - Archive of obsolete content
var myscript = "window.addeventlistener('click', function(event) {" + " var t = event.target;" + " if (t.nodename == 'a')" + " self.port.emit('click-link', t.tostring());" + "}, false);" var mypanel = require("sdk/panel").panel({ contenturl: "http://www.bbc.co.uk/mobile/index.html", contentscript: myscript }); mypanel.port.on("click-link", function(url) { console.
...var textarea = document.getelementbyid("edit-box"); textarea.addeventlistener('keyup', function onkeyup(event) { if (event.keycode == 13) { // remove the newline.
...var textarea = document.getelementbyid("edit-box"); textarea.addeventlistener('keyup', function onkeyup(event) { if (event.keycode == 13) { // remove the newline.
Introducing the Audio API extension - Archive of obsolete content
id="audio-element" src="song.ogg" controls="true" style="width: 512px;"> </audio> <script> function loadedmetadata() { channels = audio.mozchannels; rate = audio.mozsamplerate; framebufferlength = audio.mozframebufferlength; } var audio = document.getelementbyid('audio-element'); audio.addeventlistener('loadedmetadata', loadedmetadata, false); </script> </body> </html> the mozaudioavailable event as the audio is played, sample data is made available to the audio layer and the audio buffer (size defined in mozframebufferlength) gets filled with those samples.
...fferlength; } function audioavailable(event) { var framebuffer = event.framebuffer; var t = event.time; var text = "samples at: " + t + "\n"; text += framebuffer[0] + " " + framebuffer[1]; raw.innerhtml = text; } var raw = document.getelementbyid('raw'); var audio = document.getelementbyid('audio-element'); audio.addeventlistener('mozaudioavailable', audioavailable, false); audio.addeventlistener('loadedmetadata', loadedmetadata, false); </script> </body> </html> creating an audio stream it is also possible to create and setup an <audio> element for raw writing from script (i.e., without a src attribute).
... a2.mozsetup(a1.mozchannels, a1.mozsamplerate); } function audioavailable(event) { // write the current framebuffer var framebuffer = event.framebuffer; writeaudio(framebuffer); } a1.addeventlistener('mozaudioavailable', audioavailable, false); a1.addeventlistener('loadedmetadata', loadedmetadata, false); function writeaudio(audio) { buffers.push(audio); // if there's buffered data, write that while(buffers.length > 0) { var buffer = buffers.shift(); var written = a2.mozwriteaudio(buffer); // // if all data wasn't written, keep it in the buffers: if(written < buffer.le...
Focus and Selection - Archive of obsolete content
you can also add event handlers dynamically using the dom function addeventlistener.
...example 3 : source view <window id="focus-example" title="focus example" onload="init();" xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"> <script> function init(){ addeventlistener("focus",setfocusedelement,true); } function setfocusedelement(){ var focused = document.commanddispatcher.focusedelement; document.getelementbyid("focused").value = focused.tagname; } </script> <hbox> <label control="username" value="user name:"/> <textbox id="username"/> </hbox> <button label="hello"/> <checkbox label="remember this decision"/> <label id="focused" value="-no focus-"/...
...we want to use a capturing event handler, so the addeventlistener method needs to be used.
Common causes of memory leaks in extensions - Extensions
consider the following example code that could be part of your browser.xul overlay: gbrowser.addeventlistener("domcontentloaded", function(evt) { var contentdoc = evt.originaltarget; var i = 0; // refresh the title once each second setinterval(function() { contentdoc.title = ++i; }, 1000); }, false); one would normally expect that the interval (or timer) would be destroyed as soon as the document unloads, in the same way that event listeners are automatically destroyed.
... window.addeventlistener("leaky", leakref, true); // the following line still fails to avoid the leak, as usecapture differs // and removeeventlistener will not remove anything.
... in overlay code you may use an unload event listener: addeventlistener("unload", function() { services.obs.removeobserver(myobserver, "private-browsing"); }, false); in bootstrap.js (restartless add-ons) unregister your observer in your shutdown function: function shutdown() { // ...
Unconventional controls - Game development
you can check them by printing the responses out in the console: window.addeventlistener("keydown", function(event) { console.log(event.keycode); }, this); every key pressed on the remote will show its key code in the console.
...all that is needed is checking for key presses: window.addeventlistener("keydown", function(event) { switch(event.keycode) { case 8: { // pause the game break; } case 588: { // detonate bomb break; } // ...
... an event listener for device proximity would look like this: window.addeventlistener('deviceproximity', function(event) { var min = event.min; var max = event.max; var proximity = event.value; }); the min and max values are the minimum and the maximum distances respectively between which the sensor can detect the exact proximity value.
Example 4 - Learn web development
ector('.value'); var optionlist = select.queryselectorall('.option'); nativewidget.selectedindex = index; value.innerhtml = optionlist[index].innerhtml; highlightoption(select, optionlist[index]); }; function getindex(select) { var nativewidget = select.previouselementsibling; return nativewidget.selectedindex; }; // ------------- // // event binding // // ------------- // window.addeventlistener("load", function () { var form = document.queryselector('form'); form.classlist.remove("no-widget"); form.classlist.add("widget"); }); window.addeventlistener('load', function () { var selectlist = document.queryselectorall('.select'); selectlist.foreach(function (select) { var optionlist = select.queryselectorall('.option'); optionlist.foreach(function (option) { opti...
...on.addeventlistener('mouseover', function () { highlightoption(select, option); }); }); select.addeventlistener('click', function (event) { toggleoptlist(select); }); select.addeventlistener('focus', function (event) { activeselect(select, selectlist); }); select.addeventlistener('blur', function (event) { deactivateselect(select); }); }); }); window.addeventlistener('load', function () { var selectlist = document.queryselectorall('.select'); selectlist.foreach(function (select) { var optionlist = select.queryselectorall('.option'), selectedindex = getindex(select); select.tabindex = 0; select.previouselementsibling.tabindex = -1; updatevalue(select, selectedindex); optionlist.foreach(function (option, in...
...dex) { option.addeventlistener('click', function (event) { updatevalue(select, index); }); }); select.addeventlistener('keyup', function (event) { var length = optionlist.length, index = getindex(select); if (event.keycode === 27) { deactivateselect(select); } if (event.keycode === 40 && index < length - 1) { index++; } if (event.keycode === 38 && index > 0) { index--; } updatevalue(select, index); }); }); }); result ...
Introducing asynchronous JavaScript - Learn web development
let's look at a simple example (see it live here, and see the source): const btn = document.queryselector('button'); btn.addeventlistener('click', () => { alert('you clicked me!'); let pelem = document.createelement('p'); pelem.textcontent = 'this is a newly-added paragraph.'; document.body.appendchild(pelem); }); in this block, the lines are executed one after the other: we grab a reference to a <button> element that is already available in the dom.
... an example of an async callback is the second parameter of the addeventlistener() method (as we saw in action above): btn.addeventlistener('click', () => { alert('you clicked me!'); let pelem = document.createelement('p'); pelem.textcontent = 'this is a newly-added paragraph.'; document.body.appendchild(pelem); }); the first parameter is the type of event to be listened for, and the second parameter is a callback function that is invoked when the event is fired.
... it worked :) if this confuses you, then consider the following smaller example: console.log("registering click handler"); button.addeventlistener('click', () => { console.log("get click"); }); console.log("all done"); this is very similar in behavior — the first and third console.log() messages will be shown immediately, but the second one is blocked from running until someone clicks the mouse button.
Introduction to web APIs - Learn web development
st playbtn = document.queryselector('button'); const volumeslider = document.queryselector('.volume'); const audiosource = audioctx.createmediaelementsource(audioelement); next up we include a couple of event handlers that serve to toggle between play and pause when the button is pressed and reset the display back to the beginning when the song has finished playing: // play/pause audio playbtn.addeventlistener('click', function() { // check if context is in suspended state (autoplay policy) if (audioctx.state === 'suspended') { audioctx.resume(); } // if track is stopped, play it if (this.getattribute('class') === 'paused') { audioelement.play(); this.setattribute('class', 'playing'); this.textcontent = 'pause' // if track is playing, stop it } els...
...e if (this.getattribute('class') === 'playing') { audioelement.pause(); this.setattribute('class', 'paused'); this.textcontent = 'play'; } }); // if track ends audioelement.addeventlistener('ended', function() { playbtn.setattribute('class', 'paused'); playbtn.textcontent = 'play'; }); note: some of you may notice that the play() and pause() methods being used to play and pause the track are not part of the web audio api; they are part of the htmlmediaelement api, which is different but closely-related.
... next, we create a gainnode object using the audiocontext.creategain() method, which can be used to adjust the volume of audio fed through it, and create another event handler that changes the value of the audio graph's gain (volume) whenever the slider value is changed: const gainnode = audioctx.creategain(); volumeslider.addeventlistener('input', function() { gainnode.gain.value = this.value; }); the final thing to do to get this to work is to connect the different nodes in the audio graph up, which is done using the audionode.connect() method available on every node type: audiosource.connect(gainnode).connect(audioctx.destination); the audio starts in the source, which is then connected to the gain node so the audio's volume can be adjusted.
Creating JavaScript callbacks in components
javascript functions as callbacks another common use of the pattern is found in addeventlistener / removeeventlistener.
... a nice feature of addeventlistener is that you can pass a javascript function in place of the callback listener interface.
... remember (or discover) that addeventlistener is a method of the nsidomeventtarget interface and is defined as such: void addeventlistener(in domstring type, in nsidomeventlistener listener, in boolean usecapture); however, it is extremely common to see developers pass a normal javascript function for the listener instead of an nsidomeventlistener implementation: function doload(event) { // do something here } window.addeventlistener("load", doload, false); revealing the magic how is this possible?
Cross Process Object Wrappers
for example, this frame script sends a dom node to chrome when the user clicks it, as the clicked property of the third argument: // frame script addeventlistener("click", function (event) { sendasyncmessage("my-e10s-extension-message", {}, { clicked : event.target }); }, false); in the chrome script, the dom node is now accessible through a cross process object wrapper, as a property of the objects property of the message.
...*/ var button = content.document.getelementbyid("click-me"); button.addeventlistener("mouseover", function (event) { sendasyncmessage("my-addon-message", {}, { element : event.target }); }, false); // chrome script /* load the frame script, then listen for the message.
...*/ browsermm.loadframescript("chrome://my-addon/content/frame-script.js", false); browsermm.addmessagelistener("my-addon-message", function(message) { let wrapper = message.objects.element; wrapper.addeventlistener("click", function() { console.log("they clicked"); }); }); mapping content documents to xul browsers a common pattern is to get the xul <browser> that corresponds to a content document.
Components.utils.cloneInto
example this add-on script creates an object, clones it into the content window and makes it a property of the content window global: // add-on script var addonscriptobject = {"greeting" : "hello from add-on"}; contentwindow.addonscriptobject = cloneinto(addonscriptobject, contentwindow); scripts running in the page can now access the object: // page script button.addeventlistener("click", function() { console.log(window.addonscriptobject.greeting); // "hello from add-on" }, false); of course, you don't have to assign the clone to the window itself: you can assign it to some other object in the target scope: contentwindow.foo.addonscriptobject = cloneinto(addonscriptobject, contentwindow); you can also pass it into a function defined in the page script.
...in components.utils.exportfunction: // add-on script var addonscriptobject = { greetme: function() { alert("hello from add-on"); } }; contentwindow.addonscriptobject = cloneinto(addonscriptobject, contentwindow, {clonefunctions: true}); // page script var test = document.getelementbyid("test"); test.addeventlistener("click", function() { window.addonscriptobject.greetme(); }, false); cloning objects that contain dom elements by default, if the object you clone contains objects that are reflected from c++, such as dom elements, the cloning operation will fail with an error.
...en the object you clone is allowed to contain these objects: // add-on script var addonscriptobject = { body: contentwindow.document.body }; contentwindow.addonscriptobject = cloneinto(addonscriptobject, contentwindow, {wrapreflectors: true}); // page script var test = document.getelementbyid("test"); test.addeventlistener("click", function() { console.log(window.addonscriptobject.body.innerhtml); }, false); access to these objects in the target scope is subject to the normal security checks.
Components.utils.exportFunction
made in the exported function will affect the original object that was passed in: // privileged scope: for example, a content script function changemyname(user) { user.name = "bill"; } exportfunction(changemyname, contentwindow, { defineas: "changemyname" }); // less-privileged scope: for example, a page script var user = {name: "jim"}; var test = document.getelementbyid("test"); test.addeventlistener("click", function() { console.log(user.name); // "jim" window.changemyname(user); console.log(user.name); // "bill" }, false); note that this is subject to the normal rules of xrays: for example, an expando property added to a dom node will not be visible in the original object.
...: for example, a content script function loguser(user) { // console.log(user.getuser()); // error console.log(user.wrappedjsobject.getuser()); // "bill" } exportfunction(loguser, contentwindow, { defineas: "loguser" }); // less-privileged scope: for example, a page script var user = {getuser: function() {return "bill";}} var test = document.getelementbyid("test"); test.addeventlistener("click", function() { window.loguser(user); }, false); passing functions as arguments if functions are given as arguments, these are also passed as xrays.
...d function just works, making the allowcallbacks option redundant: // privileged scope: for example, a content script function loguser(getuser) { console.log(getuser()); // "bill" } exportfunction(loguser, unsafewindow, { defineas: "loguser" }); // less-privileged scope: for example, a page script function getuser() { return "bill"; } var test = document.getelementbyid("test"); test.addeventlistener("click", function() { window.loguser(getuser); }, false); cross-origin checking when the exported function is called each argument, including this, is checked to make sure that the caller subsumes that argument.
nsIXMLHttpRequest
try something like this: nscomptr<nsidomeventtarget> target(do_queryinterface(myxmlhttpreq)); target->addeventlistener(ns_literal_string("load"), mylistener, pr_false) where mylistener is your event listener object that implements the interface nsidomeventlistener.
... though actually, if you use addeventlistener from c++ weird things will happen too, since the result will depend on what js happens to be on the stack when you do it....
... if (xhr.status == 200) { cb(xhr.response); break; } default: services.prompt.alert(null, 'xhr error', 'error fetching package: ' + xhr.statustext + ' [' + ev.type + ':' + xhr.status + ']'); break; } }; let evf = f => ['load', 'error', 'abort'].foreach(f); evf(m => xhr.addeventlistener(m, handler, false)); xhr.mozbackgroundrequest = true; xhr.open('get', url, true); xhr.channel.loadflags |= ci.nsirequest.load_anonymous | ci.nsirequest.load_bypass_cache | ci.nsirequest.inhibit_persistent_caching; xhr.responsetype = "arraybuffer"; //dont set it, so it returns string, you dont want arraybuffer.
Pixel manipulation with canvas - Web APIs
img.style.display = 'none'; }; var color = document.getelementbyid('color'); function pick(event) { var x = event.layerx; var y = event.layery; var pixel = ctx.getimagedata(x, y, 1, 1); var data = pixel.data; var rgba = 'rgba(' + data[0] + ', ' + data[1] + ', ' + data[2] + ', ' + (data[3] / 255) + ')'; color.style.background = rgba; color.textcontent = rgba; } canvas.addeventlistener('mousemove', pick); painting pixel data into a context you can use the putimagedata() method to paint pixel data into a context: ctx.putimagedata(myimagedata, dx, dy); the dx and dy parameters indicate the device coordinates within the context at which to paint the top left corner of the pixel data you wish to draw.
... ctx.putimagedata(imagedata, 0, 0); }; var grayscale = function() { for (var i = 0; i < data.length; i += 4) { var avg = (data[i] + data[i + 1] + data[i + 2]) / 3; data[i] = avg; // red data[i + 1] = avg; // green data[i + 2] = avg; // blue } ctx.putimagedata(imagedata, 0, 0); }; var invertbtn = document.getelementbyid('invertbtn'); invertbtn.addeventlistener('click', invert); var grayscalebtn = document.getelementbyid('grayscalebtn'); grayscalebtn.addeventlistener('click', grayscale); } zooming and anti-aliasing with the help of the drawimage() method, a second canvas and the imagesmoothingenabled property, we are able to zoom into our picture and see the details.
...none'; var zoomctx = document.getelementbyid('zoom').getcontext('2d'); var smoothbtn = document.getelementbyid('smoothbtn'); var togglesmoothing = function(event) { zoomctx.imagesmoothingenabled = this.checked; zoomctx.mozimagesmoothingenabled = this.checked; zoomctx.webkitimagesmoothingenabled = this.checked; zoomctx.msimagesmoothingenabled = this.checked; }; smoothbtn.addeventlistener('change', togglesmoothing); var zoom = function(event) { var x = event.layerx; var y = event.layery; zoomctx.drawimage(canvas, math.min(math.max(0, x - 5), img.width - 10), math.min(math.max(0, y - 5), img.height - 10), 10, 10, 0, 0, 200, 200); }; canvas.addeventlisten...
Detecting device orientation - Web APIs
window.addeventlistener("deviceorientation", handleorientation, true); after registering your event listener (in this case, a javascript function called handleorientation()), your listener function periodically gets called with updated orientation data.
...nstrain the x value to the range [-90,90] if (x > 90) { x = 90}; if (x < -90) { x = -90}; // to make computation easier we shift the range of // x and y to [0,180] x += 90; y += 90; // 10 is half the size of the ball // it center the positioning point to the center of the ball ball.style.top = (maxy*y/180 - 10) + "px"; ball.style.left = (maxx*x/180 - 10) + "px"; } window.addeventlistener('deviceorientation', handleorientation); click here to open this example in a new window; because deviceorientation doesn't work in a cross-origin <iframe> in all browsers.
... processing motion events motion events are handled the same way as the orientation events except that they have their own event's name: devicemotion window.addeventlistener("devicemotion", handlemotion, true); what's really changed are the information provided within the devicemotionevent object passed as a parameter of the handlemotion function.
Document: DOMContentLoaded event - Web APIs
examples basic usage document.addeventlistener('domcontentloaded', (event) => { console.log('dom fully loaded and parsed'); }); delaying domcontentloaded <script> document.addeventlistener('domcontentloaded', (event) => { console.log('dom fully loaded and parsed'); }); for( let i = 0; i < 1000000000; i++) {} // this synchronous script is going to delay parsing of the dom, // so the domcontentloaded event is going to launch ...
... function dosomething() { console.info('dom loaded'); } if (document.readystate === 'loading') { // loading hasn't finished yet document.addeventlistener('domcontentloaded', dosomething); } else { // `domcontentloaded` has already fired dosomething(); } live example html <div class="controls"> <button id="reload" type="button">reload</button> </div> <div class="event-log"> <label>event log:</label> <textarea readonly class="event-log-contents" rows="8" cols="30"></textarea> </div> css body { display: grid; grid-template-areas: "control log"; } .controls { grid-area: control; display: flex; alig...
...n-items: center; justify-content: center; } .event-log { grid-area: log; } .event-log-contents { resize: none; } label, button { display: block; } #reload { height: 2rem; } js const log = document.queryselector('.event-log-contents'); const reload = document.queryselector('#reload'); reload.addeventlistener('click', () => { log.textcontent =''; window.settimeout(() => { window.location.reload(true); }, 200); }); window.addeventlistener('load', (event) => { log.textcontent = log.textcontent + 'load\n'; }); document.addeventlistener('readystatechange', (event) => { log.textcontent = log.textcontent + `readystate: ${document.readystate}\n`; }); document.addeventlistener('domcontentloaded', (event) => { log.textcontent = log.textcontent + `domcontentloaded\n`; })...
Document: drag event - Web APIs
ggable </div> </div> <div class="dropzone"></div> <div class="dropzone"></div> <div class="dropzone"></div> css #draggable { width: 200px; height: 20px; text-align: center; background: white; } .dropzone { width: 200px; height: 20px; background: blueviolet; margin-bottom: 10px; padding: 10px; } javascript var dragged; /* events fired on the draggable target */ document.addeventlistener("drag", function(event) { }, false); document.addeventlistener("dragstart", function(event) { // store a ref.
... on the dragged elem dragged = event.target; // make it half transparent event.target.style.opacity = .5; }, false); document.addeventlistener("dragend", function(event) { // reset the transparency event.target.style.opacity = ""; }, false); /* events fired on the drop targets */ document.addeventlistener("dragover", function(event) { // prevent default to allow drop event.preventdefault(); }, false); document.addeventlistener("dragenter", function(event) { // highlight potential drop target when the draggable element enters it if (event.target.classname == "dropzone") { event.target.style.background = "purple"; } }, false); document.addeventlistener("dragleave", function(event) { // reset background of potential drop target when the draggable element leaves it if (event.t...
...arget.classname == "dropzone") { event.target.style.background = ""; } }, false); document.addeventlistener("drop", function(event) { // prevent default action (open as link for some elements) event.preventdefault(); // move dragged elem to the selected drop target if (event.target.classname == "dropzone") { event.target.style.background = ""; dragged.parentnode.removechild( dragged ); event.target.appendchild( dragged ); } }, false); specifications specification status comment html living standardthe definition of 'drag event' in that specification.
Document: keyup event - Web APIs
to ignore all keyup events that are part of composition, do something like this (229 is a special value set for a keycode relating to an event that has been processed by an ime): eventtarget.addeventlistener("keyup", event => { if (event.iscomposing || event.keycode === 229) { return; } // do something }); examples this example logs the keyboardevent.code value whenever you release a key.
... addeventlistener keyup example <p>focus the iframe first (e.g.
... by clicking in it), then try pressing some keys.</p> <p id="log"></p> const log = document.getelementbyid('log'); document.addeventlistener('keyup', logkey); function logkey(e) { log.textcontent += ` ${e.code}`; } onkeyup equivalent document.onkeyup = logkey; specifications specification status ui events working draft ...
Using FormData Objects - Web APIs
d size="32" maxlength="64" /><br /> <label>custom file label:</label> <input type="text" name="filelabel" size="12" maxlength="32" /><br /> <label>file to stash:</label> <input type="file" name="file" required /> <input type="submit" value="stash the file!" /> </form> <div></div> then you can send it using code like the following: var form = document.forms.nameditem("fileinfo"); form.addeventlistener('submit', function(ev) { var ooutput = document.queryselector("div"), odata = new formdata(form); odata.append("customfield", "this is some extra data"); var oreq = new xmlhttprequest(); oreq.open("post", "stash.php", true); oreq.onload = function(oevent) { if (oreq.status == 200) { ooutput.innerhtml = "uploaded!"; } else { ooutput.innerhtml = "error " + ore...
... typically this is used as shown in our simple formdata event demo — in the javascript we reference a form: const formelem = document.queryselector('form'); in our submit event handler we use preventdefault to stop the default form submission, then invoke a formdata constructor to trigger the formdata event: formelem.addeventlistener('submit', (e) => { // on form submission, prevent default e.preventdefault(); // construct a formdata object, which fires the formdata event new formdata(formelem); }); when the formdata event fires we can access the formdata object using formdataevent.formdata, then do what we like with it (below we post it to the server using xmlhttprequest).
... formelem.addeventlistener('formdata', (e) => { console.log('formdata fired'); // get the form data from the event object let data = e.formdata; for (var value of data.values()) { console.log(value); } // submit the data via xhr let request = new xmlhttprequest(); request.open("post", "/formhandler"); request.send(data); }); note: the formdata event and formdataevent object are available in chrome from version 77 (and other equivalent chromiums), and firefox 72 (first available behind the dom.formdata.event.enabled pref in firefox 71).
HTMLElement: animationend event - Web APIs
bubbles yes cancelable no interface animationevent event handler property onanimationend examples this example gets an element that's being animated and listens for the animationend event: const animated = document.queryselector('.animated'); animated.addeventlistener('animationend', () => { console.log('animation ended'); }); the same, but using the onanimationend event handler property: const animated = document.queryselector('.animated'); animated.onanimationend = () => { console.log('animation ended'); }; live example html <div class="animation-example"> <div class="container"> <p class="animation">you chose a cold night to visit our ...
...: 2; } @keyframes slidein { from { margin-left: 100%; width: 300%; } to { margin-left: 0%; width: 100%; } } js const animation = document.queryselector('p.animation'); const animationeventlog = document.queryselector('.animation-example>.event-log'); const applyanimation = document.queryselector('.animation-example>button.activate'); let iterationcount = 0; animation.addeventlistener('animationstart', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation started' `; }); animation.addeventlistener('animationiteration', () => { iterationcount++; animationeventlog.textcontent = `${animationeventlog.textcontent}'animation iterations: ${iterationcount}' `; }); animation.addeventlistener('animationend', () => { animationeventlog.textcontent =...
... `${animationeventlog.textcontent}'animation ended'`; animation.classlist.remove('active'); applyanimation.textcontent = "activate animation"; }); animation.addeventlistener('animationcancel', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation canceled'`; }); applyanimation.addeventlistener('click', () => { animation.classlist.toggle('active'); animationeventlog.textcontent = ''; iterationcount = 0; let active = animation.classlist.contains('active'); if (active) { applyanimation.textcontent = "cancel animation"; } else { applyanimation.textcontent = "activate animation"; } }); result specifications specification status comment css animations working draft initial definition ...
HTMLElement: animationiteration event - Web APIs
bubbles yes cancelable no interface animationevent event handler property onanimationiteration examples this code uses animationiteration to keep track of the number of iterations an animation has completed: const animated = document.queryselector('.animated'); let iterationcount = 0; animated.addeventlistener('animationiteration', () => { iterationcount++; console.log(`animation iteration count: ${iterationcount}`); }); the same, but using the onanimationiteration event handler property: const animated = document.queryselector('.animated'); let iterationcount = 0; animated.onanimationiteration = () => { iterationcount++; console.log(`animation iteration count: ${iterationcount}`); }; live...
... } @keyframes slidein { from { transform: translatex(100%) scalex(3); } to { transform: translatex(0) scalex(1); } } js const animation = document.queryselector('p.animation'); const animationeventlog = document.queryselector('.animation-example>.event-log'); const applyanimation = document.queryselector('.animation-example>button.activate'); let iterationcount = 0; animation.addeventlistener('animationstart', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation started' `; }); animation.addeventlistener('animationiteration', () => { iterationcount++; animationeventlog.textcontent = `${animationeventlog.textcontent}'animation iterations: ${iterationcount}' `; }); animation.addeventlistener('animationend', () => { animationeventlog.textcontent =...
... `${animationeventlog.textcontent}'animation ended'`; animation.classlist.remove('active'); applyanimation.textcontent = "activate animation"; }); animation.addeventlistener('animationcancel', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation canceled'`; }); applyanimation.addeventlistener('click', () => { animation.classlist.toggle('active'); animationeventlog.textcontent = ''; iterationcount = 0; let active = animation.classlist.contains('active'); if (active) { applyanimation.textcontent = "cancel animation"; } else { applyanimation.textcontent = "activate animation"; } }); result specifications specification status comment css animations working draft initial definition ...
HTMLElement: animationstart event - Web APIs
bubbles yes cancelable no interface animationevent event handler property onanimationstart examples this listens for the animationstart event and logs a message when it is fired: const animated = document.queryselector('.animated'); animated.addeventlistener('animationstart', () => { console.log('animation started'); }); the same, but using onanimationstart: const animated = document.queryselector('.animated'); animated.onanimationstart = () => { console.log('animation started'); }; live example html <div class="animation-example"> <div class="container"> <p class="animation">you chose a cold night to visit our planet.</p> ...
... } @keyframes slidein { from { transform: translatex(100%) scalex(3); } to { transform: translatex(0) scalex(1); } } js const animation = document.queryselector('p.animation'); const animationeventlog = document.queryselector('.animation-example>.event-log'); const applyanimation = document.queryselector('.animation-example>button.activate'); let iterationcount = 0; animation.addeventlistener('animationstart', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation started' `; }); animation.addeventlistener('animationiteration', () => { iterationcount++; animationeventlog.textcontent = `${animationeventlog.textcontent}'animation iterations: ${iterationcount}' `; }); animation.addeventlistener('animationend', () => { animationeventlog.textcontent =...
... `${animationeventlog.textcontent}'animation ended'`; animation.classlist.remove('active'); applyanimation.textcontent = "activate animation"; }); animation.addeventlistener('animationcancel', () => { animationeventlog.textcontent = `${animationeventlog.textcontent}'animation canceled'`; }); applyanimation.addeventlistener('click', () => { animation.classlist.toggle('active'); animationeventlog.textcontent = ''; iterationcount = 0; let active = animation.classlist.contains('active'); if (active) { applyanimation.textcontent = "cancel animation"; } else { applyanimation.textcontent = "activate animation"; } }); result specifications specification status comment css animations working draft initial definition ...
IDBRequest: error event - Web APIs
cancelable no interface event event handler property onerror examples this example opens a database and tries to add a record, listening for the error event for the add() operation (this will occur if, for example, a record with the given tasktitle already exists): // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.addeventlistener('upgradeneeded', event => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.cr...
...eateindex('minutes', 'minutes', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }); dbopenrequest.addeventlistener('success', event => { const db = dbopenrequest.result; // open a read/write db transaction, ready for adding the data const transaction = db.transaction(['todolist'], 'readwrite'); const objectstore = transaction.objectstore('todolist'); const newitem = { tasktitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'january', year: 2020 }; const objectstorerequest = objectstore.add(newitem); objectstorerequest.addeventlistener('error', () => { console.log(`error adding new item: ${newitem.tasktitle}`); }); }); t...
...he same example, using the onerror property instead of addeventlistener(): // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.onupgradeneeded = event => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes', 'minutes', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; db...
KeyboardEvent.code - Web APIs
examples exercising keyboardevent html <p>press keys on the keyboard to see what the keyboardevent's key and code values are for each one.</p> <div id="output"> </div> css #output { font-family: arial, helvetica, sans-serif; border: 1px solid black; } javascript window.addeventlistener("keydown", function(event) { let str = "keyboardevent: key='" + event.key + "' | code='" + event.code + "'"; let el = document.createelement("span"); el.innerhtml = str + "<br/>"; document.getelementbyid("output").appendchild(el); }, true); try it out to ensure that keystrokes go to the sample, click in the output box below before pressing keys.
... function refresh() { let x = position.x - (shipsize.width/2); let y = position.y - (shipsize.height/2); let transform = "translate(" + x + " " + y + ") rotate(" + angle + " 15 15) "; spaceship.setattribute("transform", transform); } finally, the addeventlistener() method is used to start listening for keydown events, acting on each key by updating the ship position and rotation angle, then calling refresh() to draw the ship at its new position and angle.
... window.addeventlistener("keydown", function(event) { if (event.defaultprevented) { return; // do nothing if event already handled } switch(event.code) { case "keys": case "arrowdown": // handle "back" updateposition(-moverate); break; case "keyw": case "arrowup": // handle "forward" updateposition(moverate); break; case "keya": case "arrowleft": // handle "turn left" angle -= turnrate; break; case "keyd": case "arrowright": // handle "turn right" angle += turnrate; break; } refresh(); // consume the event so it doesn't get handled twice event.preventdefault(); }, true); try it out to ensure that keystrokes go to the sample code, click inside the black game play field below befor...
MediaQueryList - Web APIs
this method exists primarily for backward compatibility; if possible, you should instead use addeventlistener() to watch for the change event.
...this method has been kept for backward compatibility; if possible, you should generally use removeeventlistener() to remove change notification callbacks (which should have previously been added using addeventlistener()).
... { if (e.matches) { /* the viewport is 600 pixels wide or less */ para.textcontent = 'this is a narrow screen — less than 600px wide.'; document.body.style.backgroundcolor = 'red'; } else { /* the viewport is more than than 600 pixels wide */ para.textcontent = 'this is a wide screen — more than 600px wide.'; document.body.style.backgroundcolor = 'blue'; } } mql.addeventlistener('change', screentest); note: you can find this example on github (see the source code, and also see it running live).
MessagePort: messageerror event - Web APIs
he ports to a different browsing context, such as another <iframe>, using code like this: const channel = new messagechannel(); const myport = channel.port1; const targetframe = window.top.frames[1]; const targetorigin = 'https://example.org'; const messagecontrol = document.queryselector('#message'); const channelmessagebutton = document.queryselector('#channel-message'); channelmessagebutton.addeventlistener('click', () => { myport.postmessage(messagecontrol.value); }) targetframe.postmessage('init', targetorigin, [channel.port2]); the target can receive the port and start listening for messages and message errors on it using code like this: window.addeventlistener('message', (event) => { const myport = event.ports[0]; myport.addeventlistener('message', (event) => { received.t...
...extcontent = event.data; }); myport.addeventlistener('messageerror', (event) => { console.error(event.data); }); myport.start(); }); note that the listener must call messageport.start() before any messages will be delivered to this port.
... this is only needed when using the addeventlistener() method: if the receiver uses onmessage instead, start() is called implicitly: window.addeventlistener('message', (event) => { const myport = event.ports[0]; myport.onmessage = (event) => { received.textcontent = event.data; }; myport.onmessageerror = (event) => { console.error(event.data); }; }); specifications specification status html living standard living standard ...
Online and offline events - Web APIs
you can register listeners for these events in a few familiar ways: using addeventlistener on the window, document, or document.body by setting the .ononline or .onoffline properties on document or document.body to a javascript function object.
... here's the javascript part: window.addeventlistener('load', function() { var status = document.getelementbyid("status"); var log = document.getelementbyid("log"); function updateonlinestatus(event) { var condition = navigator.online ?
... "online" : "offline"; status.classname = condition; status.innerhtml = condition.touppercase(); log.insertadjacenthtml("beforeend", "event: " + event.type + "; status: " + condition); } window.addeventlistener('online', updateonlinestatus); window.addeventlistener('offline', updateonlinestatus); }); a touch of css #status { position: fixed; width: 100%; font: bold 1em sans-serif; color: #fff; padding: 0.5em; } #log { padding: 2.5em 0.5em 0.5em; font: 1em sans-serif; } .online { background: green; } .offline { background: red; } and the corresponding htmlxxx when mochitests for this are created, point to those instead and update this example -nickolay <div id="status"></div> <div id="log"></div> <p>this is a test</p> here's the live result notes if the...
Using the Payment Request API - Web APIs
const checkoutbutton = document.getelementbyid('checkout-button'); if (window.paymentrequest) { let request = new paymentrequest(buildsupportedpaymentmethodnames(), buildshoppingcartdetails()); checkoutbutton.addeventlistener('click', function() { request.show().then(function(paymentresponse) { // handle successful payment }).catch(function(error) { // handle cancelled or failed payment.
... the code looks something like this: checkoutbutton.addeventlistener('click', function() { var request = new paymentrequest(buildsupportedpaymentmethoddata(), buildshoppingcartdetails()); request.show().then(function(paymentresponse) { // here we would process the payment.
... }); the payment handler would include the following code: self.addeventlistener('canmakepayment', function(evt) { // pre-authorize here.
Sensor APIs - Web APIs
let accelerometer = null; try { accelerometer = new accelerometer({ referenceframe: 'device' }); accelerometer.addeventlistener('error', event => { // handle runtime errors.
... } else if (event.error.name === 'notreadableerror' ) { console.log('cannot connect to the sensor.'); } }); accelerometer.addeventlistener('reading', () => reloadonshake(accelerometer)); accelerometer.start(); } catch (error) { // handle construction errors.
... let magsensor = new magnetometer({frequency: 60}); magsensor.addeventlistener('reading', e => { console.log("magnetic field along the x-axis " + magsensor.x); console.log("magnetic field along the y-axis " + magsensor.y); console.log("magnetic field along the z-axis " + magsensor.z); }) magsensor.addeventlistener('error', event => { console.log(event.error.name, event.error.message); }) magsensor.start(); interfaces absoluteorientationsensorsecure context des...
SubtleCrypto.deriveBits() - Web APIs
rivatekey, publickey) { const sharedsecret = await window.crypto.subtle.derivebits( { name: "ecdh", namedcurve: "p-384", public: publickey }, privatekey, 128 ); const buffer = new uint8array(sharedsecret, 0, 5); const sharedsecretvalue = document.queryselector(".ecdh .derived-bits-value"); sharedsecretvalue.classlist.add("fade-in"); sharedsecretvalue.addeventlistener("animationend", () => { sharedsecretvalue.classlist.remove("fade-in"); }); sharedsecretvalue.textcontent = `${buffer}...[${sharedsecret.bytelength} bytes total]`; } // generate 2 ecdh key pairs: one for alice and one for bob // in more normal usage, they would generate their key pairs // separately and exchange public keys securely const generatealiceskeypair = window.crypto.subtle.gener...
...ivebits"] ); const generatebobskeypair = window.crypto.subtle.generatekey( { name: "ecdh", namedcurve: "p-384" }, false, ["derivebits"] ); promise.all([generatealiceskeypair, generatebobskeypair]).then(values => { const aliceskeypair = values[0]; const bobskeypair = values[1]; const derivebitsbutton = document.queryselector(".ecdh .derive-bits-button"); derivebitsbutton.addeventlistener("click", () => { // alice then generates a secret using her private key and bob's public key.
...); const derivedbits = await window.crypto.subtle.derivebits( { "name": "pbkdf2", salt: salt, "iterations": 100000, "hash": "sha-256" }, keymaterial, 256 ); const buffer = new uint8array(derivedbits, 0, 5); const derivedbitsvalue = document.queryselector(".pbkdf2 .derived-bits-value"); derivedbitsvalue.classlist.add("fade-in"); derivedbitsvalue.addeventlistener("animationend", () => { derivedbitsvalue.classlist.remove("fade-in"); }); derivedbitsvalue.textcontent = `${buffer}...[${derivedbits.bytelength} bytes total]`; } const derivebitsbutton = document.queryselector(".pbkdf2 .derive-bits-button"); derivebitsbutton.addeventlistener("click", () => { getderivedbits(); }); specifications specification status comment web...
VisualViewport - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the relevant oneventname property of this interface.
... var bottombar = document.getelementbyid('bottombar'); var viewport = window.visualviewport; function resizehandler() { if (viewport.scale > 1.3) bottombar.style.display = "none"; else bottombar.style.display = "block"; } window.visualviewport.addeventlistener('resize', resizehandler); simulating position: device-fixed this example, also taken from the visual viewport readme, shows how to use this api to simulate position: device-fixed, which fixes elements to the visual viewport.
... bottombar.style.transform = 'translate(' + offsetleft + 'px,' + offsettop + 'px) ' + 'scale(' + 1/viewport.scale + ')' } window.visualviewport.addeventlistener('scroll', viewporthandler); window.visualviewport.addeventlistener('resize', viewporthandler); note: this technique should be used with care; emulating position: device-fixed in this way can result in the fixed element flickering during scrolling.
Hello vertex attributes - Web APIs
/x-vertex" id="vertex-shader"> #version 100 precision highp float; attribute float position; void main() { gl_position = vec4(position, 0.0, 0.0, 1.0); gl_pointsize = 64.0; } </script> <script type="x-shader/x-fragment" id="fragment-shader"> #version 100 precision mediump float; void main() { gl_fragcolor = vec4(0.18, 0.54, 0.34, 1.0); } </script> ;(function(){ "use strict" window.addeventlistener("load", setupwebgl, false); var gl, program; function setupwebgl (evt) { window.removeeventlistener(evt.type, setupwebgl, false); if (!(gl = getrenderingcontext())) return; var source = document.queryselector("#vertex-shader").innerhtml; var vertexshader = gl.createshader(gl.vertex_shader); gl.shadersource(vertexshader,source); gl.compileshader(vertexshader); source = documen...
..." + "error log: " + linkerrlog; return; } initializeattributes(); gl.useprogram(program); gl.drawarrays(gl.points, 0, 1); document.queryselector("canvas").addeventlistener("click", function (evt) { var clickxrelativtocanvas = evt.pagex - evt.target.offsetleft; var clickxinwebglcoords = 2.0 * (clickxrelativtocanvas- gl.drawingbufferwidth/2) / gl.drawingbufferwidth; gl.bufferdata(gl.array_buffer, new float32array([clickxinwebglcoords]), gl.static_draw); gl.drawarrays(gl.points, 0, 1); }, false); } ...
... var buffer; function initializeattributes() { gl.enablevertexattribarray(0); buffer = gl.createbuffer(); gl.bindbuffer(gl.array_buffer, buffer); gl.bufferdata(gl.array_buffer, new float32array([0.0]), gl.static_draw); gl.vertexattribpointer(0, 1, gl.float, false, 0, 0); } window.addeventlistener("beforeunload", cleanup, true); function cleanup() { gl.useprogram(null); if (buffer) gl.deletebuffer(buffer); if (program) gl.deleteprogram(program); } function getrenderingcontext() { var canvas = document.queryselector("canvas"); canvas.width = canvas.clientwidth; canvas.height = canvas.clientheight; var gl = canvas.getcontext("webgl") || canvas.getcontext("experimental-webgl"); if (!gl) { var paragraph = document.queryselector("p"); paragraph.innerhtml = "fail...
Simple color animation - Web APIs
as.</canvas> <button id="animation-onoff"> press here to <strong>[verb goes here]</strong> the animation </button> body { text-align : center; } canvas { display : block; width : 280px; height : 210px; margin : auto; padding : 0; border : none; background-color : black; } button { display : inline-block; font-size : inherit; margin : auto; padding : 0.6em; } window.addeventlistener("load", function setupanimation (evt) { "use strict" window.removeeventlistener(evt.type, setupanimation, false); // a variable to hold a timer that drives the animation.
... var button = document.queryselector("#animation-onoff"); var verb = document.queryselector("strong"); function startanimation(evt) { button.removeeventlistener(evt.type, startanimation, false); button.addeventlistener("click", stopanimation, false); verb.innerhtml="stop"; // setup animation loop by redrawing every second.
... drawanimation(); } function stopanimation(evt) { button.removeeventlistener(evt.type, stopanimation, false); button.addeventlistener("click", startanimation, false); verb.innerhtml="start"; // stop animation by clearing the timer.
Taking still photos with WebRTC - Web APIs
the startup() function the startup() function is run when the page has finished loading, courtesy of window.addeventlistener().
... video.addeventlistener('canplay', function(ev){ if (!streaming) { height = video.videoheight / (video.videowidth/width); video.setattribute('width', width); video.setattribute('height', height); canvas.setattribute('width', width); canvas.setattribute('height', height); streaming = true; } }, false); this callback does nothing unless it's the first time ...
... handle clicks on the button to capture a still photo each time the user clicks the startbutton, we need to add an event listener to the button, to be called when the click event is issued: startbutton.addeventlistener('click', function(ev){ takepicture(); ev.preventdefault(); }, false); this method is simple enough: it just calls our takepicture() function, defined below in the section capturing a frame from the stream, then calls event.preventdefault() on the received event to prevent the click from being handled more than once.
Using the Web Animations API - Web APIs
nommingcake.play(); } when a user holds their mouse down or presses their finger on the cake on a touch screen, we can now call growalice to make all the animations play: cake.addeventlistener("mousedown", growalice, false); cake.addeventlistener("touchstart", growalice, false); other useful methods in addition to pausing and playing, we can use the following animation methods: animation.finish() skips to the end of the animation.
...this is because the bottle changes her animation’s playbackrate from 1 to -1: var shrinkalice = function() { alicechange.playbackrate = -1; alicechange.play(); } bottle.addeventlistener("mousedown", shrinkalice, false); bottle.addeventlistener("touchstart", shrinkalice, false); in through the looking-glass, alice travels to a world where she must run to stay in place — and run twice as fast to move forward!
... // make sure the playback rate never falls below .4 if (redqueen_alice.playbackrate > .4) { redqueen_alice.updateplaybackrate(redqueen_alice.playbackrate * .9); } }, 3000); but urging them on by clicking or tapping causes them to speed up by multiplying their playbackrate: var gofaster = function() { redqueen_alice.updateplaybackrate(redqueen_alice.playbackrate * 1.1); } document.addeventlistener("click", gofaster); document.addeventlistener("touchstart", gofaster); the background elements also have playbackrates that are impacted when you click or tap.
Example and tutorial: Simple synth keyboard - Web APIs
function setup() { notefreq = createnotetable(); volumecontrol.addeventlistener("change", changevolume, false); mastergainnode = audiocontext.creategain(); mastergainnode.connect(audiocontext.destination); mastergainnode.gain.value = volumecontrol.value; // create the keys; skip any that are sharp or flat; for // our purposes we don't need them.
... an event handler is established (by calling our old friend addeventlistener() to handle change events on the master gain control.
...ekey(note, octave, freq) { let keyelement = document.createelement("div"); let labelelement = document.createelement("div"); keyelement.classname = "key"; keyelement.dataset["octave"] = octave; keyelement.dataset["note"] = note; keyelement.dataset["frequency"] = freq; labelelement.innerhtml = note + "<sub>" + octave + "</sub>"; keyelement.appendchild(labelelement); keyelement.addeventlistener("mousedown", notepressed, false); keyelement.addeventlistener("mouseup", notereleased, false); keyelement.addeventlistener("mouseover", notepressed, false); keyelement.addeventlistener("mouseleave", notereleased, false); return keyelement; } after creating the elements that will represent the key and its label, we configure the key's element by setting its class to "key" (which establi...
window.postMessage() - Web APIs
the dispatched event otherwindow can listen for dispatched messages by executing the following javascript: window.addeventlistener("message", receivemessage, false); function receivemessage(event) { if (event.origin !== "http://example.org:8080") return; // ...
... the secret response is: rheeeeet!" } window.addeventlistener("message", receivemessage, false); /* * in the popup's scripts, running on <http://example.com>: */ // called sometime after postmessage is called function receivemessage(event) { // do we trust the sender of this message?
... the secret response " + "is: rheeeeet!", event.origin); } window.addeventlistener("message", receivemessage, false); notes any window may access this method on any other window, at any time, regardless of the location of the document in the window, to send it a message.
WindowEventHandlers.onbeforeunload - Web APIs
syntax window.addeventlistener("beforeunload", function(event) { ...
...}; typically, it is better to use window.addeventlistener() and the beforeunload event, instead of onbeforeunload.
... window.addeventlistener('beforeunload', function (e) { // cancel the event e.preventdefault(); // if you prevent default behavior in mozilla firefox prompt will always be shown // chrome requires returnvalue to be set e.returnvalue = ''; }); guarantee the browser unload by removing the returnvalue property of the event window.addeventlistener('beforeunload', function (e) { // the absence of a returnvalue property on the event will guarantee the browser unload happens delete e['returnvalue']; }); notes when your page uses javascript to render content, the javascript may stop when leaving a...
WindowEventHandlers.onhashchange - Web APIs
syntax using an event handler: window.onhashchange = funcref; using an html event handler: <body onhashchange="funcref();"> using an event listener: to add an event listener, use addeventlistener(): window.addeventlistener("hashchange", funcref, false); parameters funcref a reference to a function.
... function hashhandler() { console.log('the hash has changed!'); } window.addeventlistener('hashchange', hashhandler, false); overriding the hash this function sets a new hash dynamically, setting it randomly to one of two values.
... polyfill for event.newurl and event.oldurl // let this snippet run before your hashchange event binding code if (!window.hashchangeevent)(function(){ var lasturl = document.url; window.addeventlistener("hashchange", function(event){ object.defineproperty(event, "oldurl", {enumerable:true,configurable:true,value:lasturl}); object.defineproperty(event, "newurl", {enumerable:true,configurable:true,value:document.url}); lasturl = document.url; }); }()); specifications specification status comment html living standardthe definition of 'onhashchange' in th...
Media buffering, seeking, and time ranges - Developer guides
dio = document.getelementbyid('my-audio'); var mycanvas = document.getelementbyid('my-canvas'); var context = mycanvas.getcontext('2d'); context.fillstyle = 'lightgray'; context.fillrect(0, 0, mycanvas.width, mycanvas.height); context.fillstyle = 'red'; context.strokestyle = 'white'; var inc = mycanvas.width / myaudio.duration; // display timeranges myaudio.addeventlistener('seeked', function() { for (i = 0; i < myaudio.buffered.length; i++) { var startx = myaudio.buffered.start(i) * inc; var endx = myaudio.buffered.end(i) * inc; var width = endx - startx; context.fillrect(startx, 0, width, mycanvas.height); context.rect(startx, 0, width, mycanvas.height); context.stroke(); } }); } this works bette...
... block; height: 100%; background-color: #777; width: 0; } .progress { margin-top: -20px; height: 20px; position: relative; width: 300px; } #progress-amount { display: block; height: 100%; background-color: #595; width: 0; } and the following javascript provides our functionality: window.onload = function(){ var myaudio = document.getelementbyid('my-audio'); myaudio.addeventlistener('progress', function() { var duration = myaudio.duration; if (duration > 0) { for (var i = 0; i < myaudio.buffered.length; i++) { if (myaudio.buffered.start(myaudio.buffered.length - 1 - i) < myaudio.currenttime) { document.getelementbyid("buffered-amount").style.width = (myaudio.buffered.end(myaudio.buffered.length - 1 - i) / duration) * 100 + "%"; ...
... break; } } } }); myaudio.addeventlistener('timeupdate', function() { var duration = myaudio.duration; if (duration > 0) { document.getelementbyid('progress-amount').style.width = ((myaudio.currenttime / duration)*100) + "%"; } }); } the progress event is fired as data is downloaded, this is a good event to react to if we want to display download or buffering progress.
Audio and video manipulation - Developer guides
his.video.ended) { return; } this.computeframe(); var self = this; settimeout(function () { self.timercallback(); }, 16); // roughly 60 frames per second }, doload: function() { this.video = document.getelementbyid("my-video"); this.c1 = document.getelementbyid("my-canvas"); this.ctx1 = this.c1.getcontext("2d"); var self = this; this.video.addeventlistener("play", function() { self.width = self.video.width; self.height = self.video.height; self.timercallback(); }, false); }, computeframe: function() { this.ctx1.drawimage(this.video, 0, 0, this.width, this.height); var frame = this.ctx1.getimagedata(0, 0, this.width, this.height); var l = frame.data.length / 4; for (var i = 0; i < l; i++) { var grey ...
... type="button" value="reset" /> </div> <textarea id="code" class="playable-code"> var myvideo = document.getelementbyid('my-video'); myvideo.playbackrate = 2;</textarea> var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var edit = document.getelementbyid('edit'); var code = textarea.value; function setplaybackrate() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; setplaybackrate(); }); edit.addeventlistener('click', function() { textarea.focus(); }) textarea.addeventlistener('input', setplaybackrate); window.addeventlistener('load', setplaybackrate); note: try the playbackrate example live.
...createmediaelementsource(document.getelementbyid("my-video")), filter = context.createbiquadfilter(); audiosource.connect(filter); filter.connect(context.destination); var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var edit = document.getelementbyid('edit'); var code = textarea.value; function setfilter() { eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; setfilter(); }); edit.addeventlistener('click', function() { textarea.focus(); }) textarea.addeventlistener('input', setfilter); window.addeventlistener('load', setfilter); note: unless you have cors enabled, to avoid security issues your video should be on the same domain as your code.
DOM onevent handlers - Developer guides
two common approaches are addeventlistener() and the specific onevent handlers.
...in order to allow multiple handlers to be installed for the same event on a given object, you can call its addeventlistener() method, which manages a list of handlers for the given event on the object.
... when discussing the various methods of listening to events: event listener refers to a function or object registered via eventtarget.addeventlistener() event handler refers to a function registered via on… attributes or properties specifications specification status comment html living standardthe definition of 'event handlers' in that specification.
Overview of events and handlers - Developer guides
browsers use as the registration method for the function which will handle those data structures a method called addeventlistener which expects as arguments a string event type name and the handler function.
..."eventprototype" : "objectprototype"; alert("we got a click event at " + ev.timestamp + " with an argument object derived from: " + objkind ); }; and second register our function with the the button object, either on the scripting side using the dom (document object model) representation of the html page: var buttondomelement = document.queryselector('#buttonone'); buttondomelement.addeventlistener('click', example_click_handler); or within the html page by adding the function as the value of the 'onclick' attribute, although this second approach is usually only used in very simple web pages.
...for example, code might be attached as: var funcinit = function(){ // user code goes here and can safely address all the html elements from the page // since the document has successfully been 'loaded' } document.addeventlistener('domcontentloaded', funcinit); so that this code will only be executed after the document object emits the 'domcontentloaded' event because the html has been parsed and javasript objects created representing each of the nodes of the html document.
How to make PWAs re-engageable using Notifications and Push - Progressive web apps (PWAs)
instead of showing the notification immediately though, best practice dictates that we should show the popup when the user requests it by clicking on a button: var button = document.getelementbyid("notifications"); button.addeventlistener('click', function(e) { notification.requestpermission().then(function(result) { if(result === 'granted') { randomnotification(); } }); }); this shows a popup using the operating system’s own notifications service: when the user confirms to receive notifications, the app can then show them.
... to receive push messages, we can listen to the push event in the service worker file: self.addeventlistener('push', function(e) { /* ...
... ttl: req.body.ttl }; settimeout(function() { webpush.sendnotification(subscription, payload, options) .then(function() { res.sendstatus(201); }) .catch(function(error) { console.log(error); res.sendstatus(500); }); }, req.body.delay * 1000); }); }; service-worker.js the last file we will look at is the service worker: self.addeventlistener('push', function(event) { const payload = event.data ?
Structural overview of progressive web apps - Progressive web apps (PWAs)
var button = document.getelementbyid("notifications"); button.addeventlistener('click', function(e) { notification.requestpermission().then(function(result) { if (result === 'granted') { randomnotification(); } }); }); the randomnotification() function follows, rounding out the last of the code in the file: function randomnotification() { var randomitem = math.floor(math.random()*games.length); var notiftitle = games[randomitem].name; var notifbod...
... self.addeventlistener('install', function(e) { console.log('[service worker] install'); e.waituntil( caches.open(cachename).then(function(cache) { console.log('[service worker] caching all: app shell and content'); return cache.addall(contenttocache); }) ); }); with that done, we implement the service worker's fetch event handler; its job is to return the contents of the specified file, eit...
...her from the cache or by loading it over the network (caching it upon doing so): self.addeventlistener('fetch', function(e) { e.respondwith( caches.match(e.request).then(function(r) { console.log('[service worker] fetching resource: '+e.request.url); return r || fetch(e.request).then(function(response) { return caches.open(cachename).then(function(cache) { console.log('[service worker] caching new resource: '+e.request.url); cache.put(e.request, response.clone()); return response; }); }); }) ); }); auxiliary javascript file: games.js the games data for this app example is provided in a javascript source file called games.js.
Scripting - SVG: Scalable Vector Graphics
WebSVGScripting
one can override default browser behaviors with the evt.preventdefault( ) method, add eventlisteners to objects with the syntax element.addeventlistener(event, function, usecapture), and set element properties with syntax svgelement.style.setproperty("fill-opacity", "0.0", "").
... using eventlisteners with objects the methods addeventlistener() and removeeventlistener() are very useful when writing interactive svg.
... function myrect(x,y,w,h,message){ this.message=message this.rect=document.createelementns("http://www.w3.org/2000/svg","rect") this.rect.setattributens(null,"x",x) this.rect.setattributens(null,"y",y) this.rect.setattributens(null,"width",w) this.rect.setattributens(null,"height",h) document.documentelement.appendchild(this.rect) this.rect.addeventlistener("click",this,false) this.handleevent= function(evt){ switch (evt.type){ case "click": alert(this.message) break; } } } inter-document scripting: referencing embedded svg when using svg within html, adobe's svg viewer 3.0 automatically includes a window property called svgdocument that points to the svg document.
HTML to DOM - Archive of obsolete content
d(frame); // or // document.documentelement.appendchild(frame); // set restrictions as needed frame.webnavigation.allowauth = false; frame.webnavigation.allowimages = false; frame.webnavigation.allowjavascript = false; frame.webnavigation.allowmetaredirects = true; frame.webnavigation.allowplugins = false; frame.webnavigation.allowsubframes = false; // listen for load frame.addeventlistener("load", function (event) { // the document of the html in the dom var doc = event.originaltarget; // skip blank page or frame if (doc.location.href == "about:blank" || doc.defaultview.frameelement) return; // do something with the dom of doc alert(doc.location.href); // when done remove frame or set location "about:blank" settimeout(function (){ var frame =...
...ser"); if (donkeybrowser) { donkeybrowser.style.height = "0px"; donkeybrowser.webnavigation.allowauth = true; donkeybrowser.webnavigation.allowimages = false; donkeybrowser.webnavigation.allowjavascript = false; donkeybrowser.webnavigation.allowmetaredirects = true; donkeybrowser.webnavigation.allowplugins = false; donkeybrowser.webnavigation.allowsubframes = false; donkeybrowser.addeventlistener("domcontentloaded", function (e) { donkeyfire.donkeybrowser_onpageload(e); }, true); } with that code, we obtain a reference to the iframe element we declared in the .xul file.
Communication between HTML and your extension - Archive of obsolete content
i wasn't sure about the difference between the capture or bubbling flag that you pass to addeventlistener but every time i would catch the event in the extension, the element from the ajax request wasn't fully updated into the html page.
... if (doc && doc.addeventlistener) doc.addeventlistener("my-custom-event", myextension.customreceived, false); since the event is dispatched after the element in the html is updated by the statuschanged function, the element that extension is looking for is there to find.
Appendix F: Monitoring DOM changes - Archive of obsolete content
from { clip: rect(1px, auto, auto, auto); } to { clip: rect(0px, auto, auto, auto); } \n\ }\n'; let properties = [ 'animation-duration: 0.0001s;', 'animation-name: ' + event + ' !important;' ]; properties = properties.map(function (prop) ' ' + watchnodes.namespace + prop) .join('\n'); doc.addeventlistener('animationstart', listener, false); function listener(event) { if (event.animationname == event) callback.call(this, event); } style.textcontent = ' ' + preamble + selector + '{' + properties + '}'; (doc.head || doc.documentelement).appendchild(style); // this will only work in chrome privileged code.
...'-moz-' : ''; watchnodes.prefix = 'keyframe-node-inserted-' + math.floor(math.random() + 0xffffffff) + '-'; watchnodes._i = 0; } else { watchnodes = function watchnodes(selector, callback, doc) { doc = doc || document; doc.addeventlistener('domnodeinserted', listener, false); function listener(event) { if (event.target.mozmatchesselector(selector)) callback.call(this, event); } return function unwatch() { doc.removeeventlistener('domnodeinserted', listener, false); }; } } xbl xbl is similar in approach to the above animation-based method.
Appendix E: DOM Building and Insertion (HTML & XUL) - Archive of obsolete content
ck) for (var key in elemattr) { var val = elemattr[key]; if (nodes && key == "key") { nodes[val] = elem; continue; } var attrns = namespace(key); if (typeof val == "function") { // special case for function attributes; don't just add them as 'on...' attributes, but as events, using addeventlistener elem.addeventlistener(key.replace(/^on/, ""), val, false); } else { // note that the default namespace for xml attributes is, and should be, blank (ie.
...the following two code fragments are roughly equivalent: function clickify(elem, address) { elem.addeventlistener("click", function (event) { openwindow(address) }, false); } function clickify(elem, address) { elem.onclick = function (event) { openwindow(address) }; } multiple attributes sometimes there is a need for event listeners to appear as attributes in the dom.
Intercepting Page Loads - Archive of obsolete content
this._loadhandler = function() {that._onpageload(); }; gbrowser.addeventlistener("load", this._loadhandler, true); gbrowser is a global object that corresponds to the tabbrowser element in the main browser window.
...here's a code sample that keeps track of your progress listeners for all tabs: init : function() { gbrowser.browsers.foreach(function (browser) { this._toggleprogresslistener(browser.webprogress, true); }, this); gbrowser.tabcontainer.addeventlistener("tabopen", this, false); gbrowser.tabcontainer.addeventlistener("tabclose", this, false); }, uninit : function() { gbrowser.browsers.foreach(function (browser) { this ._toggleprogresslistener(browser.webprogress, false); }, this); gbrowser.tabcontainer.removeeventlistener("tabopen", this, false); gbrowser.tabcontainer.removeeventlistener("tabclose", this, false); }, handleevent :...
Index - Archive of obsolete content
you can use window.addeventlistener() to listen for these events in order to keep abreast of changes to toolbars.
...the events listeners can be attached using addeventlistener and removed using removeeventlistener.
JavaScript crypto - Archive of obsolete content
you can then register event handlers for these events with the document.addeventlistener() method.
...<script> function onsmartcardchange() { window.location.reload(); } function register() { window.crypto.enablesmartcardevents = true; document.addeventlistener("smartcard-insert", onsmartcardchange, false); document.addeventlistener("smartcard-remove", onsmartcardchange, false); } function deregister() { document.removeeventlistener("smartcard-insert", onsmartcardchange, false); document.removeeventlistener("smartcard-remove", onsmartcardchange, false); } document.body.onload = register; document.body.onunload = deregister; </script> with the a...
XUL Events - Archive of obsolete content
the events listeners can be attached using addeventlistener and removed using removeeventlistener.
... window events the following events are dispatched to top-level dom windows and can be listened to using window.addeventlistener.
Index - Archive of obsolete content
ArchiveMozillaXULIndex
you can use window.addeventlistener() to listen for these events in order to keep abreast of changes to toolbars.
...the events listeners can be attached using addeventlistener and removed using removeeventlistener.
ContextMenus - Archive of obsolete content
function checkcontextmenu(event) { if (event.target.localname == "textbox") event.preventdefault(); } function init() { var container = document.getelementbyid("container"); container.addeventlistener("contextmenu", checkcontextmenu, true); } the 'checkcontextmenu' function checks to see if the textbox was the target of the context menu and, if so, cancels the event using the preventdefault method.
...the event listener is attached using the addeventlistener method within the 'init' function.
PopupEvents - Archive of obsolete content
<script> function openfilemenu() { var filemenu = document.getelementbyid("file-menu"); filemenu.addeventlistener("popupshown", filemenuopened, false); filemenu.open = true; } function filemenuopened(event) { if (event.target != document.getelementbyid("file-menupopup")) return; var filemenu = document.getelementbyid("file-menu"); filemenu.removeeventlistener("popupshown", filemenuopened, false); var openmenu = document.getelementbyid("open-menu"); openmenu.open = true; } </script> <menu ...
...within this function, a popupshown event listener is attached to the 'file' menu using the addeventlistener method.
Toolbar customization events - Archive of obsolete content
you can use window.addeventlistener() to listen for these events in order to keep abreast of changes to toolbars.
...window.addeventlistener("beforecustomization", customizestart, false); window.addeventlistener("aftercustomization", customizeend, false); window.addeventlistener("customizationchange", customizechange, false); function customizestart(e) { let thetoolbox = e.target; /* now we know the user has started customizing */ } function customizeend(e) { let thetoolbox = e.target; /* the user has finished customizing */...
More Event Handlers - Archive of obsolete content
in the addeventlistener form, the first argument passed to the listener function will be the event object.
...example 2 : source view <hbox id="outerbox"> <button id="okbutton" label="ok"/> </hbox> <script> function buttonpressed(event){ alert('button was pressed!'); } function boxpressed(event){ alert('box was pressed!'); event.stoppropagation(); } var button = document.getelementbyid("okbutton"); button.addeventlistener('command',buttonpressed,true); var outerbox = document.getelementbyid("outerbox"); outerbox.addeventlistener('command',boxpressed,true); </script> here, an event listener has been added to the button and another event listener has been added to the box.
Audio for Web games - Game development
let's add some javascript to make this work: var myaudio = document.getelementbyid('myaudio'); var buttons = document.getelementsbytagname('button'); var stoptime = 0; for (var i = 0; i < buttons.length; i++) { buttons[i].addeventlistener('click', function() { myaudio.currenttime = this.getattribute("data-start"); stoptime = this.getattribute("data-stop"); myaudio.play(); }, false); } myaudio.addeventlistener('timeupdate', function() { if (this.currenttime > stoptime) { this.pause(); } }, false); note: you can try out our audio sprite player live on jsfiddle.
...selector('a'); const loadtext = el.queryselector('p'); const playbutton = el.queryselector('button'); // load file loadfile(anchor.href).then((track) => { // set loading to false el.dataset.loading = 'false'; // hide loading text loadtext.style.display = 'none'; // show button playbutton.style.display = 'inline-block'; // allow play on click playbutton.addeventlistener('click', function() { // check if context is in suspended state (autoplay policy) if (audioctx.state === 'suspended') { audioctx.resume(); } playtrack(track); playbutton.dataset.playing = true; }) }) }) note: you can see this demo in action here and view the source code here.
Desktop gamepad controls - Game development
first, we need an event listener to listen for the connection of the new device: window.addeventlistener("gamepadconnected", gamepadhandler); it's executed once, so we can create some variables we will need later on for storing the controller info and the pressed buttons: var controller = {}; var buttonspressed = []; function gamepadhandler(e) { controller = e.gamepad; output.innerhtml = "gamepad: " + controller.id; } the second line in the gamepadhandler function shows up on the screen w...
...the connect() and disconnect() functions are bound to the following events: window.addeventlistener("gamepadconnected", gamepadapi.connect); window.addeventlistener("gamepaddisconnected", gamepadapi.disconnect); they are fired when the gamepad is connected and disconnected respectively.
Mobile touch controls - Game development
pure javascript approach we could implement touch events on our own — setting up event listeners and assigning relevant functions to them would be quite straightforward: var el = document.getelementsbytagname("canvas")[0]; el.addeventlistener("touchstart", handlestart); el.addeventlistener("touchmove", handlemove); el.addeventlistener("touchend", handleend); el.addeventlistener("touchcancel", handlecancel); this way, touching the game's <canvas> on the mobile screen would emit events, and thus we could manipulate the game in any way we want (for example, moving the space ship around).
...the function touchhandler will assign proper variables to the ship's position so that we can use it for both cases: when the player touches the screen but doesn't move it (touchstart), and when the finger is moved on the screen (touchmove): document.addeventlistener("touchstart", touchhandler); document.addeventlistener("touchmove", touchhandler); the touchhandler function looks like this: function touchhandler(e) { if(e.touches) { playerx = e.touches[0].pagex - canvas.offsetleft - playerwidth / 2; playery = e.touches[0].pagey - canvas.offsettop - playerheight / 2; output.innerhtml = "touch: "+ " x: " + playerx + ", y: " + playe...
Paddle and keyboard controls - Game development
add the following lines just above the setinterval() line at the bottom of your javascript: document.addeventlistener("keydown", keydownhandler, false); document.addeventlistener("keyup", keyuphandler, false); when the keydown event is fired on any of the keys on your keyboard (when they are pressed), the keydownhandler() function will be executed.
...add these to your code now, below the addeventlistener() lines: function keydownhandler(e) { if(e.key == "right" || e.key == "arrowright") { rightpressed = true; } else if(e.key == "left" || e.key == "arrowleft") { leftpressed = true; } } function keyuphandler(e) { if(e.key == "right" || e.key == "arrowright") { rightpressed = false; } else if(e.key == "left" || e.key == "arrowleft") { leftpressed = false; } } when we press a key down, this information is stored in a variable.
Styling links - Learn web development
mlcode = htmlinput.value; var csscode = cssinput.value; var output = document.queryselector(".output"); var solution = document.getelementbyid("solution"); var styleelem = document.createelement('style'); var headelem = document.queryselector('head'); headelem.appendchild(styleelem); function drawoutput() { output.innerhtml = htmlinput.value; styleelem.textcontent = cssinput.value; } reset.addeventlistener("click", function() { htmlinput.value = htmlcode; cssinput.value = csscode; drawoutput(); }); solution.addeventlistener("click", function() { htmlinput.value = htmlcode; cssinput.value = 'p {\n font-size: 1.2rem;\n font-family: sans-serif;\n line-height: 1.4;\n}\n\na {\n outline: none;\n text-decoration: none;\n padding: 2px 1px 0;\n}\n\na:link {\n color: #265301;\n}\n\na:visite...
...d {\n color: #437a16;\n}\n\na:focus {\n border-bottom: 1px solid;\n background: #bae498;\n}\n\na:hover {\n border-bottom: 1px solid;\n background: #cdfeaa;\n}\n\na:active {\n background: #265301;\n color: #cdfeaa;\n}'; drawoutput(); }); htmlinput.addeventlistener("input", drawoutput); cssinput.addeventlistener("input", drawoutput); window.addeventlistener("load", drawoutput); including icons on links a common practice is to include icons on links to provide more of an indicator as to what kind of content the link points to.
Styling lists - Learn web development
mlcode = htmlinput.value; var csscode = cssinput.value; var output = document.queryselector(".output"); var solution = document.getelementbyid("solution"); var styleelem = document.createelement('style'); var headelem = document.queryselector('head'); headelem.appendchild(styleelem); function drawoutput() { output.innerhtml = htmlinput.value; styleelem.textcontent = cssinput.value; } reset.addeventlistener("click", function() { htmlinput.value = htmlcode; cssinput.value = csscode; drawoutput(); }); solution.addeventlistener("click", function() { htmlinput.value = htmlcode; cssinput.value = 'ul {\n list-style-type: square;\n}\n\nul li, ol li {\n line-height: 1.5;\n}\n\nol {\n list-style-type: lower-alpha\n}'; drawoutput(); }); htmlinput.addeventlistener("input", drawoutput); cssinpu...
...t.addeventlistener("input", drawoutput); window.addeventlistener("load", drawoutput); ...
Example 3 - Learn web development
ct, show) { var optlist = select.queryselector('.optlist'); optlist.classlist.toggle('hidden'); } function highlightoption(select, option) { var optionlist = select.queryselectorall('.option'); optionlist.foreach(function (other) { other.classlist.remove('highlight'); }); option.classlist.add('highlight'); }; // ------------- // // event binding // // ------------- // window.addeventlistener("load", function () { var form = document.queryselector('form'); form.classlist.remove("no-widget"); form.classlist.add("widget"); }); window.addeventlistener('load', function () { var selectlist = document.queryselectorall('.select'); selectlist.foreach(function (select) { var optionlist = select.queryselectorall('.option'); optionlist.foreach(function (option) { opti...
...on.addeventlistener('mouseover', function () { highlightoption(select, option); }); }); select.addeventlistener('click', function (event) { toggleoptlist(select); }, false); select.addeventlistener('focus', function (event) { activeselect(select, selectlist); }); select.addeventlistener('blur', function (event) { deactivateselect(select); }); select.addeventlistener('keyup', function (event) { if (event.keycode === 27) { deactivateselect(select); } }); }); }); result ...
Example 5 - Learn web development
se'); }); optionlist[index].setattribute('aria-selected', 'true'); nativewidget.selectedindex = index; value.innerhtml = optionlist[index].innerhtml; highlightoption(select, optionlist[index]); }; function getindex(select) { var nativewidget = select.previouselementsibling; return nativewidget.selectedindex; }; // ------------- // // event binding // // ------------- // window.addeventlistener("load", function () { var form = document.queryselector('form'); form.classlist.remove("no-widget"); form.classlist.add("widget"); }); window.addeventlistener('load', function () { var selectlist = document.queryselectorall('.select'); selectlist.foreach(function (select) { var optionlist = select.queryselectorall('.option'), selectedindex = getindex(select); select.
...tabindex = 0; select.previouselementsibling.tabindex = -1; updatevalue(select, selectedindex); optionlist.foreach(function (option, index) { option.addeventlistener('mouseover', function () { highlightoption(select, option); }); option.addeventlistener('click', function (event) { updatevalue(select, index); }); }); select.addeventlistener('click', function (event) { toggleoptlist(select); }); select.addeventlistener('focus', function (event) { activeselect(select, selectlist); }); select.addeventlistener('blur', function (event) { deactivateselect(select); }); select.addeventlistener('keyup', function (event) { var length = optionlist.length, index = getindex(select); if (ev...
Adding vector graphics to the Web - Learn web development
; width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); const output = document.queryselector('.output'); let code = textarea.value; let userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...w solution'; } updatecode(); }); const htmlsolution = ''; let solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { const scrollpos = textarea.scrolltop; const caretpos = textarea.selectionstart; const front = (textarea.value).substring(0, caretpos); const back = (textarea.value).substring(textarea.selectionend, textarea.value.length); textarea.value = front + text + back; caretpos = caretpos + text.length; textarea.selectio...
From object to iframe — other embedding technologies - Learn web development
; width: 98%; } body { margin: 10px; background: #f5f9fa; } const textarea = document.getelementbyid('code'); const reset = document.getelementbyid('reset'); const solution = document.getelementbyid('solution'); const output = document.queryselector('.output'); let code = textarea.value; let userentry = textarea.value; function updatecode() { output.innerhtml = textarea.value; } reset.addeventlistener('click', function() { textarea.value = code; userentry = textarea.value; solutionentry = htmlsolution; solution.value = 'show solution'; updatecode(); }); solution.addeventlistener('click', function() { if(solution.value === 'show solution') { textarea.value = solutionentry; solution.value = 'hide solution'; } else { textarea.value = userentry; solution.value = 'sho...
...\n\n<iframe src="https://www.google.com/maps/embed?pb=!1m18!1m12!1m3!1d37995.65748333395!2d-2.273568166412784!3d53.473310471916975!2m3!1f0!2f0!3f0!3m2!1i1024!2i768!4f13.1!3m3!1m2!1s0x487bae6c05743d3d%3a0xf82fddd1e49fc0a1!2sthe+lowry!5e0!3m2!1sen!2suk!4v1518171785211" width="600" height="450" frameborder="0" style="border:0" allowfullscreen>\n</iframe>'; let solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // stop tab key tabbing out of textarea and // make it write a tab at the caret position instead textarea.onkeydown = function(e){ if (e.keycode === 9) { e.preventdefault(); insertatcaret('\t'); } if (e.keycode === 27) { textarea.blur(); } }; function insertatcaret(text) { const scrollpos = textarea.scrol...
General asynchronous programming concepts - Learn web development
in our simple-sync.html example (see it running live), we add a click event listener to a button so that when clicked, it runs a time-consuming operation (calculates 10 million dates then logs the final one to the console) and then adds a paragraph to the dom: const btn = document.queryselector('button'); btn.addeventlistener('click', () => { let mydate; for(let i = 0; i < 10000000; i++) { let date = new date(); mydate = date } console.log(mydate); let pelem = document.createelement('p'); pelem.textcontent = 'this is a newly-added paragraph.'; document.body.appendchild(pelem); }); when running the example, open your javascript console then click the button — you'll notice that the paragraph ...
... function expensiveoperation() { for(let i = 0; i < 1000000; i++) { ctx.fillstyle = 'rgba(0,0,255, 0.2)'; ctx.beginpath(); ctx.arc(random(0, canvas.width), random(0, canvas.height), 10, degtorad(0), degtorad(360), false); ctx.fill() } } fillbtn.addeventlistener('click', expensiveoperation); alertbtn.addeventlistener('click', () => alert('you clicked me!') ); if you click the first button and then quickly click the second one, you'll see that the alert does not appear until the circles have finished being rendered.
Cooperative asynchronous JavaScript: Timeouts and intervals - Learn web development
btn.addeventlistener('click', start); function start() { draw(); spinnercontainer.style.display = 'block'; btn.style.display = 'none'; settimeout(setendgame, random(5000,10000)); } note: you'll see this example is calling settimeout() without storing the return value.
... add the following function to your code next: function setendgame() { cancelanimationframe(raf); spinnercontainer.style.display = 'none'; result.style.display = 'block'; result.textcontent = 'players go!!'; document.addeventlistener('keydown', keyhandler); function keyhandler(e) { let isover = false; console.log(e.key); if (e.key === "a") { result.textcontent = 'player 1 won!!'; isover = true; } else if (e.key === "l") { result.textcontent = 'player 2 won!!'; isover = true; } if (isover) { document.removeeventlistener('keydown', keyhandler); settimeout(reset, 5...
Third-party APIs - Learn web development
searchform.addeventlistener('submit', submitsearch); now add the submitsearch() and fetchresults() function definitions, below the previous line: function submitsearch(e) { pagenumber = 0; fetchresults(e); } function fetchresults(e) { // use preventdefault() to stop the form submitting e.preventdefault(); // assemble the full url url = baseurl + '?api-key=' + key + '&page=' + pagenumber + '&q=' + sear...
... below the existing addeventlistener() call, add these two new ones, which cause the nextpage() and previouspage() functions to be invoked when the relevant buttons are clicked: nextbtn.addeventlistener('click', nextpage); previousbtn.addeventlistener('click', previouspage); below your previous addition, let's define the two functions — add this code now: function nextpage(e) { pagenumber++; fetchresults(e); }; fu...
Communicating with frame scripts
the example below sends a message named "my-e10s-extension-message", with a data payload containing details and tag properties, and exposes the event.target object as a cpow: // frame script addeventlistener("click", function (event) { sendasyncmessage("my-addon@me.org:my-e10s-extension-message", { details : "they clicked", tag : event.target.tagname }, { target : event.target }); }, false); to receive messages from content, a chrome script needs to add a message listener using the message manager's addmessagelistener() api.
...because a single message can be received by more than one listener, the return value of sendsyncmessage() is an array of all the values returned from every listener, even if it only contains a single value: // frame script addeventlistener("click", function (event) { var results = sendsyncmessage("my-addon@me.org:my-e10s-extension-message", { details : "they clicked", tag : event.target.tagname }); content.console.log(results[0]); // "value from chrome" }, false); like arguments, return values from sendsyncmessage() must be json-serializable, so chrome can't return functions.
PromiseWorker.jsm
self.addeventlistener('message', msg => worker.handlemessage(msg)); abstractworker is a base class for the worker, and it's designed to be used by derived class, which provides above four methods (dispatch, postmessage, close, and log).
...= require('resource://gre/modules/workers/promiseworker.js'); let worker = new promiseworker.abstractworker(); worker.dispatch = function(method, args = []) { return self[method](...args); }; worker.postmessage = function(...args) { self.postmessage(...args); }; worker.close = function() { self.close(); }; worker.log = function(...args) { dump('worker: ' + args.join(' ') + '\n'); }; self.addeventlistener('message', msg => worker.handlemessage(msg)); // start - my functionalities function resolvetest(shouldresolve) { if (shouldresolve) { return 'you sent to promiseworker argument of: `' + shouldresolve + '`'; } else { throw new error('you passed in a non-true value for shouldresolve argument and therefore this will reject the main thread promise'); } } main thread file bootstrap...
L20n Javascript API
ctx.addeventlistener(event: string, callback: function) register an event handler on the context instance.
... ctx.removeeventlistener(event: string, callback: function) remove an event listener previously registered with addeventlistener.
nsIMacDockSupport
= win.document.createelementns('http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul', 'menupopup'); macmenu.setattribute('id', 'mymacmenu'); var macmenuitem = win.document.createelementns('http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul', 'menuitem'); macmenuitem.setattribute('label', 'show most recent window'); macmenuitem.setattribute('id', 'mymacmenuitem'); macmenuitem.addeventlistener('command', function(){ var docksupport = cc['@mozilla.org/widget/macdocksupport;1'].getservice(ci.nsimacdocksupport); docksupport.activateapplication(true); services.wm.getmostrecentwindow(null).focus() }) macmenu.appendchild(macmenuitem); var mainpopupset = win.document.getelementbyid('mainpopupset'); mainpopupset.appendchild(macmenu); let dockmenuelement = macmenu; //document.getelementb...
...var macmenuitem = services.appshell.hiddendomwindow.document.createelementns('http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul', 'menuitem'); macmenuitem.setattribute('label', 'show most recent window'); macmenuitem.setattribute('id', 'mymacmenuitem'); macmenuitem.addeventlistener('command', function(){ var docksupport = cc['@mozilla.org/widget/macdocksupport;1'].getservice(ci.nsimacdocksupport); docksupport.activateapplication(true); services.wm.getmostrecentwindow(null).focus() }) services.appshell.hiddendomwindow.document.getelementbyid('menu_mac_dockmenu').appendchild(macmenuitem) this adds the "show most recent window" menuitem from the previous example as a thi...
nsIWindowMediator
var {cc: classes, ci: interfaces} = components; var windowlistener = { onopenwindow: function (awindow) { // wait for the window to finish loading let domwindow = awindow.queryinterface(ci.nsiinterfacerequestor).getinterface(ci.nsidomwindowinternal || ci.nsidomwindow); domwindow.addeventlistener("load", function () { domwindow.removeeventlistener("load", arguments.callee, false); //this removes this load function from the window //window has now loaded now do stuff to it //as example this will add a function to listen to tab select and will fire alert in that window if (domwindow.gbrowser && domwindow.gbrowser.tabcontainer) { ...
... domwindow.gbrowser.tabcontainer.addeventlistener('tabselect', function () { domwindow.alert('tab was selected') }, false); } }, false); }, onclosewindow: function (awindow) {}, onwindowtitlechange: function (awindow, atitle) {} }; //to register services.wm.addlistener(windowlistener); //services.wm.removelistener(windowlistener); //once you want to remove this listener execute removelistener, currently its commented out so you can copy paste this code in scratchpad and see it work native code only!calculatezposition a window wants to be moved in z-order.
customDBHeaders Preference
observe: function(amsgfolder, atopic, adata) { dump("here here!"); addcustomcolumnhandler(); } } function doonceloaded(){ var observerservice = components.classes["@mozilla.org/observer-service;1"].getservice(components.interfaces.nsiobserverservice); observerservice.addobserver(createdbobserver, "msgcreatedbview", false); window.document.getelementbyid('foldertree').addeventlistener("select",addcustomcolumnhandler,false); } window.addeventlistener("load",doonceloaded,false); dump(" ~ ~ ~ ~ end superfluous ~ ~ ~ ~ \n"); important be aware that only messages that are added to the .msf database after the customdbheaders pref is set will have the corresponding string property set on the msghdr.
... the attaching of the column handler through the observerservice object is some pretty new stuff, so i was using the addeventlistener("select"...) stuff as a backup.
Browser Console - Firefox Developer Tools
this example here makes it so that when you mouse over the "clear" button it will clear the browser console: components.utils.import("resource://devtools/shared/loader.jsm"); var hudservice = devtools.require("devtools/client/webconsole/hudservice"); var hud = hudservice.getbrowserconsole(); var clearbtn = hud.chromewindow.document.queryselector('.webconsole-clear-console-button'); clearbtn.addeventlistener('mouseover', function() { hud.jsterm.clearoutput(true); }, false); bonus features available for add-on sdk add-ons, the console api is available automatically.
...try running this code in the browser console's command line (remember that to send multiple lines to the browser console, use shift+enter): var newtabbrowser = gbrowser.getbrowserfortab(gbrowser.selectedtab); newtabbrowser.addeventlistener("load", function() { newtabbrowser.contentdocument.body.innerhtml = "<h1>this page has been eaten</h1>"; }, true); newtabbrowser.contentdocument.location.href = "https://mozilla.org/"; it adds a listener to the currently selected tab's load event that will eat the new page, then loads a new page.
Access debugging in add-ons - Firefox Developer Tools
the following items are accessible in the context of chrome://browser/content/debugger.xul (or, in version 23 beta, chrome://browser/content/devtools/debugger.xul): window.addeventlistener("debugger:editorloaded") - called when the read-only script panel loaded.
... window.addeventlistener("debugger:editorunloaded") relevant files: chrome://browser/content/devtools/debugger-controller.js chrome://browser/content/devtools/debugger-toolbar.js chrome://browser/content/devtools/debugger-view.js chrome://browser/content/devtools/debugger-panes.js unfortunately there is not yet any api to evaluate watches/expressions within the debugged scope, or highlight elements on the page that are referenced as variables in the debugged scope.
Intensive JavaScript - Firefox Developer Tools
ns = 50; const multiplier = 1000000000; var worker = new worker("js/calculate.js"); function dopointlesscomputationsinworker() { function handleworkercompletion(message) { if (message.data.command == "done") { pointlesscomputationsbutton.disabled = false; console.log(message.data.primes); worker.removeeventlistener("message", handleworkercompletion); } } worker.addeventlistener("message", handleworkercompletion, false); worker.postmessage({ "multiplier": multiplier, "iterations": iterations }); } the main difference here, compared with the original, is that we need to: create a worker send it a message when we are ready to calculate listen for a message called "done", which indicates that the worker has finished.
... then we need a new file "calculate.js", that looks like this: self.addeventlistener("message", go); function go(message) { var iterations = message.data.iterations; var multiplier = message.data.multiplier; primes = calculateprimes(iterations, multiplier); self.postmessage({ "command":"done", "primes": primes }); } function calculateprimes(iterations, multiplier) { var primes = []; for (var i = 0; i < iterations; i++) { var candidate = i * (multiplier * math.random()); var isprime = true; for (var c = 2; c <= math.sqrt(candidate); ++c) { if (candidate % c === 0) { // not prime isprime = false; break; } } if (isprime) { primes.push(candidate); } } return primes; } in the worker, we have to listen for ...
AbortSignal - Web APIs
events listen to this event using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
... var controller = new abortcontroller(); var signal = controller.signal; var downloadbtn = document.queryselector('.download'); var abortbtn = document.queryselector('.abort'); downloadbtn.addeventlistener('click', fetchvideo); abortbtn.addeventlistener('click', function() { controller.abort(); console.log('download aborted'); }); function fetchvideo() { ...
AbsoluteOrientationSensor - Web APIs
const options = { frequency: 60, referenceframe: 'device' }; const sensor = new absoluteorientationsensor(options); sensor.addeventlistener('reading', () => { // model is a three.js object instantiated elsewhere.
... model.quaternion.fromarray(sensor.quaternion).inverse(); }); sensor.addeventlistener('error', error => { if (event.error.name == 'notreadableerror') { console.log("sensor is not available."); } }); sensor.start(); permissions example using orientation sensors requires requesting permissions for multiple device sensors.
Ambient Light Events - Web APIs
this event can be captured at the window object level by using the addeventlistener method (using the devicelight event name) or by attaching an event handler to the window.ondevicelight property.
... example if ('ondevicelight' in window) { window.addeventlistener('devicelight', function(event) { var body = document.queryselector('body'); if (event.value < 50) { body.classlist.add('darklight'); body.classlist.remove('brightlight'); } else { body.classlist.add('brightlight'); body.classlist.remove('darklight'); } }); } else { console.log('devicelight event not supported'); } specifications specification status comment ambient light sensorthe definition of 'ambient light events' in that specification.
Animation.playbackRate - Web APIs
bottle.addeventlistener("mousedown", shrinkalice, false); bottle.addeventlistener("touchstart", shrinkalice, false); contrariwise, clicking on the cake causes her to "grow," playing alicechange forwards again: var growalice = function() { alicechange.playbackrate = 1; alicechange.play(); } // on tap or click, alice will grow.
... cake.addeventlistener("mousedown", growalice, false); cake.addeventlistener("touchstart", growalice, false); in another example, the red queen's race game, alice and the red queen are constantly slowing down: setinterval( function() { // make sure the playback rate never falls below .4 if (redqueen_alice.playbackrate > .4) { redqueen_alice.playbackrate *= .9; } }, 3000); but clicking or tapping on them causes them to speed up by multiplying their playbackrate: var gofaster = function() { redqueen_alice.playbackrate *= 1.1; } document.addeventlistener("click", gofaster); document.addeventlistener("touchstart", gofaster); specifications specification status comment web animationsthe definition of 'animation.playbackrate' in that specification.
AudioTrackList: change event - Web APIs
bubbles no cancelable no interface event event handler property onchange examples using addeventlistener(): const videoelement = document.queryselector('video'); videoelement.audiotracks.addeventlistener('change', (event) => { console.log(`'${event.type}' event fired`); }); // changing the value of `enabled` will trigger the `change` event const toggletrackbutton = document.queryselector('.toggle-track'); toggletrackbutton.addeventlistener('click', () => { const track = videoelement.audiotracks[0]; track.enabled = !track.enabled; }); using the onchange event handler property: const videoelement = document.querysel...
...ector('video'); videoelement.audiotracks.onchange = (event) => { console.log(`'${event.type}' event fired`); }; // changing the value of `enabled` will trigger the `change` event const toggletrackbutton = document.queryselector('.toggle-track'); toggletrackbutton.addeventlistener('click', () => { const track = videoelement.audiotracks[0]; track.enabled = !track.enabled; }); specifications specification status html living standardthe definition of 'change' in that specification.
Battery Status API - Web APIs
navigator.getbattery().then(function(battery) { function updateallbatteryinfo(){ updatechargeinfo(); updatelevelinfo(); updatecharginginfo(); updatedischarginginfo(); } updateallbatteryinfo(); battery.addeventlistener('chargingchange', function(){ updatechargeinfo(); }); function updatechargeinfo(){ console.log("battery charging?
..."yes" : "no")); } battery.addeventlistener('levelchange', function(){ updatelevelinfo(); }); function updatelevelinfo(){ console.log("battery level: " + battery.level * 100 + "%"); } battery.addeventlistener('chargingtimechange', function(){ updatecharginginfo(); }); function updatecharginginfo(){ console.log("battery charging time: " + battery.chargingtime + " seconds"); } battery.addeventlistener('dischargingtimechange', function(){ updatedischarginginfo(); }); function updatedischarginginfo(){ console.log("battery discharging time: " + battery.dischargingtime + " seconds"); } }); see also the example in the specification.
BeforeUnloadEvent - Web APIs
><text x="201" y="30" font-size="12px" font-family="consolas,monaco,andale mono,monospace" fill="#4d4e53" text-anchor="middle" alignment-baseline="middle">beforeunloadevent</text></a></svg></div> a:hover text { fill: #0095dd; pointer-events: all;} bubbles no cancelable yes target objects defaultview interface event examples window.addeventlistener("beforeunload", function( event ) { event.returnvalue = "\o/"; }); // is equivalent to window.addeventlistener("beforeunload", function( event ) { event.preventdefault(); }); webkit-derived browsers don't follow the spec for the dialog box.
... window.addeventlistener("beforeunload", function (e) { var confirmationmessage = "\o/"; (e || window.event).returnvalue = confirmationmessage; // gecko + ie return confirmationmessage; /* safari, chrome, and other * webkit-derived browsers */ }); specifications specification status comment html living standardthe definition of 'beforeunloadevent' in that specification.
BroadcastChannel: message event - Web APIs
m "fira sans", sans-serif; margin-bottom: 1rem; } textarea { padding: .2rem; } label, br { margin: .5rem 0; } button { vertical-align: top; height: 1.5rem; } const channel = new broadcastchannel('example-channel'); const messagecontrol = document.queryselector('#message'); const broadcastmessagebutton = document.queryselector('#broadcast-message'); broadcastmessagebutton.addeventlistener('click', () => { channel.postmessage(messagecontrol.value); }) receiver 1 <h1>receiver 1</h1> <div id="received"></div> body { border: 1px solid black; padding: .5rem; height: 100px; font-family: "fira sans", sans-serif; } h1 { font: 1.6em "fira sans", sans-serif; margin-bottom: 1rem; } const channel = new broadcastchannel('example-channel'); channel.addeventl...
...istener('message', (event) => { received.textcontent = event.data; }); receiver 2 <h1>receiver 2</h1> <div id="received"></div> body { border: 1px solid black; padding: .5rem; height: 100px; font-family: "fira sans", sans-serif; } h1 { font: 1.6em "fira sans", sans-serif; margin-bottom: 1rem; } const channel = new broadcastchannel('example-channel'); channel.addeventlistener('message', (event) => { received.textcontent = event.data; }); result specifications specification status html living standard living standard ...
Cache - Web APIs
WebAPICache
var cache_version = 1; var current_caches = { font: 'font-cache-v' + cache_version }; self.addeventlistener('activate', function(event) { // delete all caches that aren't named in current_caches.
... console.log('deleting out of date cache:', cachename); return caches.delete(cachename); } }) ); }) ); }); self.addeventlistener('fetch', function(event) { console.log('handling fetch event for', event.request.url); event.respondwith( caches.open(current_caches.font).then(function(cache) { return cache.match(event.request).then(function(response) { if (response) { // if there is an entry in the cache for event.request, then response will be defined // and we can just return it.
CacheStorage - Web APIs
self.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.addall([ '/sw-test/', '/sw-test/index.html', '/sw-test/style.css', '/sw-test/app.js', '/sw-test/image-list.js', '/sw-test/star-wars-logo.jpg', '/sw-test/gallery/bountyhunters.jpg', '/sw-test/gallery/mylittlevader.jpg', ...
... '/sw-test/gallery/snowtroopers.jpg' ]); }) ); }); self.addeventlistener('fetch', function(event) { event.respondwith(caches.match(event.request).then(function(response) { // caches.match() always resolves // but in case of success response will have value if (response !== undefined) { return response; } else { return fetch(event.request).then(function (response) { // response may be used only once // we need to save clone to put one copy in cache // and serve second one let responseclone = response.clone(); caches.open('v1').then(function (cache) { cache.put(event.request, responseclone); }); return response; }).catch(function () { return caches.match('/sw-test/gallery/mylittleva...
CanvasRenderingContext2D.addHitRegion() - Web APIs
html <canvas id="canvas"></canvas> javascript const canvas = document.getelementbyid('canvas'); const ctx = canvas.getcontext('2d'); canvas.addeventlistener('mousemove', function(event) { if(event.region) { alert('ouch, my eye :('); } }); ctx.beginpath(); ctx.arc(100, 100, 75, 0, 2 * math.pi); ctx.linewidth = 5; ctx.stroke(); // eyes ctx.beginpath(); ctx.arc(70, 80, 10, 0, 2 * math.pi); ctx.arc(130, 80, 10, 0, 2 * math.pi); ctx.fill(); ctx.addhitregion({id: "eyes"}); // mouth ctx.beginpath(); ctx.arc(100, 110, 50, 0, math.pi); ctx.stroke()...
...th.pi, false); ctx.stroke();</textarea> var canvas = document.getelementbyid("canvas"); var ctx = canvas.getcontext("2d"); var textarea = document.getelementbyid("code"); var reset = document.getelementbyid("reset"); var edit = document.getelementbyid("edit"); var code = textarea.value; function drawcanvas() { ctx.clearrect(0, 0, canvas.width, canvas.height); eval(textarea.value); } reset.addeventlistener("click", function() { textarea.value = code; drawcanvas(); }); edit.addeventlistener("click", function() { textarea.focus(); }); canvas.addeventlistener("mousemove", function(event){ if(event.region) { alert("ouch, my eye :("); } }); textarea.addeventlistener("input", drawcanvas); window.addeventlistener("load", drawcanvas); specifications canvas hit regions have been remov...
Manipulating video using canvas - Web APIs
var processor; processor.doload = function doload() { this.video = document.getelementbyid('video'); this.c1 = document.getelementbyid('c1'); this.ctx1 = this.c1.getcontext('2d'); this.c2 = document.getelementbyid('c2'); this.ctx2 = this.c2.getcontext('2d'); let self = this; this.video.addeventlistener('play', function() { self.width = self.video.videowidth / 2; self.height = self.video.videoheight / 2; self.timercallback(); }, false); }, this code grabs references to the elements in the xhtml document that are of particular interest, namely the video element and the two canvas elements.
... then addeventlistener() is called to begin watching the video element so that we obtain notification when the user presses the play button on the video.
Using channel messaging - Web APIs
var input = document.getelementbyid('message-input'); var output = document.getelementbyid('message-output'); var button = document.queryselector('button'); var iframe = document.queryselector('iframe'); var channel = new messagechannel(); var port1 = channel.port1; // wait for the iframe to load iframe.addeventlistener("load", onload); function onload() { // listen for button clicks button.addeventlistener('click', onclick); // listen for messages on port1 port1.onmessage = onmessage; // transfer port2 to the iframe iframe.contentwindow.postmessage('init', '*', [channel.port2]); } // post a message on port1 when the button is clicked function onclick(e) { e.preventdefault(); port1.postmessag...
... receiving the port and message in the iframe over in the iframe, we have the following javascript: var list = document.queryselector('ul'); var port2; // listen for the initial port transfer message window.addeventlistener('message', initport); // setup the transferred port function initport(e) { port2 = e.ports[0]; port2.onmessage = onmessage; } // handle messages received on port2 function onmessage(e) { var listitem = document.createelement('li'); listitem.textcontent = e.data; list.appendchild(listitem); port2.postmessage('message received by iframe: "' + e.data + '"'); } when the initial messag...
Client.postMessage() - Web APIs
examples sending a message from a service worker to a client: addeventlistener('fetch', event => { event.waituntil(async function() { // exit early if we don't have access to the client.
... client.postmessage({ msg: "hey i just got a fetch from you!", url: event.request.url }); }()); }); receiving that message: navigator.serviceworker.addeventlistener('message', event => { console.log(event.data.msg, event.data.url); }); specifications specification status comment service workersthe definition of 'postmessage()' in that specification.
DataTransfer.clearData() - Web APIs
</span> <span class="tweaked" id="target">drop zone</span> <div>status: <span id="status">drag to start</span></div> <div>data is: <span id="data">uninitialized</span></div> css span.tweaked { display: inline-block; margin: 1em 0; padding: 1em 2em; } #source { color: blue; border: 1px solid black; } #target { border: 1px solid black; } javascript window.addeventlistener('domcontentloaded', function () { // select html elements var draggable = document.getelementbyid('source'); var dropable = document.getelementbyid('target'); var status = document.getelementbyid('status'); var data = document.getelementbyid('data'); var dropped = false; // register event handlers draggable.addeventlistener('dragstart', dragstarthandler); draggable.addeventlist...
...ener('dragend', dragendhandler); dropable.addeventlistener('dragover', dragoverhandler); dropable.addeventlistener('dragleave', dragleavehandler); dropable.addeventlistener('drop', drophandler); function dragstarthandler (event) { status.innerhtml = 'drag in process'; // change target element's border to signify drag has started event.currenttarget.style.border = '1px dashed blue'; // start by clearing existing clipboards; this will affect all types since we // don't give a specific type.
Using light sensors - Web APIs
10 ~ 50 lux : dim environment 100 ~ 1000 lux : normal > 10000 lux : bright it uses the addeventlistener method of the window object.
... window.addeventlistener("devicelight", function (event) { // read out the lux value var luminosity = event.value; alert(luminosity); }); example: window.addeventlistener('devicelight', function(event) { var bodybg= document.body.style; //event.value is the lux value returned by the sensor on the device if (event.value < 100) { alert('hey, you!
Document: keydown event - Web APIs
to ignore all keydown events that are part of composition, do something like this (229 is a special value set for a keycode relating to an event that has been processed by an ime): eventtarget.addeventlistener("keydown", event => { if (event.iscomposing || event.keycode === 229) { return; } // do something }); examples addeventlistener keydown example this example logs the keyboardevent.code value whenever you press down a key.
...by clicking in it), then try pressing some keys.</p> <p id="log"></p> document.addeventlistener('keydown', logkey); function logkey(e) { log.textcontent += ` ${e.code}`; } onkeydown equivalent document.onkeydown = logkey; specifications specification status ui events working draft ...
Document: keypress event - Web APIs
interface keyboardevent bubbles yes cancelable yes default action varies: keypress event; launch text composition system; blur and focus events; domactivate event; other event examples addeventlistener keypress example this example logs the keyboardevent.code value whenever you press a key.
... <p>press inside this iframe first to focus it, then try pressing keys on the keyboard.</p> <p id="log"></p> const log = document.getelementbyid('log'); document.addeventlistener('keypress', logkey); function logkey(e) { log.textcontent += ` ${e.code}`; } onkeypress equivalent document.onkeypress = logkey; specifications specification status ui events working draft ...
Events and the DOM - Web APIs
eventtarget.addeventlistener // assuming mybutton is a button element mybutton.addeventlistener('click', greet, false) function greet(event){ // print and have a look at the event object // always print arguments in case of overlooking any other arguments console.log('greet:', arguments) alert('hello world') } this is the method you should use in modern web pages.
... more details can be found on the eventtarget.addeventlistener reference page.
EffectTiming.fill - Web APIs
WebAPIEffectTimingfill
document.getelementbyid("animatebutton").addeventlistener("click", event => { document.getelementbyid("box").animate( boxrotationkeyframes, boxrotationtiming ); }, false); the rest of the code is pretty simple: it adds an event listener to the "animate" button so that when it's clicked by the user, the box is animated by calling element.animate() on it, providing the boxrotationkeyframes and boxrotationtiming objects to describe the animati...
... elem.addeventlistener('click', async evt => { const animation = elem.animate( { transform: `translate(${evt.clientx}px, ${evt.clienty}px)` }, { duration: 800, fill: 'forwards' } ); await animation.finished; // commitstyles will record the style up to and including `animation` and // update elem’s specified style with the result.
Element: blur event - Web APIs
cancelable no interface focusevent event handler property onblur sync / async sync composed yes examples simple example html <form id="form"> <input type="text" placeholder="text input"> <input type="password" placeholder="password"> </form> javascript const password = document.queryselector('input[type="password"]'); password.addeventlistener('focus', (event) => { event.target.style.background = 'pink'; }); password.addeventlistener('blur', (event) => { event.target.style.background = ''; }); result event delegation there are two ways of implementing event delegation for this event: by using the focusout event, or by setting the usecapture parameter of addeventlistener() to true.
... html <form id="form"> <input type="text" placeholder="text input"> <input type="password" placeholder="password"> </form> javascript const form = document.getelementbyid('form'); form.addeventlistener('focus', (event) => { event.target.style.background = 'pink'; }, true); form.addeventlistener('blur', (event) => { event.target.style.background = ''; }, true); result specifications specification status comment ui events working draft added info that this event is composed.
Element: compositionend event - Web APIs
bubbles yes cancelable yes interface compositionevent event handler property none examples const inputelement = document.queryselector('input[type="text"]'); inputelement.addeventlistener('compositionend', (event) => { console.log(`generated characters were: ${event.data}`); }); live example html <div class="control"> <label for="name">on macos, click in the textbox below,<br> then type <kbd>option</kbd> + <kbd>`</kbd>, then <kbd>a</kbd>:</label> <input type="text" id="example" name="example"> </div> <div class="event-log"> <label>event log:</label> <textarea readonl...
... .event-log-contents { resize: none; } label, button { display: block; } input[type="text"] { margin: .5rem 0; } kbd { border-radius: 3px; padding: 1px 2px 0; border: 1px solid black; } js const inputelement = document.queryselector('input[type="text"]'); const log = document.queryselector('.event-log-contents'); const clearlog = document.queryselector('.clear-log'); clearlog.addeventlistener('click', () => { log.textcontent = ''; }); function handleevent(event) { log.textcontent = log.textcontent + `${event.type}: ${event.data}\n`; } inputelement.addeventlistener('compositionstart', handleevent); inputelement.addeventlistener('compositionupdate', handleevent); inputelement.addeventlistener('compositionend', handleevent); result specifications specification ...
Element: compositionstart event - Web APIs
bubbles yes cancelable yes interface compositionevent event handler property none examples const inputelement = document.queryselector('input[type="text"]'); inputelement.addeventlistener('compositionstart', (event) => { console.log(`generated characters were: ${event.data}`); }); live example html <div class="control"> <label for="name">on macos, click in the textbox below,<br> then type <kbd>option</kbd> + <kbd>`</kbd>, then <kbd>a</kbd>:</label> <input type="text" id="example" name="example"> </div> <div class="event-log"> <label>event log:</label> <textarea reado...
... .event-log-contents { resize: none; } label, button { display: block; } input[type="text"] { margin: .5rem 0; } kbd { border-radius: 3px; padding: 1px 2px 0; border: 1px solid black; } js const inputelement = document.queryselector('input[type="text"]'); const log = document.queryselector('.event-log-contents'); const clearlog = document.queryselector('.clear-log'); clearlog.addeventlistener('click', () => { log.textcontent = ''; }); function handleevent(event) { log.textcontent = log.textcontent + `${event.type}: ${event.data}\n`; } inputelement.addeventlistener('compositionstart', handleevent); inputelement.addeventlistener('compositionupdate', handleevent); inputelement.addeventlistener('compositionend', handleevent); result specifications specification ...
Element: compositionupdate event - Web APIs
bubbles yes cancelable yes interface compositionevent event handler property none examples const inputelement = document.queryselector('input[type="text"]'); inputelement.addeventlistener('compositionupdate', (event) => { console.log(`generated characters were: ${event.data}`); }); live example html <div class="control"> <label for="name">on macos, click in the textbox below,<br> then type <kbd>option</kbd> + <kbd>`</kbd>, then <kbd>a</kbd>:</label> <input type="text" id="example" name="example"> </div> <div class="event-log"> <label>event log:</label> <textarea read...
... .event-log-contents { resize: none; } label, button { display: block; } input[type="text"] { margin: .5rem 0; } kbd { border-radius: 3px; padding: 1px 2px 0; border: 1px solid black; } js const inputelement = document.queryselector('input[type="text"]'); const log = document.queryselector('.event-log-contents'); const clearlog = document.queryselector('.clear-log'); clearlog.addeventlistener('click', () => { log.textcontent = ''; }); function handleevent(event) { log.textcontent = log.textcontent + `${event.type}: ${event.data}\n`; } inputelement.addeventlistener('compositionstart', handleevent); inputelement.addeventlistener('compositionupdate', handleevent); inputelement.addeventlistener('compositionend', handleevent); result specifications specification ...
Element: focus event - Web APIs
cancelable no interface focusevent event handler property onfocus sync / async sync composed yes examples simple example html <form id="form"> <input type="text" placeholder="text input"> <input type="password" placeholder="password"> </form> javascript const password = document.queryselector('input[type="password"]'); password.addeventlistener('focus', (event) => { event.target.style.background = 'pink'; }); password.addeventlistener('blur', (event) => { event.target.style.background = ''; }); result event delegation there are two ways of implementing event delegation for this event: by using the focusin event, or by setting the usecapture parameter of addeventlistener() to true.
... html <form id="form"> <input type="text" placeholder="text input"> <input type="password" placeholder="password"> </form> javascript const form = document.getelementbyid('form'); form.addeventlistener('focus', (event) => { event.target.style.background = 'pink'; }, true); form.addeventlistener('blur', (event) => { event.target.style.background = ''; }, true); result specifications specification status comment ui events working draft added info that this event is composed.
Element: fullscreenchange event - Web APIs
html <h1>fullscreenchange event example</h1> <div id="fullscreen-div"> <button id="toggle-fullscreen">toggle fullscreen mode</button> </div> javascript document.getelementbyid('fullscreen-div').addeventlistener('fullscreenchange', (event) => { // document.fullscreenelement will point to the element that // is in fullscreen mode if there is one.
... if (document.fullscreenelement) { console.log(`element: ${document.fullscreenelement.id} entered fullscreen mode.`); } else { console.log('leaving full-screen mode.'); } }); document.getelementbyid('toggle-fullscreen').addeventlistener('click', (event) => { if (document.fullscreenelement) { // exitfullscreen is only available on the document object.
Element: keydown event - Web APIs
to ignore all keydown events that are part of composition, do something like this (229 is a special value set for a keycode relating to an event that has been processed by an ime): eventtarget.addeventlistener("keydown", event => { if (event.iscomposing || event.keycode === 229) { return; } // do something }); examples addeventlistener keydown example this example logs the keyboardevent.code value whenever you press down a key inside the <input> element.
... <input placeholder="click here, then press down a key." size="40"> <p id="log"></p> const input = document.queryselector('input'); const log = document.getelementbyid('log'); input.addeventlistener('keydown', logkey); function logkey(e) { log.textcontent += ` ${e.code}`; } onkeydown equivalent input.onkeydown = logkey; specifications specification status ui events working draft ...
Element: keypress event - Web APIs
interface keyboardevent bubbles yes cancelable yes default action varies: keypress event; launch text composition system; blur and focus events; domactivate event; other event examples addeventlistener keypress example this example logs the keyboardevent.code value whenever you press a key after focussing the <input> element.
... <div> <label for="sample">focus the input and type something:</label> <input type="text" name="text" id="sample"> </div> <p id="log"></p> const log = document.getelementbyid('log'); const input = document.queryselector('input'); input.addeventlistener('keypress', logkey); function logkey(e) { log.textcontent += ` ${e.code}`; } onkeypress equivalent input.onkeypress = logkey; specifications specification status ui events working draft ...
Element: keyup event - Web APIs
to ignore all keyup events that are part of composition, do something like this (229 is a special value set for a keycode relating to an event that has been processed by an ime): eventtarget.addeventlistener("keyup", event => { if (event.iscomposing || event.keycode === 229) { return; } // do something }); examples addeventlistener keyup example this example logs the keyboardevent.code value whenever you release a key inside the <input> element.
... <input placeholder="click here, then press and release a key." size="40"> <p id="log"></p> const input = document.queryselector('input'); const log = document.getelementbyid('log'); input.addeventlistener('keyup', logkey); function logkey(e) { log.textcontent += ` ${e.code}`; } onkeyup equivalent input.onkeyup = logkey; specifications specification status ui events working draft ...
Element - Web APIs
WebAPIElement
eventtarget.addeventlistener() registers an event handler to a specific event type on the element.
... events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
Event.eventPhase - Web APIs
WebAPIEventeventPhase
event listeners registered for capture mode when eventtarget.addeventlistener() was called are triggered during this phase.
... removelisteners() { for (let i = 0; i < divs.length; i++) { let d = divs[i] if (d.id != "divinfo") { d.removeeventlistener("click", ondivclick, true) d.removeeventlistener("click", ondivclick, false) } } } function addlisteners() { for (let i = 0; i < divs.length; i++) { let d = divs[i] if (d.id != "divinfo") { if (chcapture.checked) { d.addeventlistener("click", ondivclick, true) } else { d.addeventlistener("click", ondivclick, false) d.onmousemove = function () { clear = true } } } } } function ondivclick(e) { if (clear) { clear() clear = false } if (e.eventphase == 2) e.currenttarget.style.backgroundcolor = 'red'; let level = e.eventphase == 0 ?
Event.preventDefault() - Web APIs
this example demonstrates how to prevent that from happening: javascript document.queryselector("#id-checkbox").addeventlistener("click", function(event) { document.getelementbyid("output-box").innerhtml += "sorry!
...first, listen for keypress events: var mytextbox = document.getelementbyid('my-textbox'); mytextbox.addeventlistener('keypress', checkname, false); the checkname() function, which looks at the pressed key and decides whether to allow it: function checkname(evt) { var charcode = evt.charcode; if (charcode != 0) { if (charcode < 97 || charcode > 122) { evt.preventdefault(); displaywarning( "please use lowercase letters only." + "\n" + "charcode: " + charcode + "\n" ); ...
EventListener - Web APIs
buttonelement.addeventlistener('click', function (event) { alert('element clicked through function!'); }); // for compatibility, a non-function object with a `handleevent` property is // treated just the same as a function itself.
... buttonelement.addeventlistener('click', { handleevent: function (event) { alert('element clicked through handleevent property!'); } }); result see also: addeventlistener specifications specification status comment domthe definition of 'eventlistener' in that specification.
EventSource - Web APIs
const sse = new eventsource('/api/v1/sse'); /* this will listen only for events * similar to the following: * * event: notice * data: useful data * id: someid * */ sse.addeventlistener("notice", function(e) { console.log(e.data) }) /* similarly, this will listen for events * with the field `event: update` */ sse.addeventlistener("update", function(e) { console.log(e.data) }) /* the event "message" is a special case, as it * will capture events without an event field * as well as events that have the specific type * `event: message` it will not...
... */ sse.addeventlistener("message", function(e) { console.log(e.data) }) specifications specification status html living standardthe definition of 'eventsource' in that specification.
EventTarget - Web APIs
methods eventtarget.addeventlistener() registers an event handler of a specific event type on the eventtarget.
... void seteventhandler(domstring type, eventhandler handler) eventhandler geteventhandler(domstring type) example simple implementation of eventtarget var eventtarget = function() { this.listeners = {}; }; eventtarget.prototype.listeners = null; eventtarget.prototype.addeventlistener = function(type, callback) { if (!(type in this.listeners)) { this.listeners[type] = []; } this.listeners[type].push(callback); }; eventtarget.prototype.removeeventlistener = function(type, callback) { if (!(type in this.listeners)) { return; } var stack = this.listeners[type]; for (var i = 0, l = stack.length; i < l; i++) { if (stack[i] === callback){ stack.splic...
FileReader: abort event - Web APIs
iew = document.queryselector('img.preview'); const eventlog = document.queryselector('.event-log-contents'); const reader = new filereader(); function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}: ${event.loaded} bytes transferred\n`; if (event.type === "load") { preview.src = reader.result; } } function addlisteners(reader) { reader.addeventlistener('loadstart', handleevent); reader.addeventlistener('load', handleevent); reader.addeventlistener('loadend', handleevent); reader.addeventlistener('progress', handleevent); reader.addeventlistener('error', handleevent); reader.addeventlistener('abort', handleevent); } function handleselected(e) { eventlog.textcontent = ''; const selectedfile = fileinput.files[0]; i...
...f (selectedfile) { addlisteners(reader); reader.readasdataurl(selectedfile); } reader.abort(); } fileinput.addeventlistener('change', handleselected); result specifications specification status file api working draft ...
FileReader: load event - Web APIs
iew = document.queryselector('img.preview'); const eventlog = document.queryselector('.event-log-contents'); const reader = new filereader(); function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}: ${event.loaded} bytes transferred\n`; if (event.type === "load") { preview.src = reader.result; } } function addlisteners(reader) { reader.addeventlistener('loadstart', handleevent); reader.addeventlistener('load', handleevent); reader.addeventlistener('loadend', handleevent); reader.addeventlistener('progress', handleevent); reader.addeventlistener('error', handleevent); reader.addeventlistener('abort', handleevent); } function handleselected(e) { eventlog.textcontent = ''; const selectedfile = fileinput.files[0]; i...
...f (selectedfile) { addlisteners(reader); reader.readasdataurl(selectedfile); } } fileinput.addeventlistener('change', handleselected); result specifications specification status file api working draft ...
FileReader: loadend event - Web APIs
iew = document.queryselector('img.preview'); const eventlog = document.queryselector('.event-log-contents'); const reader = new filereader(); function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}: ${event.loaded} bytes transferred\n`; if (event.type === "load") { preview.src = reader.result; } } function addlisteners(reader) { reader.addeventlistener('loadstart', handleevent); reader.addeventlistener('load', handleevent); reader.addeventlistener('loadend', handleevent); reader.addeventlistener('progress', handleevent); reader.addeventlistener('error', handleevent); reader.addeventlistener('abort', handleevent); } function handleselected(e) { eventlog.textcontent = ''; const selectedfile = fileinput.files[0]; i...
...f (selectedfile) { addlisteners(reader); reader.readasdataurl(selectedfile); } } fileinput.addeventlistener('change', handleselected); result specifications specification status file api working draft ...
FileReader: loadstart event - Web APIs
iew = document.queryselector('img.preview'); const eventlog = document.queryselector('.event-log-contents'); const reader = new filereader(); function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}: ${event.loaded} bytes transferred\n`; if (event.type === "load") { preview.src = reader.result; } } function addlisteners(reader) { reader.addeventlistener('loadstart', handleevent); reader.addeventlistener('load', handleevent); reader.addeventlistener('loadend', handleevent); reader.addeventlistener('progress', handleevent); reader.addeventlistener('error', handleevent); reader.addeventlistener('abort', handleevent); } function handleselected(e) { eventlog.textcontent = ''; const selectedfile = fileinput.files[0]; i...
...f (selectedfile) { addlisteners(reader); reader.readasdataurl(selectedfile); } } fileinput.addeventlistener('change', handleselected); result specifications specification status file api working draft ...
FileReader: progress event - Web APIs
iew = document.queryselector('img.preview'); const eventlog = document.queryselector('.event-log-contents'); const reader = new filereader(); function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}: ${event.loaded} bytes transferred\n`; if (event.type === "load") { preview.src = reader.result; } } function addlisteners(reader) { reader.addeventlistener('loadstart', handleevent); reader.addeventlistener('load', handleevent); reader.addeventlistener('loadend', handleevent); reader.addeventlistener('progress', handleevent); reader.addeventlistener('error', handleevent); reader.addeventlistener('abort', handleevent); } function handleselected(e) { eventlog.textcontent = ''; const selectedfile = fileinput.files[0]; i...
...f (selectedfile) { addlisteners(reader); reader.readasdataurl(selectedfile); } } fileinput.addeventlistener('change', handleselected); result specifications specification status file api working draft ...
FileReader.readAsDataURL() - Web APIs
example html <input type="file" onchange="previewfile()"><br> <img src="" height="200" alt="image preview..."> javascript function previewfile() { const preview = document.queryselector('img'); const file = document.queryselector('input[type=file]').files[0]; const reader = new filereader(); reader.addeventlistener("load", function () { // convert image file to base64 string preview.src = reader.result; }, false); if (file) { reader.readasdataurl(file); } } live result example reading multiple files html <input id="browse" type="file" onchange="previewfiles()" multiple> <div id="preview"></div> javascript function previewfiles() { var preview = document.queryselector('#preview'...
...); var files = document.queryselector('input[type=file]').files; function readandpreview(file) { // make sure `file.name` matches our extensions criteria if ( /\.(jpe?g|png|gif)$/i.test(file.name) ) { var reader = new filereader(); reader.addeventlistener("load", function () { var image = new image(); image.height = 100; image.title = file.name; image.src = this.result; preview.appendchild( image ); }, false); reader.readasdataurl(file); } } if (files) { [].foreach.call(files, readandpreview); } } note: the filereader() constructor was not supported by internet explorer for versions before 10.
FileReader - Web APIs
as filereader inherits from eventtarget, all those events can also be listened for by using the addeventlistener method.
... events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
GamepadEvent - Web APIs
window.addeventlistener("gamepadconnected", function(e) { console.log("gamepad connected at index %d: %s.
... window.addeventlistener("gamepaddisconnected", function(e) { console.log("gamepad disconnected from index %d: %s", e.gamepad.index, e.gamepad.id); }); specifications specification status comment gamepadthe definition of 'gamepadevent' in that specification.
GeolocationCoordinates.longitude - Web APIs
let button = document.getelementbyid("get-location"); let lattext = document.getelementbyid("latitude"); let longtext = document.getelementbyid("longitude"); button.addeventlistener("click", function() { navigator.geolocation.getcurrentposition(function(position) { let lat = position.coords.latitude; let long = position.coords.longitude; lattext.innertext = lat.tofixed(2); longtext.innertext = long.tofixed(2); }); }); after setting up variables to more conveniently reference the button element and the two elements into which the latitude and logitude wi...
...ll be drawn, the event listener is established by calling addeventlistener() on the <button> element.
GlobalEventHandlers.onpointerdown - Web APIs
you can also use addeventlistener() to add a listener for pointerdown events.
...you could also use addeventlistener(), of course.
HTMLAudioElement - Web APIs
this snippet copies the audio file's duration to a variable: var audioelement = new audio('car_horn.wav'); audioelement.addeventlistener('loadeddata', () => { let duration = audioelement.duration; // the duration variable now holds the duration (in seconds) of the audio clip }) events inherits methods from its parent, htmlmediaelement, and from its ancestor htmlelement.
... listen to events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
HTMLDialogElement: cancel event - Web APIs
nt handler oncancel examples live example html <dialog class="example-dialog"> <button class="close" type="reset">close</button> </dialog> <button class="open-dialog">open dialog</button> <div class="result"></div> css button, div { margin: .5rem; } js const result = document.queryselector('.result'); const dialog = document.queryselector('.example-dialog'); dialog.addeventlistener('cancel', (event) => { result.textcontent = 'dialog was canceled'; }); const opendialog = document.queryselector('.open-dialog'); opendialog.addeventlistener('click', () => { if (typeof dialog.showmodal === 'function') { dialog.showmodal(); result.textcontent = ''; } else { result.textcontent = 'the dialog api is not supported by this browser'; } }); const closebutton ...
...= document.queryselector('.close'); closebutton.addeventlistener('click', () => { dialog.close(); }); result specifications specification status html living standardthe definition of 'cancel' in that specification.
HTMLDialogElement: close event - Web APIs
ler property onclose examples live example html <dialog class="example-dialog"> <button class="close" type="reset">close</button> </dialog> <button class="open-dialog">open dialog</button> <div class="result"></div> css button, div { margin: .5rem; } js const result = document.queryselector('.result'); const dialog = document.queryselector('.example-dialog'); dialog.addeventlistener('close', (event) => { result.textcontent = 'dialog was closed'; }); const opendialog = document.queryselector('.open-dialog'); opendialog.addeventlistener('click', () => { if (typeof dialog.showmodal === 'function') { dialog.showmodal(); result.textcontent = ''; } else { result.textcontent = 'the dialog api is not supported by this browser'; } }); const closebutton =...
... document.queryselector('.close'); closebutton.addeventlistener('click', () => { dialog.close(); }); result specifications specification status html living standardthe definition of 'close' in that specification.
HTMLElement: change event - Web APIs
alue="chocolate">chocolate</option> <option value="sardine">sardine</option> <option value="vanilla">vanilla</option> </select> </label> <div class="result"></div> body { display: grid; grid-template-areas: "select result"; } select { grid-area: select; } .result { grid-area: result; } javascript const selectelement = document.queryselector('.ice-cream'); selectelement.addeventlistener('change', (event) => { const result = document.queryselector('.result'); result.textcontent = `you like ${event.target.value}`; }); result text input element for some elements, including <input type="text">, the change event doesn't fire until the control loses focus.
... html <input placeholder="enter some text" name="name"/> <p id="log"></p> javascript const input = document.queryselector('input'); const log = document.getelementbyid('log'); input.addeventlistener('change', updatevalue); function updatevalue(e) { log.textcontent = e.target.value; } result specifications specification status html living standardthe definition of 'change' in that specification.
HTMLElement: transitioncancel event - Web APIs
bubbles yes cancelable no interface transitionevent event handler property globaleventhandlers.ontransitioncancel examples this code gets an element that has a transition defined and adds a listener to the transitioncancel event: const transition = document.queryselector('.transition'); transition.addeventlistener('transitioncancel', () => { console.log('transition canceled'); }); the same, but using the ontransitioncancel property instead of addeventlistener(): const transition = document.queryselector('.transition'); transition.ontransitioncancel = () => { console.log('transition canceled'); }; live example in the following example, we have a simple <div> element, styled with a transition that ...
... const message = document.queryselector('.message'); const el = document.queryselector('.transition'); el.addeventlistener('transitionrun', function() { message.textcontent = 'transitionrun fired'; }); el.addeventlistener('transitionstart', function() { message.textcontent = 'transitionstart fired'; }); el.addeventlistener('transitioncancel', function() { message.textcontent = 'transitioncancel fired'; }); el.addeventlistener('transitionend', function() { message.textcontent = 'transitionend fired'; }); ...
HTMLElement: transitionend event - Web APIs
examples this code gets an element that has a transition defined and adds a listener to the transitionend event: const transition = document.queryselector('.transition'); transition.addeventlistener('transitionend', () => { console.log('transition ended'); }); the same, but using the ontransitionend: const transition = document.queryselector('.transition'); transition.ontransitionend = () => { console.log('transition ended'); }; live example in the following example, we have a simple <div> element, styled with a transition that includes a delay: <div class="transition">hover over m...
... const message = document.queryselector('.message'); const el = document.queryselector('.transition'); el.addeventlistener('transitionrun', function() { message.textcontent = 'transitionrun fired'; }); el.addeventlistener('transitionstart', function() { message.textcontent = 'transitionstart fired'; }); el.addeventlistener('transitioncancel', function() { message.textcontent = 'transitioncancel fired'; }); el.addeventlistener('transitionend', function() { message.textcontent = 'transitionend fired'; }); ...
HTMLElement: transitionrun event - Web APIs
bubbles yes cancelable no interface transitionevent event handler property ontransitionrun examples this code adds a listener to the transitionrun event: el.addeventlistener('transitionrun', () => { console.log('transition is running but hasn\'t necessarily started transitioning yet'); }); the same, but using the ontransitionrun property instead of addeventlistener(): el.ontransitionrun = () => { console.log('transition started running, and will start transitioning when the transition delay has expired'); }; live example in the following example, we have a simple <div> element, styled with a transition that includ...
... const el = document.queryselector('.transition'); const message = document.queryselector('.message'); el.addeventlistener('transitionrun', function() { message.textcontent = 'transitionrun fired'; }); el.addeventlistener('transitionstart', function() { message.textcontent = 'transitionstart fired'; }); el.addeventlistener('transitionend', function() { message.textcontent = 'transitionend fired'; }); the difference is that: transitionrun fires when the transition is created (i.e.
HTMLElement: transitionstart event - Web APIs
bubbles yes cancelable no interface transitionevent event handler property ontransitionstart examples this code adds a listener to the transitionstart event: element.addeventlistener('transitionstart', () => { console.log('started transitioning'); }); the same, but using the ontransitionstart property instead of addeventlistener(): element.ontransitionrun = () => { console.log('started transitioning'); }; live example in the following example, we have a simple <div> element, styled with a transition that includes a delay: <div class="transition">hover over me</div> <div class="message"></div> .transition { ...
... const transition = document.queryselector('.transition'); const message = document.queryselector('.message'); transition.addeventlistener('transitionrun', function() { message.textcontent = 'transitionrun fired'; }); transition.addeventlistener('transitionstart', function() { message.textcontent = 'transitionstart fired'; }); transition.addeventlistener('transitionend', function() { message.textcontent = 'transitionend fired'; }); the difference is that: transitionrun fires when the transition is created (i.e.
HTMLFormElement: reset event - Web APIs
bubbles yes (although specified as a simple event that doesn't bubble) cancelable yes interface event event handler property globaleventhandlers.onreset examples this example uses eventtarget.addeventlistener() to listen for form resets, and logs the current event.timestamp whenever that occurs.
...time stamp: ${event.timestamp}`; } const form = document.getelementbyid('form'); const log = document.getelementbyid('log'); form.addeventlistener('reset', logreset); result specifications specification status comment html living standardthe definition of 'reset' in that specification.
HTMLFormElement: submit event - Web APIs
examples this example uses eventtarget.addeventlistener() to listen for form submit, and logs the current event.timestamp whenever that occurs, then prevents the default action of submitting the form.
...time stamp: ${event.timestamp}`; event.preventdefault(); } const form = document.getelementbyid('form'); const log = document.getelementbyid('log'); form.addeventlistener('submit', logsubmit); result specifications specification status comment html living standardthe definition of 'submit' in that specification.
HTMLTrackElement: cuechange event - Web APIs
bubbles no cancelable no interface event event handler oncuechange examples on the texttrack you can set up a listener for the cuechange event on a texttrack using the addeventlistener() method: track.addeventlistener('cuechange', function () { let cues = track.activecues; // array of current cues }); or you can just set the oncuechange event handler property: track.oncuechange = function () { let cues = track.activecues; // array of current cues } on the track element the underlying texttrack, indicated by the track property, receives a cuechange event every time th...
... let texttrackelem = document.getelementbyid("texttrack"); texttrackelem.addeventlistener("cuechange", (event) => { let cues = event.target.track.activecues; }); in addition, you can use the oncuechange event handler: let texttrackelem = document.getelementbyid("texttrack"); texttrackelem.oncuechange = (event) => { let cues = event.target.track.activecues; }); specifications specification status html living standardthe definition of 'cuechange' in that specification.
The HTML DOM API - Web APIs
javascript const namefield = document.getelementbyid("username"); const sendbutton = document.getelementbyid("sendbutton") sendbutton.disabled = true; // [note: this is disabled since it causes this article to always load with this example focused and scrolled into view] //namefield.focus(); namefield.addeventlistener("input", event => { const elem = event.target; const valid = elem.value.length != 0; if (valid && sendbutton.disabled) { sendbutton.disabled = false; } else if (!valid && !sendbutton.disabled) { sendbutton.disabled = true; } }); this code uses the document interface's getelementbyid() method to get the dom object representing the <input> elements whose ids are username and sen...
... then addeventlistener() is called to add a handler for the input event to the user name input.
Ajax navigation example - Web APIs
genbmjaejsxgmlwzpeaach5bakkaaaalaaaaaaqabaaaamyclrc/jdksatlqtsckdcecajdii7hcq4emtcpyrcuubjcyrghvtqlaib1yhicnlsrkaaaowaaaaaaaaaaaa=="; ocover.appendchild(oloadingimg); oloadingbox.appendchild(ocover); onpopstate = function (oevent) { bupdateurl = false; opageinfo.title = oevent.state.title; opageinfo.url = oevent.state.url; getpage(); }; window.addeventlistener ?
... addeventlistener("load", init, false) : window.attachevent ?
IDBOpenDBRequest: blocked event - Web APIs
bubbles no cancelable no interface idbversionchangeevent event handler property onblocked examples using addeventlistener(): // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.crea...
...e.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = (event) => { // let's try to open the same database with a higher revision version const req2 = indexeddb.open('todolist', 5); // in this case the onblocked handler will be executed req2.addeventlistener('blocked', () => { console.log('request was blocked'); }); }; using the onblocked property: // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore ...
IDBRequest: success event - Web APIs
bubbles no cancelable no interface event event handler property onsuccess examples this example tries to open a database and listens for the success event using addeventlistener(): // open the database const openrequest = window.indexeddb.open('todolist', 4); openrequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes', 'minu...
...tes', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; openrequest.addeventlistener('success', (event) => { console.log('database opened successfully!'); }); the same example, but using the onsuccess event handler property: // open the database const openrequest = window.indexeddb.open('todolist', 4); openrequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectsto...
IDBTransaction: complete event - Web APIs
bubbles no cancelable no interface event event handler property oncomplete examples using addeventlistener(): // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.onupgradeneeded = event => { const db = event.target.result; db.onerror = () => { console.log('error creating database'); }; // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes', 'minutes', { unique: false }); objectstore.createind...
...nique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = event => { const db = dbopenrequest.result; // open a read/write db transaction, ready for adding the data const transaction = db.transaction(['todolist'], 'readwrite'); // add a listener for `complete` transaction.addeventlistener('complete', event => { console.log('transaction was competed'); }); const objectstore = transaction.objectstore('todolist'); const newitem = { tasktitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'january', year: 2019 }; const objectstorerequest = objectstore.add(newitem); }; using the oncomplete property: // open the database const dbopenrequest = window.indexeddb.open(...
Using IndexedDB - Web APIs
"failure: " + msg : "failure"; $('#msg').html('<span class="action-failure">' + msg + '</span>'); } function resetactionstatus() { console.log("resetactionstatus ..."); $('#msg').empty(); console.log("resetactionstatus done"); } function addeventlisteners() { console.log("addeventlisteners"); $('#register-form-reset').click(function(evt) { resetactionstatus(); }); $('#add-button').click(function(evt) { console.log("add ..."); var title = $('#pub-title').val(); var biblioid = $('#pub-biblioid').val(); if (!title || !biblioid) { displayactionfailure("required field(s) missing"); return...
...'' || isnan(key)) { displayactionfailure("invalid key"); return; } key = number(key); deletepublication(key); } }); $('#clear-store-button').click(function(evt) { clearobjectstore(); }); var search_button = $('#search-list-button'); search_button.click(function(evt) { displaypublist(); }); } opendb(); addeventlisteners(); })(); // immediately-invoked function expression (iife) test the online live demo note: window.indexeddb.open() is asynchronous; the method will finish running long before the success event is fired.
Intersection Observer API - Web APIs
const numsteps = 20.0; let boxelement; let prevratio = 0.0; let increasingcolor = "rgba(40, 40, 190, ratio)"; let decreasingcolor = "rgba(190, 40, 40, ratio)"; // set things up window.addeventlistener("load", (event) => { boxelement = document.queryselector("#box"); createobserver(); }, false); the constants and variables we set up here are: numsteps a constant which indicates how many thresholds we want to have between a visibility ratio of 0.0 and 1.0.
... we call window.addeventlistener() to start listening for the load event; once the page has finished loading, we get a reference to the element with the id "box" using queryselector(), then call the createobserver() method we'll create in a moment to handle building and installing the intersection observer.
KeyboardEvent - Web APIs
example <!doctype html> <html> <head> <script> 'use strict'; document.addeventlistener('keydown', (event) => { const keyname = event.key; if (keyname === 'control') { // do not alert when only control key is pressed.
... alert(`combination of ctrlkey + ${keyname}`); } else { alert(`key pressed ${keyname}`); } }, false); document.addeventlistener('keyup', (event) => { const keyname = event.key; // as the user releases the ctrl key, the key is no longer active, // so event.ctrlkey is false.
MSCandidateWindowShow - Web APIs
syntax event property object.oncandidatewindowshow = handler; addeventlistener method object.addeventlistener("mscandidatewindowshow", handler, usecapture) parameters pevtobj [in] type: ihtmleventobj pointer to an ihtmleventobj interface for the current event.
... example in ie11, developers can detect the opening of the ime candidate window by listening to mscandidatewindowshow event, then call getcandidatewindowclientrect() function to find out where the candidate window is and position the suggestion ui away from it: var context = document.getelementbyid("mysearchbox").msgetinputcontext(); context.addeventlistener("mscandidatewindowshow", candidatewindowshowhandler); function candidatewindowshowhandler(e) { var imerect = context.getcandidatewindowclientrect(); var suggestionrect = document.getelementbyid("mysuggestionlist").getboundingclientrect(); // check if the two rects intersect, and position them away from each other.
msExtendedCode - Web APIs
example var video1 = object.getelementbyid("video1"); video1.addeventlistener('error', function () { var error = video1.error.msextendedcode; //...
... }, false); video.addeventlistener('canplay', function () { video1.play(); }, false); ...
MediaQueryList.addListener() - Web APIs
this is basically an alias for eventtarget.addeventlistener(), for backwards compatibility purposes.
... older browsers should use addlistener instead of addeventlistener since mediaquerylist only inherits from eventtarget in newer browsers.
MediaRecorder: dataavailable event - Web APIs
examples using addeventlistener to listen for dataavailable events: ...
... var chunks = []; mediarecorder.addeventlistener('stop', (event) => { console.log("data available after mediarecorder.stop() called."); var audio = document.createelement('audio'); audio.controls = true; var blob = new blob(chunks, { 'type' : 'audio/ogg; codecs=opus' }); var audiourl = window.url.createobjecturl(blob); audio.src = audiourl; console.log("recorder stopped"); }); mediarecorder.addeventlistener('dataavailable', (event) => { chunks.push(event.data); }); ...
MediaStreamConstraints.audio - Web APIs
idth: 160px; border: 1px solid black; font-size: 16px; text-align: center; padding-top: 2px; padding-bottom: 4px; color: white; background-color: darkgreen; } javascript content let audioelement = document.getelementbyid("audio"); let logelement = document.getelementbyid("log"); function log(msg) { logelement.innerhtml += msg + "<br>"; } document.getelementbyid("startbutton").addeventlistener("click", function() { navigator.mediadevices.getusermedia({ audio: true }).then(stream => audioelement.srcobject = stream) .catch(err => log(err.name + ": " + err.message)); }, false); here we see an event handler for a click event which uses getusermedia() to obtain an audio-only stream with no specific constraints, then attaches the resulting stream to an <audio> element once the s...
...idth: 160px; border: 1px solid black; font-size: 16px; text-align: center; padding-top: 2px; padding-bottom: 4px; color: white; background-color: darkgreen; } javascript content let audioelement = document.getelementbyid("audio"); let logelement = document.getelementbyid("log"); function log(msg) { logelement.innerhtml += msg + "<br>"; } document.getelementbyid("startbutton").addeventlistener("click", function() { navigator.mediadevices.getusermedia({ audio: { samplesize: 8, echocancellation: true } }).then(stream => audioelement.srcobject = stream) .catch(err => log(err.name + ": " + err.message)); }, false); here we see an event handler for a click event which calls getusermedia(), specifying a set of audio constraints requesting that echo cancellation b...
MediaStreamConstraints.video - Web APIs
idth: 160px; border: 1px solid black; font-size: 16px; text-align: center; padding-top: 2px; padding-bottom: 4px; color: white; background-color: darkgreen; } javascript content let videoelement = document.getelementbyid("video"); let logelement = document.getelementbyid("log"); function log(msg) { logelement.innerhtml += msg + "<br>"; } document.getelementbyid("startbutton").addeventlistener("click", function() { navigator.mediadevices.getusermedia({ video: true }).then(stream => videoelement.srcobject = stream) .catch(err => log(err.name + ": " + err.message)); }, false); here we see an event handler for a click event which uses getusermedia() to obtain a video-only stream with no specific constraints, then attaches the resulting stream to a <video> element once the s...
...idth: 160px; border: 1px solid black; font-size: 16px; text-align: center; padding-top: 2px; padding-bottom: 4px; color: white; background-color: darkgreen; } javascript content let videoelement = document.getelementbyid("video"); let logelement = document.getelementbyid("log"); function log(msg) { logelement.innerhtml += msg + "<br>"; } document.getelementbyid("startbutton").addeventlistener("click", function() { navigator.mediadevices.getusermedia({ video: { width: 160, height: 120, framerate: 15 } }).then(stream => videoelement.srcobject = stream) .catch(err => log(err.name + ": " + err.message)); }, false); here we see an event handler for a click event which calls getusermedia(), specifying a set of video constraints that indicate a pr...
Recording a media element - Web APIs
getting an input stream and setting up the recorder now let's look at the most intricate piece of code in this example: our event handler for clicks on the start button: startbutton.addeventlistener("click", function() { navigator.mediadevices.getusermedia({ video: true, audio: true }).then(stream => { preview.srcobject = stream; downloadbutton.href = stream; preview.capturestream = preview.capturestream || preview.mozcapturestream; return new promise(resolve => preview.onplaying = resolve); }).then(() => startrecording(preview.capturestream(), recordingtimems))...
... handling the stop button the last bit of code adds a handler for the click event on the stop button using addeventlistener(): stopbutton.addeventlistener("click", function() { stop(preview.srcobject); }, false); this simply calls the stop() function we covered earlier.
MessageEvent - Web APIs
if the onmessage event is attached using addeventlistener, the port is manually started using its start() method: myworker.port.start(); when the port is started, both scripts post messages to the worker and handle messages sent from it using port.postmessage() and port.onmessage, respectively: first.onchange = function() { myworker.port.postmessage([first.value,second.value]); console.log('message posted to worker'); } second.onchange = functio...
... onconnect = function(e) { var port = e.ports[0]; port.addeventlistener('message', function(e) { var workerresult = 'result: ' + (e.data[0] * e.data[1]); port.postmessage(workerresult); }); port.start(); // required when using addeventlistener.
MessagePort.close() - Web APIs
WebAPIMessagePortclose
example in the following code block, you can see a handlemessage handler function, run when a message is sent back to this document using eventtarget.addeventlistener.
... channel.port1.addeventlistener('message', handlemessage, false); function handlemessage(e) { para.innerhtml = e.data; textinput.value = ''; } channel.port1.start(); you could stop messages being sent at any time using channel.port1.close(); specifications specification status comment html living standardthe definition of 'close()' in that specification.
MessagePort: message event - Web APIs
he ports to a different browsing context, such as another <iframe>, using code like this: const channel = new messagechannel(); const myport = channel.port1; const targetframe = window.top.frames[1]; const targetorigin = 'https://example.org'; const messagecontrol = document.queryselector('#message'); const channelmessagebutton = document.queryselector('#channel-message'); channelmessagebutton.addeventlistener('click', () => { myport.postmessage(messagecontrol.value); }) targetframe.postmessage('init', targetorigin, [channel.port2]); the target can receive the port and start listening for messages on it using code like this: window.addeventlistener('message', (event) => { const myport = event.ports[0]; myport.addeventlistener('message', (event) => { received.textcontent = event.
...this is only needed when using the addeventlistener() method: if the receiver uses onmessage instead, start() is called implicitly: window.addeventlistener('message', (event) => { const myport = event.ports[0]; myport.onmessage = (event) => { received.textcontent = event.data; }; }); specifications specification status html living standard living standard ...
MessagePort.start() - Web APIs
WebAPIMessagePortstart
this method is only needed when using eventtarget.addeventlistener; it is implied when using messagechannel.onmessage.
... example in the following code block, you can see a handlemessage handler function, run when a message is sent back to this document using onmessage: channel.port1.onmessage = handlemessage; function handlemessage(e) { para.innerhtml = e.data; } another option would be to do this using eventtarget.addeventlistener, however, when this method is used, you need to explicitly call start() to begin the flow of messages to this document: channel.port1.addeventlistener('message', handlemessage, false); function handlemessage(e) { para.innerhtml = e.data; textinput.value = ''; } channel.port1.start(); specifications specification status comment html living standardthe definition of ...
MessagePort - Web APIs
start() starts the sending of messages queued on the port (only needed when using eventtarget.addeventlistener; it is implied when using messageport.onmessage.) close() disconnects the port, so it is no longer active.
... var channel = new messagechannel(); var output = document.queryselector('.output'); var iframe = document.queryselector('iframe'); // wait for the iframe to load iframe.addeventlistener("load", onload); function onload() { // listen for messages on port1 channel.port1.onmessage = onmessage; // transfer port2 to the iframe iframe.contentwindow.postmessage('hello from the main page!', '*', [channel.port2]); } // handle messages received on port1 function onmessage(e) { output.innerhtml = e.data; } for a full working example, see our channel messaging basic demo on ...
NavigationPreloadManager - Web APIs
examples feature detecting and enabling navigation preloading addeventlistener('activate', event => { event.waituntil(async function() { if (self.registration.navigationpreload) { // enable navigation preloads!
... addeventlistener('fetch', event => { event.respondwith(async function() { // respond from the cache if we can const cachedresponse = await caches.match(event.request); if (cachedresponse) return cachedresponse; // else, use the preloaded response, if it's there const response = await event.preloadresponse; if (response) return response; // else try the network.
Using Navigation Timing - Web APIs
for example, to measure the perceived loading time for a page: window.addeventlistener("load", function() { let now = new date().gettime(); let loadingtime = now - performance.timing.navigationstart; document.queryselector(".output").innertext = loadingtime + " ms"; }, false); this code, executed when the load event occurs, subtracts from the current time the time at which the navigation whose timing was recorded began (performance.timing.navigationstart), and outp...
...the new code looks like this: window.addeventlistener("load", function() { let now = new date().gettime(); let loadingtime = now - performance.timing.navigationstart; output = "load time: " + loadingtime + " ms<br/>"; output += "navigation type: "; switch(performance.navigation.type) { case performancenavigation.type_navigate: output += "navigation"; break; case performancenavigation.type_reload: output +=...
Navigator.sendBeacon() - Web APIs
window.addeventlistener("unload", function logdata() { var xhr = new xmlhttprequest(); xhr.open("post", "/log", false); // third parameter of `false` means synchronous xhr.send(analyticsdata); }); this is what sendbeacon() replaces.
... window.addeventlistener("unload", function logdata() { navigator.sendbeacon("/log", analyticsdata); }); the beacon sends an http request via the post method, with all relevant cookies available when called.
Notification.close() - Web APIs
at the end of the function, it also calls close() inside a addeventlistener() function to remove the notification when the relevant content has been read on the webpage.
... function spawnnotification(thebody, theicon, thetitle) { var options = { body: thebody, icon: theicon }; var n = new notification(thetitle,options); document.addeventlistener('visibilitychange', function() { if (document.visibilitystate === 'visible') { // the tab has become visible so clear the now-stale notification.
OrientationSensor - Web APIs
const options = { frequency: 60, referenceframe: 'device' }; const sensor = new absoluteorientationsensor(options); sensor.addeventlistener('reading', () => { // model is a three.js object instantiated elsewhere.
... model.quaternion.fromarray(sensor.quaternion).inverse(); }); sensor.addeventlistener('error', error => { if (event.error.name == 'notreadableerror') { console.log("sensor is not available."); } }); sensor.start(); permissions example using orientation sensors requires requsting permissions for multiple device sensors.
PaymentRequest.onshippingaddresschange - Web APIs
syntax paymentrequest.addeventlistener('shippingaddresschange', shippingaddresschangeevent => { ...
...var payment = new paymentrequest(supportedinstruments, details, options); request.addeventlistener('shippingaddresschange', function(evt) { evt.updatewith(new promise(function(resolve) { updatedetails(details, request.shippingaddress, resolve); })); }); payment.show().then(function(paymentresponse) { // processing of paymentresponse exerpted for the same of clarity.
PaymentRequest.onshippingoptionchange - Web APIs
syntax paymentrequest.addeventlistener('shippingoptionchange', shippingoptionchangeevent => { ...
...var request = new paymentrequest(supportedinstruments, details, options); // when user selects a shipping address request.addeventlistener('shippingaddresschange', e => { e.updatewith(((details, addr) => { var shippingoption = { id: '', label: '', amount: { currency: 'usd', value: '0.00' }, selected: true }; // shipping to us is supported if (addr.country === 'us') { shippingoption.id = 'us'; shippingoption.label = 'standard shipping in us'; shippingoption.amount.value = '0...
PaymentRequest: paymentmethodchange event - Web APIs
this code creates a new paymentrequest, adds a handler for the paymentmethodchange event by calling the request's addeventlistener(), then calls show() to present the payment interface to the user.
... const options = { requestshipping: true }; const paymentrequest = new paymentrequest(paymentmethods, detailsforshipping("ground"), options); paymentrequest.addeventlistener("paymentmethodchange", handlepaymentchange, false); paymentrequest.show() .then(response => response.complete("success")) .catch(err => console.log("error handling payment request: " + err)); the event handler function itself, handlepaymentchange(), looks like this: handlepaymentchange = event => { const detailsupdate = {}; if (event.methodname === "https://apple.com/apple-pay") { co...
Proximity Events - Web APIs
this event can be captured at the window object level by using the addeventlistener method (using the deviceproximity or userproximity event name) or by attaching an event handler to the window.ondeviceproximity or window.onuserproximity properties.
... example window.addeventlistener('userproximity', function(event) { if (event.near) { // let's power off the screen navigator.mozpower.screenenabled = false; } else { // otherwise, let's power on the screen navigator.mozpower.screenenabled = true; } }); specifications specification status comment proximity sensorthe definition of 'proximity events' in that specification.
PushEvent.data - Web APIs
WebAPIPushEventdata
self.addeventlistener('push', function(event) { if (!(self.notification && self.notification.permission === 'granted')) { return; } var data = {}; if (event.data) { data = event.data.json(); } var title = data.title || "something has happened"; var message = data.message || "here's something you might want to check out."; var icon = "images/new-notification.png"; var notification = new notification(title, { body: message, tag: 'si...
...mple-push-demo-notification', icon: icon }); notification.addeventlistener('click', function() { if (clients.openwindow) { clients.openwindow('https://example.blog.com/2015/03/04/something-new.html'); } }); }); specifications specification status comment push apithe definition of 'data' in that specification.
PushEvent - Web APIs
WebAPIPushEvent
self.addeventlistener('push', function(event) { if (!(self.notification && self.notification.permission === 'granted')) { return; } var data = {}; if (event.data) { data = event.data.json(); } var title = data.title || "something has happened"; var message = data.message || "here's something you might want to check out."; var icon = "images/new-notification.png"; var notification = new self...
....notification(title, { body: message, tag: 'simple-push-demo-notification', icon: icon }); notification.addeventlistener('click', function() { if (clients.openwindow) { clients.openwindow('https://example.blog.com/2015/03/04/something-new.html'); } }); }); specifications specification status comment push apithe definition of 'pushevent' in that specification.
RTCError - Web APIs
WebAPIRTCError
datachannel.addeventlistener("error", (event) => { let error = event.error; if (error.errordetail === "sdp-syntax-error") { let errline = error.sdplinenumber; let errmessage = error.message; let alertmessage = `a syntax error occurred interpreting line ${errline} of the sdp: ${errmessage}`; showmyalertmessage("data channel error", alertmessage); } else { terminatemyconnection(); } }); if the e...
... the above example uses addeventlistener() to add the handler for error events.
RTCErrorEvent.error - Web APIs
datachannel.addeventlistener("error", (event) => { let error = event.error; if (error.errordetail === "sdp-syntax-error") { let errline = error.sdplinenumber; let errmessage = error.message; let alertmessage = `a syntax error occurred interpreting line ${errline} of the sdp: ${errmessage}`; showmyalertmessage("data channel error", alertmessage); } else { terminatemyconnection(); } }); if the e...
... the above example uses addeventlistener() to add the handler for error events.
RTCPeerConnection: iceconnectionstatechange event - Web APIs
examples an event handler for this event can be added using the rtcpeerconnection.oniceconnectionstatechange property or by using addeventlistener() on the rtcpeerconnection.
... pc.addeventlistener("iceconnectionstatechange", ev => { let stateelem = document.queryselector("#call-state"); stateelem.classname = `${pc.iceconnectionstate}-state`; }, false); this can also be written as: pc.oniceconnectionstatechange = ev => { let stateelem = document.queryselector("#call-state"); stateelem.classname = `${pc.iceconnectionstate}-state`; } specifications specification status comment webrtc 1.0: real-time communication between browsersthe definiti...
RTCPeerConnection: icecandidate event - Web APIs
if you need to perform any special actions when there are no further candidates expected, you're much better off watching the ice gathering state by watching for icegatheringstatechange events: pc.addeventlistener("icegatheringstatechange", ev => { switch(pc.icegatheringstate) { case "new": /* gathering is either just starting or has been reset */ break; case "gathering": /* gathering has begun or is ongoing */ break; case "complete": /* gathering has ended */ break; } }); as you can see in this example, the icegatheringstatechange event lets you know w...
... first, an example using addeventlistener(): pc.addeventlistener("icecandidate", ev => { if (ev.candidate) { sendmessage({ type: "new-ice-candidate", candidate: event.candidate }); } }, false); you can also set the onicecandidate event handler property directly: pc.onicecandidate = ev => { if (ev.candidate) { sendmessage({ type: "new-ice-candidate", candidate: event.candidate }); } }; ...
RTCPeerConnection: negotiationneeded event - Web APIs
examples in this example, we use addeventlistener() to create an event handler for negotiationneeded.
... pc.addeventlistener("negotiationneeded", ev => { pc.createoffer() .then(offer => return pc.setlocaldescription(offer)) .then(() => sendsignalingmessage({ type: "video-offer", sdp: pc.localdescription })) .catch(err => { /* handle error */ ); }, false); after creating the offer, the local end is configured by calling rtcpeerconnection.setlocaldescription(); then a signaling message is created and sent to the remote peer through the signaling server, to share that offer with the other peer.
RTCPeerConnection: track event - Web APIs
pc = new rtcpeerconnection({ iceservers: [ { urls: "turn:fake.turnserver.url", username: "someusername", credential: "somepassword" } ] }); pc.addeventlistener("track", e => { videoelement.srcobject = e.streams[0]; hangupbutton.disabled = false; }, false); the event handler assigns the new track's first stream to an existing <video> element, identified using the variable videoelement.
... you can also assign the event handler function to the ontrack property, rather than use addeventlistener().
RTCTrackEvent - Web APIs
you can add a track event listener to be notified when the new track is available so that you can, for example, attach its media to a <video> element, using either rtcpeerconnection.addeventlistener() or the ontrack event handler property.
... peerconnection.addeventlistener("track", e => { let videoelement = document.getelementbyid("videobox"); videoelement.srcobject = e.streams[0]; }, false); specifications specification status comment webrtc 1.0: real-time communication between browsersthe definition of 'rtctrackevent' in that specification.
RelativeOrientationSensor - Web APIs
const options = { frequency: 60, referenceframe: 'device' }; const sensor = new relativeorientationsensor(options); sensor.addeventlistener('reading', () => { // model is a three.js object instantiated elsewhere.
... model.quaternion.fromarray(sensor.quaternion).inverse(); }); sensor.addeventlistener('error', error => { if (event.error.name == 'notreadableerror') { console.log("sensor is not available."); } }); sensor.start(); permissions example using orientation sensors requires requsting permissions for multiple device sensors.
ResizeObserver - Web APIs
the javascript looks like so: const h1elem = document.queryselector('h1'); const pelem = document.queryselector('p'); const divelem = document.queryselector('body > div'); const slider = document.queryselector('input[type="range"]'); const checkbox = document.queryselector('input[type="checkbox"]'); divelem.style.width = '600px'; slider.addeventlistener('input', () => { divelem.style.width = slider.value + 'px'; }) const resizeobserver = new resizeobserver(entries => { for (const entry of entries) { if (entry.contentboxsize) { h1elem.style.fontsize = math.max(1.5, entry.contentboxsize.inlinesize / 200) + 'rem'; pelem.style.fontsize = math.max(1, entry.contentboxsize.inlinesize / 600) + 'rem'; } else { h1elem.style.
...fontsize = math.max(1.5, entry.contentrect.width / 200) + 'rem'; pelem.style.fontsize = math.max(1, entry.contentrect.width / 600) + 'rem'; } } }); resizeobserver.observe(divelem); checkbox.addeventlistener('change', () => { if (checkbox.checked) { resizeobserver.observe(divelem); } else { resizeobserver.unobserve(divelem); } }); specifications specification status comment resize observerthe definition of 'resizeobserver' in that specification.
SVGAnimationElement: endEvent event - Web APIs
s" repeatcount="indefinite" /> </circle> </svg> <hr> <button>stop animation</button> <ul> </ul> ul { height: 100px; border: 1px solid #ddd; overflow-y: scroll; padding: 10px 30px; } let svgelem = document.queryselector('svg'); let animateelem = document.queryselector('animatemotion'); let list = document.queryselector('ul'); let btn = document.queryselector('button'); animateelem.addeventlistener('beginevent', () => { let listitem = document.createelement('li'); listitem.textcontent = 'beginevent fired'; list.appendchild(listitem); }) animateelem.addeventlistener('endevent', () => { let listitem = document.createelement('li'); listitem.textcontent = 'endevent fired'; list.appendchild(listitem); }) animateelem.addeventlistener('repeatevent', (e) => { let listitem = document...
....createelement('li'); let msg = 'repeatevent fired'; if(e.detail) { msg += '; repeat number: ' + e.detail; } listitem.textcontent = msg; list.appendchild(listitem); }) btn.addeventlistener('click', () => { btn.disabled = true; animateelem.setattribute('repeatcount', '1'); }) event handler property equivalent note that you can also create an event listener for the end event using the onend event handler property: animateelem.onend = () => { console.log('endevent fired'); } specifications specification status comment scalable vector graphics (svg) 2the definition of 'endevent' in that specification.
Screen Wake Lock API - Web APIs
wakelock.addeventlistener('release', () => { // the wake lock has been released statuselem.textcontent = 'wake lock has been released'; }); reacquiring a wake lock the following code reacquires the wake lock should the visibility of the document change and the wake lock is released.
... document.addeventlistener('visibilitychange', () => { if (wakelock !== null && document.visibilitystate === 'visible') { wakelock = await navigator.wakelock.request('screen'); } }); putting it all together you can find the complete code on github here.
Selection.containsNode() - Web APIs
it uses addeventlistener() to check for selectionchange events.
... html <p>can you find the secret word?</p> <p>hmm, where <span id="secret" style="color:transparent">secret</span> could it be?</p> <p id="win" hidden>you found it!</p> javascript const secret = document.getelementbyid('secret'); const win = document.getelementbyid('win'); // listen for selection changes document.addeventlistener('selectionchange', () => { const selection = window.getselection(); const found = selection.containsnode(secret); win.toggleattribute('hidden', !found); }); result specifications specification status comment selection apithe definition of 'selection.containsnode()' in that specification.
Using server-sent events - Web APIs
you can also listen for events with addeventlistener(): evtsource.addeventlistener("ping", function(event) { const newelement = document.createelement("li"); const time = json.parse(event.data).time; newelement.innerhtml = "ping at " + time; eventlist.appendchild(newelement); }); this code is similar, except that it will be called automatically whenever the server sends a message with the event field set to "ping"; it then parses the jso...
...if this is specified, an event will be dispatched on the browser to the listener for the specified event name; the website source code should use addeventlistener() to listen for named events.
ServiceWorker.onstatechange - Web APIs
} serviceworker.addeventlistener('statechange', function(statechangeevent) { ...
... document.queryselector('#kind').textcontent = 'installing'; } else if (registration.waiting) { serviceworker = registration.waiting; document.queryselector('#kind').textcontent = 'waiting'; } else if (registration.active) { serviceworker = registration.active; document.queryselector('#kind').textcontent = 'active'; } if (serviceworker) { logstate(serviceworker.state); serviceworker.addeventlistener('statechange', function(e) { logstate(e.target.state); }); } note that when statechange fires, the service worker's references may have changed.
ServiceWorkerContainer: message event - Web APIs
cancelable no interface messageevent event handler property onmessage examples in this example the service worker get the client's id from a fetch event and then sends it a message using client.postmessage: // in the service worker async function messageclient(clientid) { const client = await clients.get(clientid); client.postmessage('hi client!'); } addeventlistener('fetch', (event) => { messageclient(event.clientid); event.respondwith(() => { // ...
... }); }); the client can receive the message by listening to the message event: // in the page being controlled navigator.serviceworker.addeventlistener('message', (message) => { console.log(message); }); specifications specification status service workersthe definition of 'message' in that specification.
ServiceWorkerContainer.startMessages() - Web APIs
it's possible to start dispatching these messages earlier by calling serviceworkercontainer.startmessages(), for example if you've invoked a message handler using eventtarget.addeventlistener() before the page has finished loading, but want to start processing the messages right away.
... navigator.serviceworker.addeventlistener('message', (e) => { // ...
ServiceWorkerGlobalScope.onpush - Web APIs
} self.addeventlistener('push', function(pushevent) { ...
...the data payload of the push message is available in the event object's data property (pushevent.data, which contains a pushmessagedata object.) self.addeventlistener('push', function(event) { if (!(self.notification && self.notification.permission === 'granted')) { return; } var data = {}; if (event.data) { data = event.data.json(); } var title = data.title || "something has happened"; var message = data.message || "here's something you might want to check out."; var icon = "images/new-notification.png"; var notification = new notification(title, { body: message, tag: 'simple-push-demo-notification', icon: icon }); notification.addeventlist...
ServiceWorkerGlobalScope.onpushsubscriptionchange - Web APIs
} self.addeventlistener('pushsubscriptionchange', function() { ...
... }) example self.addeventlistener('pushsubscriptionchange', function() { // do something, usually resubscribe to push and // send the new subscription details back to the // server via xhr or fetch }); specifications specification status comment push apithe definition of 'onpushsubscriptionchange' in that specification.
SharedWorker - Web APIs
if the onmessage event is attached using addeventlistener, the port is manually started using its start() method: myworker.port.start(); when the port is started, both scripts post messages to the worker and handle messages sent from it using port.postmessage() and port.onmessage, respectively: first.onchange = function() { myworker.port.postmessage([first.value,second.value]); console.log('message posted to worker'); } second.onchange = functio...
... onconnect = function(e) { var port = e.ports[0]; port.addeventlistener('message', function(e) { var workerresult = 'result: ' + (e.data[0] * e.data[1]); port.postmessage(workerresult); }); port.start(); // required when using addeventlistener.
SubtleCrypto.deriveKey() - Web APIs
let encryptbutton = document.queryselector(".ecdh .encrypt-button"); encryptbutton.addeventlistener("click", () => { encrypt(alicessecretkey); }); // bob can use his copy to decrypt the message.
... let decryptbutton = document.queryselector(".ecdh .decrypt-button"); decryptbutton.addeventlistener("click", () => { decrypt(bobssecretkey); }); } pbkdf2 in this example we ask the user for a password, then use it to derive an aes key using pbkdf2, then use the aes key to encrypt a message.
TextTrack: cuechange event - Web APIs
bubbles no cancelable no interface event event handler property globaleventhandlers.oncuechange examples on the texttrack you can set up a listener for the cuechange event on a texttrack using the addeventlistener() method: track.addeventlistener('cuechange', function () { let cues = track.activecues; // array of current cues }); or you can just set the oncuechange event handler property: track.oncuechange = function () { let cues = track.activecues; // array of current cues } on the track element the underlying texttrack, indicated by the track property, receives a cuechange event every time th...
... let texttrackelem = document.getelementbyid("texttrack"); texttrackelem.addeventlistener("cuechange", (event) => { let cues = event.target.track.activecues; }); in addition, you can use the oncuechange event handler: let texttrackelem = document.getelementbyid("texttrack"); texttrackelem.oncuechange = (event) => { let cues = event.target.track.activecues; }); specifications specification status html living standardthe definition of 'cuechange' in that specification.
Using Touch Events - Web APIs
// register touch event handlers someelement.addeventlistener('touchstart', process_touchstart, false); someelement.addeventlistener('touchmove', process_touchmove, false); someelement.addeventlistener('touchcancel', process_touchcancel, false); someelement.addeventlistener('touchend', process_touchend, false); process an event in an event handler, implementing the application's gesture semantics.
... // create touchstart handler someelement.addeventlistener('touchstart', function(ev) { // iterate through the touch points that were activated // for this element and process each event 'target' for (var i=0; i < ev.targettouches.length; i++) { process_target(ev.targettouches[i].target); } }, false); prevent the browser from processing emulated mouse events.
VideoTrackList: change event - Web APIs
bubbles no cancelable no interface event event handler property onchange examples using addeventlistener(): const videoelement = document.queryselector('video'); videoelement.videotracks.addeventlistener('change', (event) => { console.log(`'${event.type}' event fired`); }); // changing the value of `selected` will trigger the `change` event const toggletrackbutton = document.queryselector('.toggle-track'); toggletrackbutton.addeventlistener('click', () => { const track = videoelement.videotracks[0]; track.selected = !track.selected; }); using the onchange event handler property: const videoelement = document.q...
...ueryselector('video'); videoelement.videotracks.onchange = (event) => { console.log(`'${event.type}' event fired`); }; // changing the value of `selected` will trigger the `change` event const toggletrackbutton = document.queryselector('.toggle-track'); toggletrackbutton.addeventlistener('click', () => { const track = videoelement.videotracks[0]; track.selected = !track.selected; }); specifications specification status html living standardthe definition of 'change' in that specification.
WebGLRenderingContext.makeXRCompatible() - Web APIs
javascript the code that handles starting up graphics, switching to vr mode, and so forth looks like this: const outputcanvas = document.queryselector(".output-canvas"); const gl = outputcanvas.getcontext("webgl"); let xrsession = null; let usingxr = false; let currentscene = "scene1"; let glstartbutton; let xrstartbutton; window.addeventlistener("load", (event) => { loadsceneresources(currentscene); glstartbutton.addeventlistener("click", handlestartbuttonclick); xrstartbutton.addeventlistener("click", handlestartbuttonclick); }); outputcanvas.addeventlistener("webglcontextlost", (event) => { /* the context has been lost but can be restored */ event.canceled = true; }); /* when the gl context is reconnected, reload the resou...
...*/ outputcanvas.addeventlistener("webglcontextrestored", (event) => { loadsceneresources(currentscene); }); async function onstartedxrsession(xrsession) { try { await gl.makexrcompatible(); } catch(err) { switch(err) { case aborterror: showsimplemessagebox("unable to transfer the game to your xr headset.", "cancel"); break; case invalidstateerror: showsimplemessagebox("you don't appear to have a compatible xr headset available.", "cancel"); break; default: handlefatalerror(err); break; } xrsession.end(); } } async function handlestartbuttonclick(event) { if (event.target.classlist.contains("use-webxr") && navigator.xr) { try { xrsession = await navigator.xr.requestsession(...
Clearing by clicking - Web APIs
er does not seem to support html5 canvas.</canvas> <button id="color-switcher">press here to switch color</button> body { text-align : center; } canvas { display : block; width : 280px; height : 210px; margin : auto; padding : 0; border : none; background-color : black; } button { display : inline-block; font-size : inherit; margin : auto; padding : 0.6em; } window.addeventlistener("load", function setupwebgl (evt) { "use strict" // cleaning after ourselves.
... var canvas = document.queryselector("#canvas-view"); var button = document.queryselector("#color-switcher"); canvas.addeventlistener("click", switchcolor, false); button.addeventlistener("click", switchcolor, false); // a variable to hold the webglrenderingcontext.
Color masking - Web APIs
height : 210px; margin : auto; padding : 0; border : none; background-color : black; } button { display : inline-block; font-family : serif; font-size : inherit; font-weight : 900; color : white; margin : auto; padding : 0.6em 1.2em; } #red-toggle { background-color : red; } #green-toggle { background-color : green; } #blue-toggle { background-color : blue; } window.addeventlistener("load", function setupanimation (evt) { "use strict" window.removeeventlistener(evt.type, setupanimation, false); var canvas = document.queryselector("canvas"); var gl = canvas.getcontext("webgl") || canvas.getcontext("experimental-webgl"); if (!gl) { document.queryselector("p").innerhtml = "failed to get webgl context." + "your browser or device may not support w...
...ebgl."; return; } gl.viewport(0, 0, gl.drawingbufferwidth, gl.drawingbufferheight); var timer = setinterval(drawanimation, 1000); var mask = [true, true, true]; var redtoggle = document.queryselector("#red-toggle"), greentoggle = document.queryselector("#green-toggle"), bluetoggle = document.queryselector("#blue-toggle"); redtoggle.addeventlistener("click", setcolormask, false); greentoggle.addeventlistener("click", setcolormask, false); bluetoggle.addeventlistener("click", setcolormask, false); function setcolormask(evt) { var index = evt.target === greentoggle && 1 || evt.target === bluetoggle && 2 || 0; mask[index] = !mask[index]; if (mask[index] === true) evt.target.innerhtml="on"; else evt.target.innerhtml="off"; g...
Detect WebGL - Web APIs
window.addeventlistener("load", function() { var paragraph = document.queryselector("p"), button = document.queryselector("button"); // adding click event handler to button.
... button.addeventlistener("click", detectwebglcontext, false); function detectwebglcontext () { // create canvas element.
Scissor animation - Web APIs
animation</button> <canvas>your browser does not seem to support html5 canvas.</canvas> body { text-align : center; } canvas { display : block; width : 280px; height : 210px; margin : auto; padding : 0; border : none; background-color : black; } button { display : block; font-size : inherit; margin : auto; padding : 0.6em; } ;(function(){ "use strict" window.addeventlistener("load", setupanimation, false); // variables to hold the webgl context, and the color and // position of animated squares.
... position = [0, gl.drawingbufferheight]; var button = document.queryselector("button"); var timer; function startanimation(evt) { button.removeeventlistener(evt.type, startanimation, false); button.addeventlistener("click", stopanimation, false); document.queryselector("strong").innerhtml = "stop"; timer = setinterval(drawanimation, 17); drawanimation(); } function stopanimation(evt) { button.removeeventlistener(evt.type, stopanimation, false); button.addeventlistener("click", startanimation, false); document.queryselector("strong").innerhtml = "start"; clearinterval(timer); ...
Using DTMF with WebRTC - Web APIs
initialization when the page loads, we do some basic setup: we fetch references to the dial button and the log output box elements, and we use addeventlistener() to add an event listener to the dial button so that clicking it calls the connectanddial() function to begin the connection process.
... window.addeventlistener("load", function() { logelement = document.queryselector(".log"); dialbutton = document.queryselector("#dial"); dialbutton.addeventlistener("click", connectanddial, false); }); starting the connection process when the dial button is clicked, connectanddial() is called.
Using WebRTC data channels - Web APIs
let datachannel = pc.createdatachannel("myapp channel"); datachannel.addeventlistener("open", (event) => { begintransmission(datachannel); }); manual negotiation to manually negotiate the data channel connection, you need to first create a new rtcdatachannel object using the createdatachannel() method on the rtcpeerconnection, specifying in the options a negotiated property set to true.
... let datachannel = pc.createdatachannel("myapp channel", { negotiated: true }); datachannel.addeventlistener("open", (event) => { begintransmission(datachannel); }); requestremotechannel(datachannel.id); in this code snippet, the channel is created with negotiated set to true, then a function called requestremotechannel() is used to trigger negotiation, to create a remote channel with the same id as the local channel.
WebSocket - Web APIs
WebAPIWebSocket
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
...const socket = new websocket('ws://localhost:8080'); // connection opened socket.addeventlistener('open', function (event) { socket.send('hello server!'); }); // listen for messages socket.addeventlistener('message', function (event) { console.log('message from server ', event.data); }); specifications specification status html living standardthe definition of 'websocket' in that specification.
Movement, orientation, and motion: A WebXR example - Web APIs
window.addeventlistener("load", onload); function onload() { xrbutton = document.queryselector("#enter-xr"); xrbutton.addeventlistener("click", onxrbuttonclick); projectionmatrixout = document.queryselector("#projection-matrix div"); modelmatrixout = document.queryselector("#model-view-matrix div"); cameramatrixout = document.queryselector("#camera-matrix div"); mousematrixout = document.queryselector("#mo...
... function sessionstarted(session) { let refspacetype; xrsession = session; xrbutton.innertext = "exit webxr"; xrsession.addeventlistener("end", sessionended); let canvas = document.queryselector("canvas"); gl = canvas.getcontext("webgl", { xrcompatible: true }); if (allowmouserotation) { canvas.addeventlistener("pointermove", handlepointermove); canvas.addeventlistener("contextmenu", (event) => { event.preventdefault(); }); } if (allowkeyboardmotion) { document.addeventlistener("keydown", handlekeydown); ...
Web Audio API best practices - Web APIs
here is a simple example of creating the context from inside a click event: const button = document.queryselector('button'); button.addeventlistener('click', function() { const audioctx = new audiocontext(); }, false); if however, you create the context outside of a user gesture, its state will be set to suspended and it will need to be started after user interaction.
... const audioctx = new audiocontext(); const button = document.queryselector('button'); button.addeventlistener('click', function() { // check if context is in suspended state (autoplay policy) if (audioctx.state === 'suspended') { audioctx.resume(); } }, false); you might instead be working with an offlineaudiocontext, in which case you can resume the suspended audio context with the startrendering() method.
Controlling multiple parameters with ConstantSourceNode - Web APIs
function setup() { context = new (window.audiocontext || window.webkitaudiocontext)(); playbutton = document.queryselector("#playbutton"); volumecontrol = document.queryselector("#volumecontrol"); playbutton.addeventlistener("click", toggleplay, false); volumecontrol.addeventlistener("input", changevolume, false); gainnode1 = context.creategain(); gainnode1.gain.value = 0.5; gainnode2 = context.creategain(); gainnode3 = context.creategain(); gainnode2.gain.value = gainnode1.gain.value; gainnode3.gain.value = gainnode1.gain.value; volumecontrol.value = gainnode1.gain.value; constantnode = context.
...createconstantsource(); constantnode.connect(gainnode2.gain); constantnode.connect(gainnode3.gain); constantnode.start(); gainnode1.connect(context.destination); gainnode2.connect(context.destination); gainnode3.connect(context.destination); } window.addeventlistener("load", setup, false); first, we get access to the window's audiocontext, stashing the reference in context.
Using IIR filters - Web APIs
the play button html looks like this: <button class="button-play" role="switch" data-playing="false" aria-pressed="false">play</button> and the click event listener starts like so: playbutton.addeventlistener('click', function() { if (this.dataset.playing === 'false') { srcnode = playsourcenode(audioctx, sample); ...
...first, the html: <button class="button-filter" role="switch" data-filteron="false" aria-pressed="false" aria-describedby="label" disabled></button> the filter button's click handler then connects the iirfilter up to the graph, between the source and the detination: filterbutton.addeventlistener('click', function() { if (this.dataset.filteron === 'false') { srcnode.disconnect(audioctx.destination); srcnode.connect(iirfilter).connect(audioctx.destination); ...
Window: blur event - Web APIs
WebAPIWindowblur event
it uses addeventlistener() to monitor focus and blur events.
...click outside the document to lose focus.'; } const log = document.getelementbyid('log'); window.addeventlistener('blur', pause); window.addeventlistener('focus', play); result specifications specification status comment ui events working draft added info that this event is composed.
Window: focus event - Web APIs
it uses addeventlistener() to monitor focus and blur events.
...click outside the document to lose focus.'; } const log = document.getelementbyid('log'); window.addeventlistener('blur', pause); window.addeventlistener('focus', play); result specifications specification status comment ui events working draft added info that this event is composed.
Window: load event - Web APIs
WebAPIWindowload event
bubbles no cancelable no interface event event handler property onload examples log a message when the page is fully loaded: window.addeventlistener('load', (event) => { console.log('page is fully loaded'); }); the same, but using the onload event handler property: window.onload = (event) => { console.log('page is fully loaded'); }; live example html <div class="controls"> <button id="reload" type="button">reload</button> </div> <div class="event-log"> <label>event log:</label> <textarea readonly class="event-log-contents" ro...
...plate-areas: "control log"; } .controls { grid-area: control; display: flex; align-items: center; justify-content: center; } .event-log { grid-area: log; } .event-log-contents { resize: none; } label, button { display: block; } #reload { height: 2rem; } js const log = document.queryselector('.event-log-contents'); const reload = document.queryselector('#reload'); reload.addeventlistener('click', () => { log.textcontent =''; window.settimeout(() => { window.location.reload(true); }, 200); }); window.addeventlistener('load', (event) => { log.textcontent = log.textcontent + 'load\n'; }); document.addeventlistener('readystatechange', (event) => { log.textcontent = log.textcontent + `readystate: ${document.readystate}\n`; }); document.addeventlistener('domconte...
Window.onbeforeinstallprompt - Web APIs
syntax window.addeventlistener("beforeinstallprompt", function(event) { ...
... window.addeventlistener("beforeinstallprompt", function(beforeinstallpromptevent) { beforeinstallpromptevent.preventdefault(); // prevents immediate prompt display // shows prompt after a user clicks an "install" button installbutton.addeventlistener("click", function(mouseevent) { // you should not use the mouseevent here, obviously beforeinstallpromptevent.prompt(); }); installbutton.hidden = false; // make button operable }); ...
Window: resize event - Web APIs
it is still possible to set onresize attributes or use addeventlistener() to set a handler on any element.
...>resize</code> event.</p> <p>window height: <span id="height"></span></p> <p>window width: <span id="width"></span></p> const heightoutput = document.queryselector('#height'); const widthoutput = document.queryselector('#width'); function reportwindowsize() { heightoutput.textcontent = window.innerheight; widthoutput.textcontent = window.innerwidth; } window.onresize = reportwindowsize; addeventlistener equivalent you could set up the event handler using the addeventlistener() method: window.addeventlistener('resize', reportwindowsize); specifications specification status document object model (dom) level 3 events specificationthe definition of 'resize' in that specification.
Window: unhandledrejection event - Web APIs
window.addeventlistener("unhandledrejection", event => { console.warn(`unhandled promise rejection: ${event.reason}`); }); you can also use the onunhandledrejection event handler property to set up the event listener: window.onunhandledrejection = event => { console.warn(`unhandled promise rejection: ${event.reason}`); }; preventing default handling many environments (such as node.js) report unhandled promise ...
... window.addeventlistener('unhandledrejection', function (event) { // ...your code here to handle the unhandled rejection...
Window: unload event - Web APIs
examples <!doctype html> <html> <head> <title>parent frame</title> <script> window.addeventlistener('beforeunload', function(event) { console.log('i am the 1st one.'); }); window.addeventlistener('unload', function(event) { console.log('i am the 3rd one.'); }); </script> </head> <body> <iframe src="child-frame.html"></iframe> </body> </html> below, the content of child-frame.html: <!doctype html> <html> <head> <title>child frame</title> ...
... <script> window.addeventlistener('beforeunload', function(event) { console.log('i am the 2nd one.'); }); window.addeventlistener('unload', function(event) { console.log('i am the 4th and last one…'); }); </script> </head> <body> ☻ </body> </html> when the parent frame is unloaded, events will be fired in the order described by the console.log() messages.
Window - Web APIs
WebAPIWindow
methods implemented from elsewhere eventtarget.addeventlistener() register an event handler to a specific event type on the window.
... events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
WindowEventHandlers.onunload - Web APIs
syntax window.addeventlistener("unload", function(event) { ...
...}; typically, it is better to use window.addeventlistener() and the unload event, instead of onunload.
Synchronous and asynchronous requests - Web APIs
window.addeventlistener('unload', logdata, false); function logdata() { var client = new xmlhttprequest(); client.open("post", "/log", false); // third parameter indicates sync xhr.
... window.addeventlistener('unload', logdata, false); function logdata() { navigator.sendbeacon("/log", analyticsdata); } ...
XMLHttpRequest: abort event - Web APIs
} js const xhrbuttonsuccess = document.queryselector('.xhr.success'); const xhrbuttonerror = document.queryselector('.xhr.error'); const xhrbuttonabort = document.queryselector('.xhr.abort'); const log = document.queryselector('.event-log'); function handleevent(e) { log.textcontent = log.textcontent + `${e.type}: ${e.loaded} bytes transferred\n`; } function addlisteners(xhr) { xhr.addeventlistener('loadstart', handleevent); xhr.addeventlistener('load', handleevent); xhr.addeventlistener('loadend', handleevent); xhr.addeventlistener('progress', handleevent); xhr.addeventlistener('error', handleevent); xhr.addeventlistener('abort', handleevent); } function runxhr(url) { log.textcontent = ''; const xhr = new xmlhttprequest(); addlisteners(xhr); xhr.open("...
...get", url); xhr.send(); return xhr; } xhrbuttonsuccess.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg'); }); xhrbuttonerror.addeventlistener('click', () => { runxhr('https://somewhere.org/i-dont-exist'); }); xhrbuttonabort.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg').abort(); }); result specifications specification status comment xmlhttprequest living standard ...
XMLHttpRequest: error event - Web APIs
} js const xhrbuttonsuccess = document.queryselector('.xhr.success'); const xhrbuttonerror = document.queryselector('.xhr.error'); const xhrbuttonabort = document.queryselector('.xhr.abort'); const log = document.queryselector('.event-log'); function handleevent(e) { log.textcontent = log.textcontent + `${e.type}: ${e.loaded} bytes transferred\n`; } function addlisteners(xhr) { xhr.addeventlistener('loadstart', handleevent); xhr.addeventlistener('load', handleevent); xhr.addeventlistener('loadend', handleevent); xhr.addeventlistener('progress', handleevent); xhr.addeventlistener('error', handleevent); xhr.addeventlistener('abort', handleevent); } function runxhr(url) { log.textcontent = ''; const xhr = new xmlhttprequest(); addlisteners(xhr); xhr.open("...
...get", url); xhr.send(); return xhr; } xhrbuttonsuccess.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg'); }); xhrbuttonerror.addeventlistener('click', () => { runxhr('https://somewhere.org/i-dont-exist'); }); xhrbuttonabort.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg').abort(); }); result specifications specification status comment xmlhttprequest living standard ...
XMLHttpRequest: load event - Web APIs
} js const xhrbuttonsuccess = document.queryselector('.xhr.success'); const xhrbuttonerror = document.queryselector('.xhr.error'); const xhrbuttonabort = document.queryselector('.xhr.abort'); const log = document.queryselector('.event-log'); function handleevent(e) { log.textcontent = log.textcontent + `${e.type}: ${e.loaded} bytes transferred\n`; } function addlisteners(xhr) { xhr.addeventlistener('loadstart', handleevent); xhr.addeventlistener('load', handleevent); xhr.addeventlistener('loadend', handleevent); xhr.addeventlistener('progress', handleevent); xhr.addeventlistener('error', handleevent); xhr.addeventlistener('abort', handleevent); } function runxhr(url) { log.textcontent = ''; const xhr = new xmlhttprequest(); addlisteners(xhr); xhr.open("...
...get", url); xhr.send(); return xhr; } xhrbuttonsuccess.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg'); }); xhrbuttonerror.addeventlistener('click', () => { runxhr('https://somewhere.org/i-dont-exist'); }); xhrbuttonabort.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg').abort(); }); result specifications specification status comment xmlhttprequest living standard ...
XMLHttpRequest: loadend event - Web APIs
} js const xhrbuttonsuccess = document.queryselector('.xhr.success'); const xhrbuttonerror = document.queryselector('.xhr.error'); const xhrbuttonabort = document.queryselector('.xhr.abort'); const log = document.queryselector('.event-log'); function handleevent(e) { log.textcontent = log.textcontent + `${e.type}: ${e.loaded} bytes transferred\n`; } function addlisteners(xhr) { xhr.addeventlistener('loadstart', handleevent); xhr.addeventlistener('load', handleevent); xhr.addeventlistener('loadend', handleevent); xhr.addeventlistener('progress', handleevent); xhr.addeventlistener('error', handleevent); xhr.addeventlistener('abort', handleevent); } function runxhr(url) { log.textcontent = ''; const xhr = new xmlhttprequest(); addlisteners(xhr); xhr.open("...
...get", url); xhr.send(); return xhr; } xhrbuttonsuccess.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg'); }); xhrbuttonerror.addeventlistener('click', () => { runxhr('https://somewhere.org/i-dont-exist'); }); xhrbuttonabort.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg').abort(); }); result specifications specification status comment xmlhttprequest living standard ...
XMLHttpRequest: loadstart event - Web APIs
} js const xhrbuttonsuccess = document.queryselector('.xhr.success'); const xhrbuttonerror = document.queryselector('.xhr.error'); const xhrbuttonabort = document.queryselector('.xhr.abort'); const log = document.queryselector('.event-log'); function handleevent(e) { log.textcontent = log.textcontent + `${e.type}: ${e.loaded} bytes transferred\n`; } function addlisteners(xhr) { xhr.addeventlistener('loadstart', handleevent); xhr.addeventlistener('load', handleevent); xhr.addeventlistener('loadend', handleevent); xhr.addeventlistener('progress', handleevent); xhr.addeventlistener('error', handleevent); xhr.addeventlistener('abort', handleevent); } function runxhr(url) { log.textcontent = ''; const xhr = new xmlhttprequest(); addlisteners(xhr); xhr.open("...
...get", url); xhr.send(); return xhr; } xhrbuttonsuccess.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg'); }); xhrbuttonerror.addeventlistener('click', () => { runxhr('https://somewhere.org/i-dont-exist'); }); xhrbuttonabort.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg').abort(); }); result specifications specification status comment xmlhttprequest living standard ...
XMLHttpRequest: progress event - Web APIs
} js const xhrbuttonsuccess = document.queryselector('.xhr.success'); const xhrbuttonerror = document.queryselector('.xhr.error'); const xhrbuttonabort = document.queryselector('.xhr.abort'); const log = document.queryselector('.event-log'); function handleevent(e) { log.textcontent = log.textcontent + `${e.type}: ${e.loaded} bytes transferred\n`; } function addlisteners(xhr) { xhr.addeventlistener('loadstart', handleevent); xhr.addeventlistener('load', handleevent); xhr.addeventlistener('loadend', handleevent); xhr.addeventlistener('progress', handleevent); xhr.addeventlistener('error', handleevent); xhr.addeventlistener('abort', handleevent); } function runxhr(url) { log.textcontent = ''; const xhr = new xmlhttprequest(); addlisteners(xhr); xhr.open("...
...get", url); xhr.send(); return xhr; } xhrbuttonsuccess.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg'); }); xhrbuttonerror.addeventlistener('click', () => { runxhr('https://somewhere.org/i-dont-exist'); }); xhrbuttonabort.addeventlistener('click', () => { runxhr('https://mdn.mozillademos.org/files/16553/dgszyjnxcaipwzy.jpg').abort(); }); result specifications specification status comment xmlhttprequest living standard ...
XRSession: select event - Web APIs
examples the following example uses addeventlistener() to set up a handler for the select event.
... xrsession.addeventlistener("select", event => { if (event.inputsource.targetraymode == "tracked-pointer") { let targetraypose = event.frame.getpose(event.inputsource.targetrayspace, myrefspace); if (targetraypose) { myhandleselectwithray(targetraypose.transform); } } }); you can of course also set up a handler for select events by setting the xrsession object's onselect event handler property to a function that handles the event: xrsession.onselect = event => { if (event.inputsource.targetraymode == "tracked-pointer") { let targetraypose = event.frame.getpose(event.inputsource.targetra...
XRSession: selectend event - Web APIs
examples the following example uses addeventlistener() to establish handlers for the selection events: selectstart, selectend, and select.
... xrsession.addeventlistener("selectstart", onselectionevent); xrsession.addeventlistener("select", onselectionevent); xrsession.addeventlistener("selectend", onselectionevent); function onselectionevent(event) { let source = event.inputsource; let targetobj = null; if (source.targetraymode != "tracked-pointer") { return; } let targetraypose = event.frame.getpose(source.targetrayspace, myrefspace); if (!ta...
XRSession: selectstart event - Web APIs
examples the following example uses addeventlistener() to establish handlers for the selection events: selectstart, selectend, and select.
... xrsession.addeventlistener("selectstart", onselectionevent); xrsession.addeventlistener("select", onselectionevent); xrsession.addeventlistener("selectend", onselectionevent); function onselectionevent(event) { let source = event.inputsource; let targetobj = null; if (source.targetraymode != "tracked-pointer") { return; } let targetraypose = event.frame.getpose(source.targetrayspace, myrefspace); if (!ta...
XRSession: squeeze event - Web APIs
examples the following example uses addeventlistener() to set up a handler for the squeeze event.
... xrsession.addeventlistener("squeeze", event => { if (event.inputsource.targetraymode == "tracked-pointer") { let targetraypose = event.frame.getpose(event.inputsource.targetrayspace, myrefspace); if (targetraypose) { myhandlesqueezewithray(targetraypose.transform); } } }); you can of course also set up a handler for squeeze events by setting the xrsession object's onsqu...
XRSession: squeezeend event - Web APIs
examples the following example uses addeventlistener() to establish handlers for the squeezeion events: squeezestart, squeezeend, and squeeze.
... xrsession.addeventlistener("squeezestart", onsqueezeevent); xrsession.addeventlistener("squeeze", onsqueezeevent); xrsession.addeventlistener("squeezeend", onsqueezeevent); function onsqueezeevent(event) { let source = event.inputsource; let targetobj = null; if (source.targetraymode != "tracked-pointer") { return; } let targetraypose = event.frame.getpose(source.targetrayspace, myrefspace); if (!targetr...
XRSession: squeezestart event - Web APIs
examples the following example uses addeventlistener() to establish handlers for the squeezeion events: squeezestart, squeezeend, and squeeze.
... xrsession.addeventlistener("squeezestart", onsqueezeevent); xrsession.addeventlistener("squeeze", onsqueezeevent); xrsession.addeventlistener("squeezeend", onsqueezeevent); function onsqueezeevent(event) { let source = event.inputsource; let targetobj = null; if (source.targetraymode != "tracked-pointer") { return; } let targetraypose = event.frame.getpose(source.targetrayspace, myrefspace); if (!targetr...
XRSystem: requestSession() - Web APIs
navigator.xr.requestsession("immersive-vr") .then((xrsession) => { xrsession.addeventlistener('end', onxrsessionended); // do necessary session setup here.
... if (navigator.xr) { navigator.xr.issessionsupported('immersive-vr') .then((issupported) => { if (issupported) { immersivebutton.addeventlistener('click', onbuttonclicked); immersivebutton.innerhtml = 'enter xr'; immersivebutton.disabled = false; } else { console.log("webxr doesn't support immersive-vr mode!"); } }); } else { console.log("webxr is not available!"); } function onbuttonclicked() { if (!xrsession) { navigator.xr.requestsession('immersive-vr') .then((session) => { xrsession = sess...
msthumbnailclick - Web APIs
syntax event property object.onmsthumbnailclick = handler; addeventlistener method object.addeventlistener("msthumbnailclick", handler, usecapture) general info synchronous no bubbles no cancelable no note the onmsthumbnailclick event is available only to documents that are launched from a pinned site shortcut.
... example function thumbnailclickhandler(evt) { alert ("clicked button: " + evt.buttonid); } document.addeventlistener('msthumbnailclick', thumbnailclickhandler); example 2 // adds an overlay icon on your app pinned to the taskbar window.external.mssitemodeseticonoverlay(iconuri, tooltip); // removes an overlay icon window.external.mssitemodecleariconoverlay(); // pinned icons on your taskbar can be instructed to trigger specific events on your site from the taskbar // add an event handlerdocument.addeventlistener('msthumbnailclick', onbuttonclicked, false); // add the buttons var btnplay = window.external.mssitemodeaddthumbbarbutton(iconuri, tooltip); // refresh the taskbar window.ext...
ARIA: grid role - Accessibility
data-row="' + newrow + '"][data-col="' + newcol + '"]'); if (tgt && (tgt.getattribute('role')==='gridcell') ) { array.prototype.foreach.call(document.queryselectorall('[role=gridcell]'), function(el, i){ el.setattribute('tabindex', '-1'); }); tgt.setattribute('tabindex', '0'); tgt.focus(); return true; } else { return false; } } document.queryselector('table').addeventlistener("keydown", function(event) { switch (event.key) { case "arrowright": moveto(parseint(event.target.dataset.row, 10), parseint(event.target.dataset.col, 10) + 1); break; case "arrowleft": moveto(parseint(event.target.dataset.row, 10), parseint(event.target.dataset.col, 10) - 1); break; case "arrowdown": moveto(parseint(event.target.dataset.row, 10) + 1, p...
...data-row="' + newrow + '"][data-col="' + newcol + '"]'); if (tgt && (tgt.getattribute('role')==='gridcell') ) { array.prototype.foreach.call(document.queryselectorall('[role=gridcell]'), function(el, i){ el.setattribute('tabindex', '-1'); }); tgt.setattribute('tabindex', '0'); tgt.focus(); return true; } else { return false; } } document.queryselector('table').addeventlistener("keydown", function(event) { switch (event.key) { case "arrowright": moveto(parseint(event.target.dataset.row, 10), parseint(event.target.dataset.col, 10) + 1); break; case "arrowleft": moveto(parseint(event.target.dataset.row, 10), parseint(event.target.dataset.col, 10) - 1); break; case "arrowdown": moveto(parseint(event.target.dataset.row, 10) + 1, p...
Coordinate systems - CSS: Cascading Style Sheets
function update(e) { setcoords(e, "offset"); setcoords(e, "client"); setcoords(e, "page"); setcoords(e, "screen"); } inner.addeventlistener("mouseenter", update, false); inner.addeventlistener("mousemove", update, false); inner.addeventlistener("mouseleave", update, false); the event handler is in the update() method.
... our main code sets up the event handlers on the inner box by calling addeventlistener() for each of the types mouseenter, mousemove, and mouseleave.
CSS Animations tips and tricks - CSS: Cascading Style Sheets
of course, we also need to add an event handler to our "run" button so it'll actually do something: document.queryselector(".runbutton").addeventlistener("click", play, false); result stopping an animation simply removing the animation-name applied to an element will make it jump or cut to its next state.
...animation-iteration-count: infinite; } .stopped { animation-name: none; } @keyframes slidein { 0% { margin-left: 0%; } 50% { margin-left: 50%; } 100% { margin-left: 0%; } } <h1 id="watchme">click me to stop</h1> let watchme = document.getelementbyid('watchme') watchme.classname = 'slidein' const listener = (e) => { watchme.classname = 'slidein stopped' } watchme.addeventlistener('click', () => watchme.addeventlistener('animationiteration', listener, false) ) demo https://jsfiddle.net/morenoh149/5ty5a4oy/ ...
Using CSS transitions - CSS: Cascading Style Sheets
<p>click anywhere to move the ball</p> <div id="foo"></div> using javascript you can make the effect of moving the ball to a certain position happen: var f = document.getelementbyid('foo'); document.addeventlistener('click', function(ev){ f.style.transform = 'translatey('+(ev.clienty-25)+'px)'; f.style.transform += 'translatex('+(ev.clientx-25)+'px)'; },false); with css you can make it smooth without any extra effort.
... as usual, you can use the addeventlistener() method to monitor for this event: el.addeventlistener("transitionend", updatetransition, true); you detect the beginning of a transition using transitionrun (fires before any delay) and transitionstart (fires after any delay), in the same kind of fashion: el.addeventlistener("transitionrun", signalstart, true); el.addeventlistener("transitionstart", signalstart, true); note: the transition...
animation - CSS: Cascading Style Sheets
WebCSSanimation
eft; flex: none; } .overlay { padding: .5em; } @keyframes slidein { from { transform: scalex(0); } to { transform: scalex(1); } } .a1 { animation: 3s ease-in 1s 2 reverse both paused slidein; } .a2 { animation: 3s linear 1s slidein; } .a3 { animation: 3s slidein; } .animation { background: #3f87a6; width: 100%; height: calc(100% - 1.5em); transform-origin: left center; } window.addeventlistener('load', function () { var animation = array.from(document.queryselectorall('.animation')); var button = array.from(document.queryselectorall('button')); function togglebutton (btn, type) { btn.classlist.remove('play', 'pause', 'restart'); btn.classlist.add(type); btn.title = type.touppercase(type); } function playpause (i) { var btn = button[i]; var anim = anim...
...'play' : 'pause'); anim.style.animationplaystate = ''; anim.classlist.add('a' + (i + 1)); }, 100) } } animation.foreach(function (node, index) { node.addeventlistener('animationstart', function () { togglebutton(button[index], 'pause'); }); node.addeventlistener('animationend', function () { togglebutton(button[index], 'restart'); }); }); button.foreach(function (btn, index) { btn.addeventlistener('click', function () { playpause(index); }); }); }) a description of which properties are animatable is available; it's worth noting that this...
place-content - CSS: Cascading Style Sheets
"safe">safe</option> <option value="unsafe">unsafe</option> </select><code>;</code> var update = function () { document.getelementbyid("container").style.placecontent = document.getelementbyid("aligncontentalignment").value + " " + document.getelementbyid("justifycontentalignment").value; } var aligncontentalignment = document.getelementbyid("aligncontentalignment"); aligncontentalignment.addeventlistener("change", update); var justifycontentalignment = document.getelementbyid("justifycontentalignment"); justifycontentalignment.addeventlistener("change", update); var writingm = document.getelementbyid("writingmode"); writingm.addeventlistener("change", function (evt) { document.getelementbyid("container").style.writingmode = evt.target.value; }); var direction = document.getelementbyid("dire...
...ction"); direction.addeventlistener("change", function (evt) { document.getelementbyid("container").style.direction = evt.target.value; }); css #container { display: flex; height:240px; width: 240px; flex-wrap: wrap; background-color: #8c8c8c; writing-mode: horizontal-tb; /* can be changed in the live sample */ direction: ltr; /* can be changed in the live sample */ place-content: flex-end center; /* can be changed in the live sample */ } div > div { border: 2px solid #8c8c8c; width: 50px; background-color: #a0c8ff; } .small { font-size: 12px; height: 40px; } .large { font-size: 14px; height: 50px; } result specifications specification status comment css box alignment module level 3the definition of 'place content' in that specifica...
Adding captions and subtitles to HTML5 video - Developer guides
l) { var listitem = document.createelement('li'); var button = listitem.appendchild(document.createelement('button')); button.setattribute('id', id); button.classname = 'subtitles-button'; if (lang.length > 0) button.setattribute('lang', lang); button.value = label; button.setattribute('data-state', 'inactive'); button.appendchild(document.createtextnode(label)); button.addeventlistener('click', function(e) { // set all buttons to inactive subtitlemenubuttons.map(function(v, i, a) { subtitlemenubuttons[i].setattribute('data-state', 'inactive'); }); // find the language to activate var lang = this.getattribute('lang'); for (var i = 0; i < video.texttracks.length; i++) { // for the 'subtitles-off' button, the first condition wi...
... initially the menu is hidden by default, so an event listener needs to be added to our subtitles button to toggle it: subtitles.addeventlistener('click', function(e) { if (subtitlesmenu) { subtitlesmenu.style.display = (subtitlesmenu.style.display == 'block' ?
Audio and Video Delivery - Developer guides
nt.getelementbyid('my-audio'); var mycontrol = document.getelementbyid('my-control'); function switchstate() { if (myaudio.paused == true) { myaudio.play(); mycontrol.innerhtml = "pause"; } else { myaudio.pause(); mycontrol.innerhtml = "play"; } } function checkkey(e) { if (e.keycode == 32 ) { //spacebar switchstate(); } } mycontrol.addeventlistener('click', function() { switchstate(); }, false); window.addeventlistener( "keypress", checkkey, false ); } you can try this example out here.
...o controls> <source src="dynamicsearch.mp4" type="video/mp4"></source> <a href="dynamicsearch.mp4"> <img src="dynamicsearch.jpg" alt="dynamic app search in firefox os"> </a> <p>click image to play a video demo of dynamic app search</p> </video> var v = document.queryselector('video'), sources = v.queryselectorall('source'), lastsource = sources[sources.length-1]; lastsource.addeventlistener('error', function(ev) { var d = document.createelement('div'); d.innerhtml = v.innerhtml; v.parentnode.replacechild(d, v); }, false); audio/video javascript libraries a number of audio and video javascript libaries exist.
Using device orientation with 3D transforms - Developer guides
here's a simple code snippet to sum it up: var elem = document.getelementbyid("view3d"); window.addeventlistener("deviceorientation", function(e) { // remember to use vendor-prefixed transform property elem.style.transform = "rotatez(" + ( e.alpha - 180 ) + "deg) " + "rotatex(" + e.beta + "deg) " + "rotatey(" + ( -e.gamma ) + "deg)"; }); orientation compensation compensating the orientation of the device can be useful to create parallax effects or augmented reality.
... this is achieved by inverting the previous order of rotations and negating the alpha value: var elem = document.getelementbyid("view3d"); window.addeventlistener("deviceorientation", function(e) { // again, use vendor-prefixed transform property elem.style.transform = "rotatey(" + ( -e.gamma ) + "deg)" + "rotatex(" + e.beta + "deg) " + "rotatez(" + - ( e.alpha - 180 ) + "deg) "; }); rotate3d to orientation should you ever need to convert a rotate3d axis-angle to orientation euler angles, you can use the following algorithm: // convert a rotate3d axis-angle to deviceorientation angles function orient( aa ) { var x = aa.x, y = aa.y, z = aa.z, a = aa.a, c = math.cos( aa.a ), s = math.sin( aa.a ), t = 1 - c, // axis-angle to rotation matrix rm...
User input and controls - Developer guides
for example if you want to add controls when any key gets pressed, you need to add an event listener on the window object: window.addeventlistener("keydown", handlekeydown, true); window.addeventlistener("keyup", handlekeyup, true); where handlekeydown and handlekeyup are the functions implementing the controls about the keydown and keyup events.
... if you want to use touch events, you need to add event listeners and specify handler functions, which will be called when the event gets fired: element.addeventlistener("touchstart", handlestart, false);
 element.addeventlistener("touchcancel", handlecancel, false);
 element.addeventlistener("touchend", handleend, false);
 element.addeventlistener("touchmove", handlemove, false); where element is the dom element you want to register the touch events on.
<dialog>: The Dialog element - HTML: Hypertext Markup Language
WebHTMLElementdialog
> </menu> <output aria-live="polite"></output> javascript var updatebutton = document.getelementbyid('updatedetails'); var favdialog = document.getelementbyid('favdialog'); var outputbox = document.queryselector('output'); var selectel = document.queryselector('select'); var confirmbtn = document.getelementbyid('confirmbtn'); // "update details" button opens the <dialog> modally updatebutton.addeventlistener('click', function onopen() { if (typeof favdialog.showmodal === "function") { favdialog.showmodal(); } else { alert("the <dialog> api is not supported by this browser"); } }); // "favorite animal" input sets the value of the submit button selectel.addeventlistener('change', function onselect(e) { confirmbtn.value = selectel.value; }); // "confirm" button of form triggers "close" o...
...n dialog because of [method="dialog"] favdialog.addeventlistener('close', function onclose() { outputbox.value = favdialog.returnvalue + " button clicked - " + (new date()).tostring(); }); result specifications specification status comment html living standardthe definition of '<dialog>' in that specification.
<input type="checkbox"> - HTML: Hypertext Markup Language
WebHTMLElementinputcheckbox
var overall = document.queryselector('input[id="enchtbl"]'); var ingredients = document.queryselectorall('ul input'); overall.addeventlistener('click', function(e) { e.preventdefault(); }); for(var i = 0; i < ingredients.length; i++) { ingredients[i].addeventlistener('click', updatedisplay); } function updatedisplay() { var checkedcount = 0; for(var i = 0; i < ingredients.length; i++) { if(ingredients[i].checked) { checkedcount++; } } if(checkedcount === 0) { overall.checked =...
...orm { width: 600px; margin: 0 auto; } div { margin-bottom: 10px; } fieldset { background: cyan; border: 5px solid blue; } legend { padding: 10px; background: blue; color: cyan; } javascript var othercheckbox = document.queryselector('input[value="other"]'); var othertext = document.queryselector('input[id="othervalue"]'); othertext.style.visibility = 'hidden'; othercheckbox.addeventlistener('change', () => { if(othercheckbox.checked) { othertext.style.visibility = 'visible'; othertext.value = ''; } else { othertext.style.visibility = 'hidden'; } }); specifications specification status comment html living standardthe definition of '<input type="checkbox">' in that specification.
<input type="color"> - HTML: Hypertext Markup Language
WebHTMLElementinputcolor
here's an example that watches changes over time to the color value: colorpicker.addeventlistener("input", updatefirst, false); colorpicker.addeventlistener("change", watchcolorpicker, false); function watchcolorpicker(event) { document.queryselectorall("p").foreach(function(p) { p.style.color = event.target.value; }); } selecting the value if the <input> element's implementation of the color type on the user's browser doesn't support a color well, but is instead a text field for ...
... var colorwell; var defaultcolor = "#0000ff"; window.addeventlistener("load", startup, false); initialization once the page is loaded, our load event handler, startup(), is called: function startup() { colorwell = document.queryselector("#colorwell"); colorwell.value = defaultcolor; colorwell.addeventlistener("input", updatefirst, false); colorwell.addeventlistener("change", updateall, false); colorwell.select(); } this gets a reference to the color...
Browser detection using the user agent - HTTP
, fall back to user agent sniffing var ua = navigator.useragent; hastouchscreen = ( /\b(blackberry|webos|iphone|iemobile)\b/i.test(ua) || /\b(android|windows phone|ipad|ipod)\b/i.test(ua) ); } } if (hastouchscreen) document.getelementbyid("examplebutton").style.padding="1em"; as for the screen size, simply use window.innerwidth and window.addeventlistener("resize", function(){ /*refresh screen size dependent things*/ }).
...function(mq) { for (var i=0,len=mql.length|0; i<len; i=i+1|0) if (mql[i][0] === mq) mql.splice(i, 1); mq.removelistener(whenmediachanges); } : listentomediaquery; var orientationchanged = false; addeventlistener("orientationchange", function(){ orientationchanged = true; }, passive_listener_option); addeventlistener("resize", settimeout.bind(0,function(){ if (orientationchanged && !mediaqueryupdated) for (var i=0,len=mql.length|0; i<len; i=i+1|0) mql[i][1]( mql[i][0] ); mediaqueryupdated = orientationchanged = false; },0)); which part of the user agent contains the infor...
this - JavaScript
it's not exactly dead because it gets executed, but it can be eliminated with no outside effects.) as a dom event handler when a function is used as an event handler, its this is set to the element on which the listener is placed (some browsers do not follow this convention for listeners added dynamically with methods other than addeventlistener()).
...e.currenttarget); // true when currenttarget and target are the same object console.log(this === e.target); this.style.backgroundcolor = '#a5d9f3'; } // get a list of every element in the document var elements = document.getelementsbytagname('*'); // add bluify as a click listener so when the // element is clicked on, it turns blue for (var i = 0; i < elements.length; i++) { elements[i].addeventlistener('click', bluify, false); } in an inline event handler when the code is called from an inline on-event handler, its this is set to the dom element on which the listener is placed: <button onclick="alert(this.tagname.tolowercase());"> show this </button> the above alert shows button.
Add to Home screen - Progressive web apps (PWAs)
we can then use a handler like the one below to handle the installation: window.addeventlistener('beforeinstallprompt', (e) => { // prevent chrome 67 and earlier from automatically showing the prompt e.preventdefault(); // stash the event so it can be triggered later.
... deferredprompt = e; // update ui to notify the user they can add to home screen addbtn.style.display = 'block'; addbtn.addeventlistener('click', (e) => { // hide our user interface that shows our a2hs button addbtn.style.display = 'none'; // show the prompt deferredprompt.prompt(); // wait for the user to respond to the prompt deferredprompt.userchoice.then((choiceresult) => { if (choiceresult.outcome === 'accepted') { console.log('user accepted the a2hs prompt'); } else { console.log('user dismissed the a2hs prompt'); } deferredprompt = null; }); }); }); so here we: call event.preventdefault() to stop chrome 67 and earlier from calling the install prompt automatically (this behavior changed in chrome 68).
Progressive web app structure - Progressive web apps (PWAs)
'http:///\'></a>','-'); content += entry; }; document.getelementbyid('content').innerhtml = content; next, it registers a service worker: if('serviceworker' in navigator) { navigator.serviceworker.register('/pwa-examples/js13kpwa/sw.js'); }; the next code block requests permission for notifications when a button is clicked: var button = document.getelementbyid("notifications"); button.addeventlistener('click', function(e) { notification.requestpermission().then(function(result) { if(result === 'granted') { randomnotification(); } }); }); the last block creates notifications that display a randomly-selected item from the games list: function randomnotification() { var randomitem = math.floor(math.random()*games.length); var notiftitle = games[random...
...on-192.png', '/pwa-examples/js13kpwa/icons/icon-256.png', '/pwa-examples/js13kpwa/icons/icon-512.png' ]; var gamesimages = []; for(var i=0; i<games.length; i++) { gamesimages.push('data/img/'+games[i].slug+'.jpg'); } var contenttocache = appshellfiles.concat(gamesimages); the next block installs the service worker, which then actually caches all the files contained in the above list: self.addeventlistener('install', function(e) { console.log('[service worker] install'); e.waituntil( caches.open(cachename).then(function(cache) { console.log('[service worker] caching all: app shell and content'); return cache.addall(contenttocache); }) ); }); last of all, the service worker fetches content from the cache if it is available there, providing offline functionality: self.adde...
Communicating using "port" - Archive of obsolete content
var pagemodscript = "window.addeventlistener('click', function(event) {" + " self.port.emit('click', event.target.tostring());" + " event.stoppropagation();" + " event.preventdefault();" + "}, false);" + "self.port.on('warning', function(message) {" + "window.alert(message);" + "});" var pagemod = r...
Porting the Library Detector - Archive of obsolete content
d two additional content scripts: one in the widget's context, which listens for icon mouseover events and sends a message to main.js containing the name of the corresponding library: function setlibraryinfo(element) { self.port.emit('setlibraryinfo', element.target.title); } var elements = document.getelementsbytagname('img'); for (var i = 0; i &lt; elements.length; i++) { elements[i].addeventlistener('mouseover', setlibraryinfo, false); } one in the panel, which updates the panel's content with the library information: self.on("message", function(libraryinfo) { window.document.body.innerhtml = libraryinfo; }); finally main.js relays the library information from the widget to the panel: widget.port.on('setlibraryinfo', function(libraryinfo) { widget.panel.postmessage(libraryinfo);...
frame/hidden-frame - Archive of obsolete content
the following code creates a hidden frame, loads a web page into it, and then logs its title: var hiddenframes = require("sdk/frame/hidden-frame"); let hiddenframe = hiddenframes.add(hiddenframes.hiddenframe({ onready: function() { this.element.contentwindow.location = "http://www.mozilla.org/"; let self = this; this.element.addeventlistener("domcontentloaded", function() { console.log(self.element.contentdocument.title); }, true, true); } })); see the panel module for a real-world example of usage of this module.
remote/parent - Archive of obsolete content
// remote.js const { frames } = require("sdk/remote/child"); frames.addeventlistener("pageshow", function() { // `this` is bound to the frame the event came from let frame = this; frame.port.emit("pageshow"); }, true); // main.js const { frames, remoterequire } = require("sdk/remote/parent"); remoterequire("./remote.js", module); // the first argument is the frame the message came from frames.port.on("pageshow", (frame) => { console.log(frame.frameelement.currenturi.hos...
Implementing the widget - Archive of obsolete content
the widget's content script the widget's content script just listens for left- and right- mouse clicks and posts the corresponding message to the add-on code: this.addeventlistener('click', function(event) { if(event.button == 0 && event.shiftkey == false) self.port.emit('left-click'); if(event.button == 2 || (event.button == 0 && event.shiftkey == true)) self.port.emit('right-click'); event.preventdefault(); }, true); save this in your data/widget directory as widget.js.
Display a Popup - Archive of obsolete content
var textarea = document.getelementbyid("edit-box"); textarea.addeventlistener('keyup', function onkeyup(event) { if (event.keycode == 13) { // remove the newline.
Canvas code snippets - Archive of obsolete content
add a listener to the // frame's onload event iframe.addeventlistener('load', this.remotepageloaded, true); //append to the end of the page window.document.body.appendchild(iframe); return; }; remotecanvas.prototype.remotepageloaded = function() { // look back up the iframe by id var ldrframe = document.getelementbyid('test-iframe'); // get a reference to the window object you need for the canvas // drawwindow method var remotewindo...
Customizing the download progress bar - Archive of obsolete content
wnloaditem = window.createdownloaditem; window.createdownloaditem = function(aattrs) { var dl = mydownloadmanager.defaultcreatedownloaditem(aattrs); if (dl) { if (...whatever condition you use to decide whether to change this download...) { dl.setattribute("myspecialdownload", "true"); } } return dl; } } }; window.addeventlistener("load", function(e) { mydownloadmanager.init(); }, false); in your css file, change richdownloaditem (both occurrences) to richdownloaditem[myspecialdownload="true"].
Drag & Drop - Archive of obsolete content
first, you need to hook up the basic drag event handlers: elem.addeventlistener("dragover", _dragover, true); elem.addeventlistener("dragdrop", _dragdrop, true); here, elem could be a window or an xul element.
HTML in XUL for rich tooltips - Archive of obsolete content
div.removechild(div.firstchild); //safely convert html string to a simple dom object, stripping it of javascript and more complex tags var injecthtml = components.classes["@mozilla.org/feed-unescapehtml;1"] .getservice(components.interfaces.nsiscriptableunescapehtml) .parsefragment(txt, false, null, div); //attach the dom object to the html div element div.appendchild(injecthtml); } } window.addeventlistener('load', htmltip.onload, false); in the xul overlay, xmlns:html is used to enable html tags to be used inside the xul.
Progress Listeners - Archive of obsolete content
r queryinterface: xpcomutils.generateqi(["nsiwebprogresslistener", "nsisupportsweakreference"]), onlocationchange: function(aprogress, arequest, auri) { this.processnewurl(auri); }, onstatechange: function() {}, onprogresschange: function() {}, onstatuschange: function() {}, onsecuritychange: function() {} }; window.addeventlistener("load", function() { myextension.init() }, false); window.addeventlistener("unload", function() { myextension.uninit() }, false); note: if you use the same listener for more than one tab/window, use awebprogress.domwindow in the callback methods to obtain the tab/window which triggers the state change or event.
Windows - Archive of obsolete content
example var startpos = null; function mousedown(event) { startpos = [event.clientx, event.clienty]; } function mousemove(event) { if (startpos) { var newx = event.screenx - startpos[0]; var newy = event.screeny - startpos[1]; window.moveto(newx, newy); } } function mouseup(event) { startpos = null; } window.addeventlistener("mousedown", mousedown, false); window.addeventlistener("mouseup", mouseup, false); window.addeventlistener("mousemove", mousemove, false); xul titlebar element xul applications can take advantage of the titlebar element to achieve a similar result without extra javascript code.
How to convert an overlay extension to restartless - Archive of obsolete content
erface(components.interfaces.nsiinterfacerequestor) .getinterface(components.interfaces.nsidomwindow); function onwindowload() { window.removeeventlistener("load",onwindowload); if (window.document.documentelement.getattribute("windowtype") == "navigator:browser") loadintowindow(window); } window.addeventlistener("load",onwindowload); }, onclosewindow: function(xulwindow) { }, onwindowtitlechange: function(xulwindow, newtitle) { } }; as mentioned above, components.utils.unload() will not work properly if the jsm file it is unloading is in a jar.
Inline options - Archive of obsolete content
some discussion on the subject at stackoverflow: how to use addeventlistener on inputchanged of inline options display notifications if you want to use the settings ui for anything more than storing preferences, then you will probably need to initialize them when they first appear.
Listening to events in Firefox extensions - Archive of obsolete content
} b.addeventlistener("event", callback, false) where b is the browser or tabbrowser you wish to watch for events from.
Offering a context menu for form controls - Archive of obsolete content
window.addeventlistener("load", function() { let settargetoriginal = nscontextmenu.prototype.settarget; components.utils.reporterror(settargetoriginal); nscontextmenu.prototype.settarget = function(anode, arangeparent, arangeoffset) { settargetoriginal.apply(this, arguments); if (this.istargetaformcontrol(anode)) this.shoulddisplay = true; }; }, false); this code, which is run whe...
Chapter 3: Introduction to XUL—How to build a more intuitive UI - Archive of obsolete content
var item = document.getelementbyid('menu-item-custom'); function handlecommandevent(aevent) { alert('ok'); item.removeeventlistener('command', handlecommandevent, false); item.parentnode.removechild(item); } item.addeventlistener('command', handlecommandevent, false); listing 11: additions and deletions using a dynamic event listener special menu items much like input elements in html, menuitem elements can operate like checkboxes and radio buttons by setting their type attributes.
Chapter 5: Let's build a Firefox extension - Archive of obsolete content
/ save session (event handler) save: function(event) { }, // restore session (event handler) restore: function(event) { }, // delete session (event handler) clear: function(event) { }, // dynamically generate menu items (event handler) createmenu: function(event) { }, // read file _readfile: function(afile) { }, // write file _writefile: function(afile, adata) { }, }; window.addeventlistener("load", function(){ gsessionstore.init(); }, false); window.addeventlistener("unload", function(){ gsessionstore.uninit(); }, false); wrap methods and variables as properties of objects you’ll note that in listing 15, i’ve defined a lot of different methods and variables as properties of a single object, gsessionstore.
Appendix B: Install and Uninstall Scripts - Archive of obsolete content
window.addeventlistener( "load", function() { xulschoolchrome.browseroverlay.init(); }, false); then all we need is some persistent flag that ensures that the first run code is only run once.
JavaScript Object Management - Archive of obsolete content
} // more stuff }; window.addeventlistener( "load", function() { 〈namespace〉.browseroverlay.init(); }, false); there are some things you can't (or shouldn't) do inside load handlers, such as closing the window being loaded, or opening new windows, alerts or dialogs.
Observer Notifications - Archive of obsolete content
*/ observe : function(asubject, atopic, adata) { if (atopic == "xulschoolhello-test-topic") { asubject.queryinterface(ci.nsisupportsstring); window.alert("subject: " + asubject.data); // => "this is a test" window.alert("data: " + adata); // => "hello" } } } window.addeventlistener( "load", function() { xulschoolchrome.browseroverlay.init(); }, false); window.addeventlistener( "unload", function() { xulschoolchrome.browseroverlay.uninit(); }, false); in the observe method the notification topic is verified because you can have one observer listening to several topics.
Session store API - Archive of obsolete content
istener like this: function myextensionhandlerestore(aevent) { var tab = event.originaltarget; /* the tab being restored */ var uri = tab.linkedbrowser.contentdocument.location; /* the tab's uri */ components.classes["@mozilla.org/consoleservice;1"] .getservice(components.interfaces.nsiconsoleservice) .logstringmessage("restoring tab: " + uri); }; document.addeventlistener("sstabrestoring", myextensionhandlerestore, false); simply replace the contents of the function myextensionhandlerestore() with whatever you need to do when the tab is restored.
Adding preferences to an extension - Archive of obsolete content
window.addeventlistener("load", function(e) { stockwatcher.startup(); }, false); window.addeventlistener("unload", function(e) { stockwatcher.shutdown(); }, false); design the preference dialog now that we've written all the code, we need to build the xul file for the options dialog.
Creating a dynamic status bar extension - Archive of obsolete content
we use the window.addeventlistener() dom function to tell firefox to call the stockwatcher.startup() function when a new browser window is opened: window.addeventlistener("load", function(e) { stockwatcher.startup(); }, false); our new extension has two primary functions: startup() and refreshinformation().
DOMSubtreeModified - Archive of obsolete content
document.body.addeventlistener('domsubtreemodified', function () { document.title = 'dom changed at ' + new date(); }, false); ...
MozOrientation - Archive of obsolete content
to normalize between the two you can do something like this: function orientationhandler(evt){ // for ff3.6+ if (!evt.gamma && !evt.beta) { evt.gamma = -(evt.x * (180 / math.pi)); evt.beta = -(evt.y * (180 / math.pi)); } // use evt.gamma, evt.beta, and evt.alpha // according to dev.w3.org/geo/api/spec-source-orientation } window.addeventlistener('deviceorientation', orientationhandler, false); window.addeventlistener('mozorientation', orientationhandler, false); example window.addeventlistener("mozorientation", dofunc, true); the example below simply displays the raw accelerometer data in the browser window as the events arrive.
chargingchange - Archive of obsolete content
"yes" : "no")); battery.addeventlistener('chargingchange', function() { console.log("battery charging?
chargingtimechange - Archive of obsolete content
example navigator.getbattery().then(function(battery) { console.log("battery charging time: " + battery.chargingtime + " seconds"); battery.addeventlistener('chargingtimechange', function() { console.log("battery charging time: " + battery.chargingtime + " seconds"); }); }); related events chargingchange dischargingtimechange levelchange ...
dischargingtimechange - Archive of obsolete content
example navigator.getbattery().then(function(battery) { console.log("battery discharging time: " + battery.dischargingtime + " seconds"); battery.addeventlistener('dischargingtimechange', function() { console.log("battery discharging time: " + battery.dischargingtime + " seconds"); }); }); related events chargingchange dischargingtimechange levelchange ...
levelchange - Archive of obsolete content
example navigator.getbattery().then(function(battery) { console.log("battery level: " + battery.level * 100 + " %"); battery.addeventlistener('levelchange', function() { console.log("battery level: " + battery.level * 100 + " %"); }); }); related events chargingchange chargingtimechange dischargingtimechange ...
Visualizing an audio spectrum - Archive of obsolete content
rect(0,0, canvas.width, canvas.height); for (var i = 0; i < fft.spectrum.length; i++ ) { // multiply spectrum by a zoom value magnitude = fft.spectrum[i] * 4000; // draw rectangle bars for each frequency bin ctx.fillrect(i * 4, canvas.height, 3, -magnitude); } } var audio = document.getelementbyid('audio-element'); audio.addeventlistener('mozaudioavailable', audioavailable, false); audio.addeventlistener('loadedmetadata', loadedmetadata, false); // fft from dsp.js, see below var fft = function(buffersize, samplerate) { this.buffersize = buffersize; this.samplerate = samplerate; this.spectrum = new float32array(buffersize/2); this.real = new float32array(buffersize...
Automated testing tips and tricks - Archive of obsolete content
ith chrome privileges using a chrome doc - see sbtests.xul in http://people.mozilla.com/~davel/scripts/ for an example firefox-bin -p sbtestprofile -chrome chrome://sbtests/content/ above code calls the quit function in quit.js to exit after test is finished how to detect content onload event from chrome use the domcontentloaded event chromewindow.addeventlistener('domcontentloaded',callbackfunction,false); ...
jspage - Archive of obsolete content
(this.getelementsbytagname(l.tagname)).contains(l);}return(this.contains)?(this!=l&&this.contains(l)):!!(this.comparedocumentposition(l)&16); },match:function(l){return(!l||(l==this)||(element.get(this,"tag")==l));}});native.implement([element,window,document],{addlistener:function(o,n){if(o=="unload"){var l=n,m=this; n=function(){m.removelistener("unload",n);l();};}else{h[this.uid]=this;}if(this.addeventlistener){this.addeventlistener(o,n,false);}else{this.attachevent("on"+o,n); }return this;},removelistener:function(m,l){if(this.removeeventlistener){this.removeeventlistener(m,l,false);}else{this.detachevent("on"+m,l);}return this; },retrieve:function(m,l){var o=c(this.uid),n=o[m];if(l!=undefined&&n==undefined){n=o[m]=l;}return $pick(n);},store:function(m,l){var n=c(this.uid);n[m]=l; return this;},elimin...
PyDOM - Archive of obsolete content
but addeventlistener within a <script type="application/x-python"> block does.
reserved - Archive of obsolete content
example here, the command to open a new browser window is reserved: <command id="cmd_newnavigator" oncommand="openbrowserwindow()" reserved="true"/> if the keyboard shortcut for that is accel-t, then this code will not work as expected, as compared to when it is run from web content: document.addeventlistener("keydown", handlekey, true); function handlekey(event) { // listen for the "new tab" shortcut if (event.metakey && (event.key == "t")) { // log a message console.log("intercepted accel-t"); // prevent the default browser action event.preventdefault(); event.stoppropagation(); } } currently, this event handler as coded above runs and logs the message, but t...
Dynamically modifying XUL-based user interface - Archive of obsolete content
you may also have used other calls, such as element.setattribute(), or, if you wrote an extension, the addeventlistener() method.
close - Archive of obsolete content
example window.addeventlistener("close", function( event ) { // make the close button ineffective event.preventdefault(); }, false); ...
findbar - Archive of obsolete content
possible values are: find_normal (0): normal find find_typeahead (1): typeahead find find_links (2): link find methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
Methods - Archive of obsolete content
sprogresslistener removetransientnotifications replacegroup reset rewind scrollbyindex scrollbypixels scrolltoindex select selectall selectitem selectitemrange selecttabatindex setselectionrange showpane showpopup sizeto startediting stop stopediting swapdocshells syncsessions timedselect toggleitemselection related dom element methods dom:element.addeventlistener dom:element.appendchild dom:element.comparedocumentposition dom:element.dispatchevent dom:element.getattribute dom:element.getattributenode dom:element.getattributenodens dom:element.getattributens dom:element.getelementsbytagname dom:element.getelementsbytagnamens dom:element.getfeature fixme: brokenlink dom:element.getuserdata dom:element.hasattribute dom:element.hasat...
Extensions - Archive of obsolete content
function init() { var contextmenu = document.getelementbyid("contentareacontextmenu"); if (contextmenu) contextmenu.addeventlistener("popupshowing", thumbnailsshowhideitems, false); } function thumbnailsshowhideitems(event) { var show = document.getelementbyid("thumbnail-show"); show.hidden = (document.popupnode.localname != "img"); } the init function should be called within the handler for the load event so that the popupshowing event handler is hooked up before it would be opened by the user.
PopupKeys - Archive of obsolete content
note that the last argument here is true to listen for events during the capturing phase of event propagation: window.addeventlistener("keypress", someaction, true); however, the default listener provides all the suitable responses to keys, so there shouldn't be a need to handle keys yourself.
textbox (Toolkit autocomplete) - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
Textbox (XPFE autocomplete) - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
Creating toolbar buttons (Customize Toolbar Window) - Archive of obsolete content
let button = doc.createelement("toolbarbutton"); button.setattribute("id", button_id); button.setattribute("label", "replace bookmark"); button.setattribute("class", "toolbarbutton-1 chromeclass-toolbar-additional"); button.setattribute("tooltiptext", "replace an existing bookmark"); button.style.liststyleimage = "url(" + icon + ")"; button.addeventlistener("command", main.action, false); toolbox.palette.appendchild(button); this code is thanks to dgutov and is seen in full context at his repository here at github: dgutov / bmreplace / bootstrap.js.
XUL Questions and Answers - Archive of obsolete content
specifying window.onload function to specify a function to run when the window is loaded,add the following code between the script tags in the xul file: window.addeventlistener("load", function(e) { startup(); }, false); similarly, for onunload use the code: window.addeventlistener("unload", function(e) { shutdown(); }, false); is there an event which is called when the firefox browser is initialized?
action - Archive of obsolete content
lign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
arrowscrollbox - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
assign - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
bbox - Archive of obsolete content
ArchiveMozillaXULbbox
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
binding - Archive of obsolete content
align, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
bindings - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
box - Archive of obsolete content
ArchiveMozillaXULbox
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
broadcaster - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
broadcasterset - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
browser - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
button - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
caption - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
checkbox - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
colorpicker - Archive of obsolete content
value property gets and sets color attribute methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
column - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
columns - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
command - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
commandset - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
conditions - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
content - Archive of obsolete content
métodos inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
datepicker - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
deck - Archive of obsolete content
ArchiveMozillaXULdeck
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
description - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
dialog - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
dialogheader - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
dropmarker - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
editor - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
grid - Archive of obsolete content
ArchiveMozillaXULgrid
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
grippy - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
groupbox - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
hbox - Archive of obsolete content
ArchiveMozillaXULhbox
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
iframe - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
image - Archive of obsolete content
ArchiveMozillaXULimage
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
key - Archive of obsolete content
ArchiveMozillaXULkey
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
keyset - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
label - Archive of obsolete content
ArchiveMozillaXULlabel
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
listbox - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
listcell - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
listcol - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
listcols - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
listhead - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
listheader - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
listitem - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
member - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
menu - Archive of obsolete content
ArchiveMozillaXULmenu
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
menubar - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
menuitem - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
menulist - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
menupopup - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
menuseparator - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
notification - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
notificationbox - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
observes - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
page - Archive of obsolete content
ArchiveMozillaXULpage
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
panel - Archive of obsolete content
ArchiveMozillaXULpanel
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
param - Archive of obsolete content
ArchiveMozillaXULparam
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
popupset - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
preference - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
preferences - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
prefpane - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
prefwindow - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
progressmeter - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
query - Archive of obsolete content
ArchiveMozillaXULquery
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
queryset - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
radio - Archive of obsolete content
ArchiveMozillaXULradio
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
radiogroup - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
resizer - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
richlistbox - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
richlistitem - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
row - Archive of obsolete content
ArchiveMozillaXULrow
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
rows - Archive of obsolete content
ArchiveMozillaXULrows
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
rule - Archive of obsolete content
ArchiveMozillaXULrule
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
scale - Archive of obsolete content
ArchiveMozillaXULscale
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
script - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
scrollbar - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
scrollbox - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
scrollcorner - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
separator - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
spacer - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
spinbuttons - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
splitter - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
stack - Archive of obsolete content
ArchiveMozillaXULstack
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
statusbar - Archive of obsolete content
align, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
<statusbarpanel> - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
stringbundle - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
stringbundleset - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
tab - Archive of obsolete content
ArchiveMozillaXULtab
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
tabbox - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
tabbrowser - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
tabpanel - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
tabpanels - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
tabs - Archive of obsolete content
ArchiveMozillaXULtabs
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
template - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
textbox - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
textnode - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
timepicker - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
titlebar - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbar - Archive of obsolete content
inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbarbutton - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbargrippy - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbaritem - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbarpalette - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbarseparator - Archive of obsolete content
align, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbarset - Archive of obsolete content
align, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbarspacer - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbarspring - Archive of obsolete content
align, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
toolbox - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
tooltip - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
tree - Archive of obsolete content
ArchiveMozillaXULtree
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treecell - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treechildren - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treecol - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treecols - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treeitem - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treerow - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
treeseparator - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
triple - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
vbox - Archive of obsolete content
ArchiveMozillaXULvbox
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
where - Archive of obsolete content
ArchiveMozillaXULwhere
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
window - Archive of obsolete content
ign, , allowevents, , boxobject, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
wizard - Archive of obsolete content
methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getuserdata, hasattribute(), hasattributens(), has...
wizardpage - Archive of obsolete content
object, builder, , , , classname, , , , , collapsed, contextmenu, controllers, database, datasources, dir, , , flex, height, hidden, id, , , left, , maxheight, maxwidth, menu, minheight, minwidth, , , , , , , observes, ordinal, orient, , pack, , persist, , , , ref, resource, , , , , statustext, style, ,, tooltip, tooltiptext, top, width methods inherited methods addeventlistener(), appendchild(), blur, click, clonenode(), comparedocumentposition, dispatchevent(), docommand, focus, getattribute(), getattributenode(), getattributenodens(), getattributens(), getboundingclientrect(), getclientrects(), getelementsbyattribute, getelementsbyattributens, getelementsbyclassname(), getelementsbytagname(), getelementsbytagnamens(), getfeature, getuserdata, hasattribute(), hasattrib...
Building XULRunner with Python - Archive of obsolete content
for example def onload(): btntest = document.getelementbyid("btntest") btntest.addeventlistener('command', ontest, false) def ontest(): window.alert('button activated') window.addeventlistener('load', onload, false) one possible gotcha is that the default python path used to find modules that areimported explicitly includes the xulrunner executable directory and the directory that is current when xulrunner launches.
CommandLine - Archive of obsolete content
var observerservice = components.classes["@mozilla.org/observer-service;1"] .getservice(components.interfaces.nsiobserverservice); observerservice.notifyobservers(window.arguments[0], "commandline-args-changed", null); addeventlistener("unload", observer.unregister, false); finally, add a reference in your application window to the observer: chrome/content/window.xul <?xml version="1.0"?> <?xml-stylesheet href="chrome://global/skin/" type="text/css"?> <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" id="main" title="&window.title;" windowtype="xulmine" style="width: 300px; height...
MacFAQ - Archive of obsolete content
uments[0] .queryinterface(components.interfaces.nsicommandline); for (var i = 0; i < cmdline.length; ++i) { debug(cmdline.getargument(i)) } } catch(ex) { debug(window.arguments[0]) // do something with window.arguments[0] //nspreferences.setunicharpref("myxul.cmdlinevalue", window.arguments[0]) } window.addeventlistener("load", checkotherwindows , false); } ]]></script> </window> ...
Scratchpad - Archive of obsolete content
for example, if you type document.addeventlistener, then press ctrl + shift + space, you'll see a popup that shows a summary of the function's syntax and a short description: the "[docs]" link takes you to the mdn documentation for the symbol.
-ms-filter - Archive of obsolete content
alt="sphere"> <div id="filterto" style="position: absolute; width: 200px; height: 250px; top: 20px; left: 20px; background: white; visibility: hidden;"> </div> </div> <script type="text/javascript"> let filterimg = document.queryselector('#filterfrom'); filterimg.addeventlistener('click', dofilter); function dofilter () { filterfrom.filters.item(0).apply(); // 12 is the dissolve filter.
Expression closures - Archive of obsolete content
examples a shorthand for binding event listeners: document.addeventlistener('click', function() false, true); using this notation with some of the array functions from javascript 1.6: elems.some(function(elem) elem.type == 'text'); ...
Window: devicelight event - Archive of obsolete content
examples window.addeventlistener('devicelight', function(event) { console.log(event.value); }); specifications specification status comment ambient light sensorthe definition of 'ambient light events' in that specification.
Displaying a graphic with audio samples - Archive of obsolete content
{ // multiply spectrum by a zoom value magnitude = signal[i] * 1000; // draw rectangle bars for each frequency bin ctx.fillrect(i * 4, canvas.height, 3, -magnitude); } ctx.drawimage(document.getelementbyid('mozlogo'),0,0, canvas.width, canvas.height); } var audio = document.getelementbyid('audio-element'); audio.addeventlistener('mozaudioavailable', audioavailable, false); audio.addeventlistener('loadedmetadata', loadedmetadata, false); </script> </body> </html> ...
Desktop mouse and keyboard controls - Game development
first, we'd need an event listener to listen for the pressed keys: document.addeventlistener('keydown', keydownhandler, false); document.addeventlistener('keyup', keyuphandler, false); whenever any key is pressed down, we're executing the keydownhandler function, and when press finishes we're executing the keyuphandler function, so we know when it's no longer pressed.
Implementing controls using the Gamepad API - Game development
next, we set up two event listeners to get the data: window.addeventlistener("gamepadconnected", gamepadapi.connect); window.addeventlistener("gamepaddisconnected", gamepadapi.disconnect); due to security policy, you have to interact with the controller first while the page is visible for the event to fire.
Mouse controls - Game development
add the following line in the same place as the other event listeners, just below the keyup event: document.addeventlistener("mousemove", mousemovehandler, false); anchoring the paddle movement to the mouse movement we can update the paddle position based on the pointer coordinates — the following handler function will do exactly that.
2D maze game with device orientation - Game development
here’s the code from the create() function responsible for this: window.addeventlistener("deviceorientation", this.handleorientation, true); we’re adding an event listener to the "deviceorientation" event and binding the handleorientation function which looks like this: handleorientation: function(e) { var x = e.gamma; var y = e.beta; ball._player.body.velocity.x += x; ball._player.body.velocity.y += y; }, the more you tilt the device, the more force is applied t...
jQuery - MDN Web Docs Glossary: Definitions of Web-related terms
$(document).ready(function(){ alert("hello world!"); $("#blackbox").hide(); }); the above code carries out the same function as the following code: window.onload = function() { alert("hello world!"); document.getelementbyid("blackbox").style.display = "none"; }; or: window.addeventlistener("load", () => { alert("hello world!"); document.getelementbyid("blackbox").style.display = "none"; }); learn more general knowledge jquery on wikipedia jquery official website technical information offical api reference documentation ...
Fundamental text and font styling - Learn web development
set = document.getelementbyid("reset"); let htmlcode = htmlinput.value; let csscode = cssinput.value; const output = document.queryselector(".output"); const styleelem = document.createelement('style'); const headelem = document.queryselector('head'); headelem.appendchild(styleelem); function drawoutput() { output.innerhtml = htmlinput.value; styleelem.textcontent = cssinput.value; } reset.addeventlistener("click", function() { htmlinput.value = htmlcode; cssinput.value = csscode; drawoutput(); }); htmlinput.addeventlistener("input", drawoutput); cssinput.addeventlistener("input", drawoutput); window.addeventlistener("load", drawoutput); test your skills!
The HTML5 input types - Learn web development
to actually display the current value, and update it as it changed, you must use javascript, but this is relatively easy to do: const price = document.queryselector('#price'); const output = document.queryselector('.price-output'); output.textcontent = price.value; price.addeventlistener('input', function() { output.textcontent = price.value; }); here we store references to the range input and the output in two variables.
Example 2 - Learn web development
lid #000; border-top-width : .1em; border-radius: 0 0 .4em .4em; box-shadow: 0 .2em .4em rgba(0,0,0,.4); -moz-box-sizing : border-box; box-sizing : border-box; min-width : 100%; max-height: 10em; /* 100px */ overflow-y: auto; overflow-x: hidden; } .select .option { padding: .2em .3em; } .select .highlight { background: #000; color: #ffffff; } javascript content window.addeventlistener("load", function () { var form = document.queryselector('form'); form.classlist.remove("no-widget"); form.classlist.add("widget"); }); result for js no js html content <form class="no-widget"> <select name="myfruit"> <option>cherry</option> <option>lemon</option> <option>banana</option> <option>strawberry</option> <option>apple</option> </select> <div ...
UI pseudo-classes - Learn web development
now finally, we've used some javascript to toggle the disabling of the billing address fields: // wait for the page to finish loading document.addeventlistener('domcontentloaded', function () { // attach `change` event listener to checkbox document.getelementbyid('billing-checkbox').addeventlistener('change', togglebilling); }, false); function togglebilling() { // select the billing text fields let billingitems = document.queryselectorall('#billing input[type="text"]'); // select the billing text labels let billinglabels = document.querys...
Use JavaScript within a webpage - Learn web development
<script> window.addeventlistener('load', function () { console.log('this function is executed once the page is fully loaded'); }); </script> that's convenient when you just need a small bit of javascript, but if you keep javascript in separate files you'll find it easier to focus on your work write self-sufficient html write structured javascript applications use scripting accessibly accessibility is a major issue in ...
Graceful asynchronous programming with Promises - Learn web development
note: the way that a .then() block works is similar to when you add an event listener to an object using addeventlistener().
Basic math in JavaScript — numbers and operators - Learn web development
for now, let's look at a quick example: <button>start machine</button> <p>the machine is stopped.</p> const btn = document.queryselector('button'); const txt = document.queryselector('p'); btn.addeventlistener('click', updatebtn); function updatebtn() { if (btn.textcontent === 'start machine') { btn.textcontent = 'stop machine'; txt.textcontent = 'the machine has started!'; } else { btn.textcontent = 'start machine'; txt.textcontent = 'the machine is stopped.'; } } open in new window you can see the equality operator being used just inside the updatebtn() function.
Solve common problems in your JavaScript code - Learn web development
what does the addeventlistener() function do, and how do you use it?
Ember interactivity: Events, classes and state - Learn web development
we can capture the keydown event via the on modifier, which is just ember syntactic sugar around addeventlistener and removeeventlistener (see this explanation if needed).
Introduction to client-side frameworks - Learn web development
read more about the javascript used in this section: document.createelement() document.createtextnode() document.createdocumentfragment() eventtarget.addeventlistener() node.appendchild() node.removechild() another way to build uis every javascript framework offers a way to write user interfaces more declaratively.
React interactivity: Events and state - Learn web development
for example: const btn = document.queryselector('button'); btn.addeventlistener('click', () => { alert("hi!"); }); in react, we write event handlers directly on the elements in our jsx, like this: <button type="button" onclick={() => alert("hi!")} > say hi!
TypeScript support in Svelte - Learn web development
it should end up looking like this: // actions.ts export function selectonfocus(node: htmlinputelement) { if (node && typeof node.select === 'function' ) { // make sure node is defined and has a select() method const onfocus = () => node.select() // event handler node.addeventlistener('focus', onfocus) // when node gets focus call onfocus() return { destroy: () => node.removeeventlistener('focus', onfocus) // this will be executed when the node is removed from the dom } } } now update todo.svelte and newtodo.svelte where we import the actions file.
Adding a new todo form: Vue events, methods, and models - Learn web development
.passive: equivalent to using the { passive: true } parameter when creating an event listener in vanilla javascript using addeventlistener().
Handling common accessibility problems - Learn web development
addeventlistener won't work.
Frame script environment
addeventlistener() listen to events from content.
Limitations of chrome scripts
for example: addeventlistener("load", handler, true) // for example if you need to contact the chrome process when that happens, send it a message.
Frame script environment
addeventlistener() listen to events from content.
Frame script loading and lifetime
var gcontentframemessagemanager = this; addeventlistener('unload', function(aevent) { if (aevent.target == gcontentframemessagemanager) { sendasyncmessage('my-addon-id', 'framescript-died'); // if you did not set third argument of `services.mm.addmessagelistener` to `true`, then this will fail to send a message } }, false); note about unload during uninstallation/upgrade when your add-on is uninstalled, or disabled, you should: can...
Message manager overview
its most important attributes and functions are: content : access the dom window hosted by the tab docshell : access the top-level docshell components : access privileged objects and apis addeventlistener() : listen to dom events addmessagelistener() : receive messages from the chrome process sendasyncmessage() : send asynchronous messages to the chrome process sendsyncmessage() : send synchronous messages to the chrome process interfaces nsidomeventtarget nsimessagelistenermanager nsimessagesender nsisyncmessagesender nsicontentframemessagem...
HTMLIFrameElement.clearMatch()
searchtoggle.addeventlistener('touchend',function() { if(search.getattribute('class') === 'search') { search.setattribute('class', 'search shifted'); } else if(search.getattribute('class') === 'search shifted') { search.setattribute('class', 'search'); if(searchactive) { browser.clearmatch(); searchactive = false; prev.disabled = true; next.disabled = true; searchbar.value = ''; ...
HTMLIFrameElement.findAll()
searchform.addeventlistener('submit', function(e) { e.preventdefault(); browser.findall(searchbar.value, 'case-sensitive'); searchactive = true; prev.disabled = false; next.disabled = false; searchbar.blur(); }); specification not part of any specification.
HTMLIFrameElement.findNext()
prev.addeventlistener('touchend',function() { browser.findnext('backward'); }); next.addeventlistener('touchend',function() { browser.findnext('forward'); }); specification not part of any specification.
HTMLIFrameElement.getManifest()
examples var browser = document.queryselector('iframe'); browser.addeventlistener('mozbrowserloadend',function() { var request = browser.getmanifest().then(function(json) { console.log(json); }); }); specification not part of any specification.
HTMLIFrameElement.getStructuredData()
examples var browser = document.queryselector('iframe'); browser.addeventlistener('mozbrowserloadend',function() { var request = browser.getstructureddata(); request.onsuccess = function() { console.log(request.result); } }); running this code in a browser api app and then loading up a page that contains microdata (such as the website of british alt-country band salter cane) will result in a json object being returned, along the lines of: { "items": [ {...
HTMLIFrameElement.goBack()
examples back.addeventlistener('touchend',function() { browser.goback(); }); specification not part of any specification.
HTMLIFrameElement.goForward()
examples fwd.addeventlistener('touchend',function() { browser.goforward(); }); specification not part of any specification.
mozbrowseractivitydone
examples var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowseractivitydone", function(event) { if(event.details.success) { console.log('activity completed successfully'); } else { console.log('activity not completed successfully'); } }); related events mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowserse...
mozbrowserasyncscroll
examples var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserasyncscroll", function( event ) { console.log("the scroll top position of the document is:" + event.details.top + "px"); }); related events mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernameandpassw...
mozbrowseraudioplaybackchange
examples var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowseraudioplaybackchange", function(event) { console.log(event.details); }); related events mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowsercaretstatechanged
examples var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsercaretstatechanged", function( event ) { // do stuff with event.details }); related events mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowserclose
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserclose", function() { console.log("browser window has been closed; iframe will be destroyed."); }); related events mozbrowserasyncscroll mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernamea...
mozbrowsercontextmenu
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsercontextmenu", function(event) { console.log("asking for menu:" + json.stringify(event.details)); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernameandpa...
mozbrowserdocumentfirstpaint
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserdocumentfirstpaint", function() { console.log("first content painted."); }); related events mozbrowserasyncscroll mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowsererror
t cspblocked phishingblocked malwareblocked unwantedblocked offline malformeduri redirectloop unknownsockettype netreset notcached isprinting deniedportaccess proxyresolvefailure proxyconnectfailure contentencodingfailure remotexul unsafecontenttype corruptedcontenterror certerror other example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsererror", function( event ) { console.log("an error occurred:" + event.detail); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernameandpasswordrequire...
mozbrowserfindchange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserfindchange", function(event) { console.log("currently highlighted: " + event.details.activematchordinal + " out of " + event.details.numberofmatches); }); related events mozbrowserasyncscroll mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange ...
mozbrowserfirstpaint
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserfirstpaint", function(event) { console.log("first content painted."); }); related events mozbrowserasyncscroll mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowsericonchange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsericonchange", function( event ) { console.log("the url of the new favicon is:" + event.details.href); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusername...
mozbrowserloadend
var browser = document.queryselector("iframe"); browser.addeventlistener('mozbrowserloadend',function(e) { stopreload.textcontent = 'r'; console.log(e.detail.backgroundcolor); controls.style.background = e.detail.backgroundcolor; }); browser.addeventlistener('mozbrowserloadend',function() { stopreload.textcontent = 'r'; }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadst...
mozbrowserloadstart
var browser = document.queryselector("iframe"); browser.addeventlistener('mozbrowserloadstart',function() { stopreload.textcontent = 'x'; }); browser.addeventlistener('mozbrowserloadend',function() { stopreload.textcontent = 'r'; }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodal...
mozbrowserlocationchange
var browser = document.queryselector("iframe"); browser.addeventlistener('mozbrowserlocationchange', function (event) { urlbar.value = event.detail.url; }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowsermanifestchange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsermanifestchange", function(event) { console.log("new manifest url: " + event.details.href); }); related events mozbrowserasyncscroll mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowsertitlechange mozbrowserusernameandpa...
mozbrowsermetachange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsermetachange", function(event) { console.log("a meta tag has been " + event.details.type + ".
mozbrowseropensearch
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowseropensearch", function( event ) { console.log("new search engine encountered: " + event.details.title); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsertitlechange ...
mozbrowseropentab
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowseropentab", function( event ) { console.log("a new document has opened containing the content at " + event.details.url + "."); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernameand...
mozbrowseropenwindow
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowseropenwindow", function( event ) { console.log("a new window has opened containing the content at " + event.details.url + "."); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernamean...
mozbrowserresize
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserresize", function( event ) { console.log("the new window size is " + event.details.width + " x " + event.details.height + "."); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusername...
mozbrowserscroll
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserscroll", function( event ) { console.log("the new scroll position is " + event.details.left + " across and " + event.details.top + "down."); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowsersecuritychange mozbrowsertitl...
mozbrowserscrollareachanged
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserscrollareachanged", function( event ) { console.log("the new scroll area is " + event.details.width + " x " + event.details.height + "."); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowsersecuritychange mozbrowsertitlec...
mozbrowserscrollviewchange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserscrollviewchange", function( event ) { console.log("scrolling has " + event.details.state + "."); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowsersecuritychange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsersecuritychange", function( event ) { console.log("the ssl state is:" + event.details.state); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsertitlechange mozbrowserusernameandpasswordrequired ...
mozbrowserselectionstatechanged
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowserselectionstatechanged", function( event ) { if(event.details.visible) { console.log("the current selection is visible."); } else { console.log("the current selection is not visible."); } }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchan...
mozbrowsershowmodalprompt
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsershowmodalprompt", function( event ) { console.log("asking for prompt:" + json.stringify(event.detail)); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsertitlechange mozbrowserusernamean...
mozbrowsertitlechange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowsertitlechange", function( event ) { console.log("the title of the document is:" + event.detail); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsershowmodalprompt mozbrowserusernameandpass...
mozbrowserusernameandpasswordrequired
example var browser = document.queryselector("iframe[mozbrowser]"); browser.addeventlistener("mozbrowserusernameandpasswordrequired", function( event ) { console.log("the auth realm is:" + event.detail.realm); }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozbrowsersecuritychange mozbrowsertitlechange ...
mozbrowservisibilitychange
example var browser = document.queryselector("iframe"); browser.addeventlistener("mozbrowservisibilitychange", function( event ) { if(event.details.visible) { console.log("the browser is visible."); } else { console.log("the browser is hidden."); } }); related events mozbrowserasyncscroll mozbrowserclose mozbrowsercontextmenu mozbrowsererror mozbrowsericonchange mozbrowserloadend mozbrowserloadstart mozbrowserlocationchange mozbrowseropenwindow mozb...
HTMLIFrameElement.reload()
examples stopreload.addeventlistener('touchend',function() { if(stopreload.textcontent === 'x') { browser.stop(); } else { browser.reload(); } }); specification not part of any specification.
HTMLIFrameElement.stop()
MozillaGeckoChromeAPIBrowser APIstop
examples stopreload.addeventlistener('touchend',function() { if(stopreload.textcontent === 'x') { browser.stop(); } else { browser.reload(); } }); specification not part of any specification.
HTMLIFrameElement.zoom()
MozillaGeckoChromeAPIBrowser APIzoom
examples var browser = document.queryselector('iframe'); var zoomfactor = 1; zoomin.addeventlistener('touchend',function() { zoomfactor += 0.1; browser.zoom(zoomfactor); }); zoomout.addeventlistener('touchend',function() { zoomfactor -= 0.1; browser.zoom(zoomfactor); }); specification not part of any specification.
Browser API
the following methods are used to deal with those events: the <iframe> gains support for the methods of the eventtarget interface addeventlistener(), removeeventlistener(), and dispatchevent().
overflow-clip-box-block
oll { overflow: auto; padding: 0 30px; width: 6em; border: 1px solid black; background: lime content-box; } .padding-box { overflow-clip-box-block: padding-box; } javascript function scrollsomeelements() { var elms = document.queryselectorall('.scroll'); for (i=0; i < elms.length; ++i) { elms[i].scrollleft=80; } } var elt = document.queryelementsbytagname('body')[0]; elt.addeventlistener("load", scrollsomeelements, false); result specifications this property has been proposed to the w3c csswg; it is not yet on the standard track but, if accepted, should appear in css overflow module level 3.
overflow-clip-box-inline
ll { overflow: auto; padding: 0 30px; width: 6em; border: 1px solid black; background: lime content-box; } .padding-box { overflow-clip-box-inline: padding-box; } javascript function scrollsomeelements() { var elms = document.queryselectorall('.scroll'); for (i=0; i < elms.length; ++i) { elms[i].scrollleft=80; } } var elt = document.queryelementsbytagname('body')[0]; elt.addeventlistener("load", scrollsomeelements, false); result specifications this property has been proposed to the w3c csswg; it is not yet on the standard track but, if accepted, should appear in css overflow module level 3.
overflow-clip-box
v> css .scroll { overflow: auto; padding: 0 30px; width: 6em; border: 1px solid black; background: lime content-box; } .padding-box { overflow-clip-box: padding-box; } js function scrollsomeelements() { var elms = document.queryselectorall('.scroll'); for (i=0; i < elms.length; ++i) { elms[i].scrollleft=80; } } var elt = document.queryelementsbytagname('body')[0]; elt.addeventlistener("load", scrollsomeelements, false); result specifications this property has been proposed to the w3c csswg; it is not yet on the standard track but, if accepted, should appear in css overflow module level 3.
MozBeforePaint
ackground:lime; position:relative;"></div> <script> var d = document.getelementbyid("d"); var start = window.mozanimationstarttime; function step(event) { var progress = event.timestamp - start; d.style.left = math.min(progress/10, 200) + "px"; if (progress < 2000) { window.mozrequestanimationframe(); } else { window.removeeventlistener("mozbeforepaint", step, false); } } window.addeventlistener("mozbeforepaint", step, false); window.mozrequestanimationframe(); </script> </body> </html> as you can see, each time the mozbeforepaint event fires, our step() method is called.
MozScrolledAreaChanged
example document.addeventlistener("mozscrolledareachanged", event => { // find something useful to do with those values event.width; event.height; event.x; event.y; }, false); ...
smartcard-insert
example document.addeventlistener("smartcard-insert", smartcardchangehandler ); related events smartcard-remove ...
smartcard-remove
example document.addeventlistener("smartcard-remove", smartcardchangehandler ); related events smartcard-insert ...
WebChannel.jsm
chrome code and a webpage chrome code let channel = new webchannel(webchannelid, services.io.newuri("https://mozilla.org", null, null)); // receive messages channel.listen(function (webchannelid, message, sendercontext) { // send messages channel.send({ data: { greeting: true } }, sendercontext); }); webpage code receive messages from an existing webchannel in content code window.addeventlistener("webchannelmessagetocontent", function(e) { // receive messages console.log(e.detail); }, true); send messages to an existing webchannel in chrome code window.dispatchevent(new window.customevent("webchannelmessagetochrome", { detail: { id: webchannelid, message: { something: true } } })); ...
Extras
> </mrow> </mfrac> </mrow> </math> </foreignobject> <text>exp(α)</text> </switch> </g> </g> </svg> </div> inline javascript html content <math display="block"> <mfrac> <mtext id="num">mouse</mtext> <mtext id="denum">over</mtext> </mfrac> </math> javascript content function whoistherealert(evt) { alert("who is there?"); } function attachlistener(id) { document.getelementbyid(id).addeventlistener("mouseover", whoistherealert); } function init() { attachlistener("num"); attachlistener("denum"); } window.addeventlistener("load", init); ...
MathML Torture Test
addeventlistener("change", updatemathfont, false) } window.addeventlistener("load", load, false); the following test contains sample tex formulas from knuth's tex book and equivalent mathml representations.
MathML In Action
addeventlistener("click", zoomtoggle, false); } window.addeventlistener("load", load, false); consider an interesting markup like this { u t + f ( u ) x = 0 u ( 0 , x ) = { u - if x < 0 u + if x > 0 or other complex markups like these ell ^ y ( z ; z , τ ) := ∫ y ( ∏ l ( y l 2 π i ) θ ( y l 2 π i - z ) θ ′...
Mozilla DOM Hacking Guide
"interface flattening is the ability to call methods on an object regardless of the interface it was defined on." for example, when we have the document object in javascript, we can call indistinctly document.getelementbyid(), or document.addeventlistener(), although they are defined on two different interfaces (domdocument and domeventtarget.
Scroll-linked effects
ipt> function snap(destination) { if (math.abs(destination - window.scrolly) < 3) { scrollto(window.scrollx, destination); } else if (math.abs(destination - window.scrolly) < 200) { scrollto(window.scrollx, window.scrolly + ((destination - window.scrolly) / 2)); settimeout(snap, 20, destination); } } var timeoutid = null; addeventlistener("scroll", function() { if (timeoutid) cleartimeout(timeoutid); timeoutid = settimeout(snap, 200, parseint(document.getelementbyid('snaptarget').style.top)); }, true); </script> <div id="snaptarget" class="snaptarget" style="position: relative; top: 200px; width: 100%; height: 200px; background-color: green"></div> </body> in this example, there is a scroll event listener wh...
L20n HTML Bindings
when all dom nodes are localized, the document element will fire a documentlocalized event, which you can listen to: document.addeventlistener('documentlocalized', function() { // the dom has been localized and the user sees it in their language yourapp.init(); }); exposing context data you can expose important bits of data to the localization context in form of context data.
nsIEventListenerInfo
this approach is necessary because event listeners added with addeventlistener won't necessarily be nsieventlisteners; the dom code will fix up ordinary javascript functions to act as listeners.
nsIPushSubscription
getservice(ci.nsiscriptsecuritymanager); const pushservice = cc["@mozilla.org/push/service;1"] .getservice(ci.nsipushservice); function sendsubscriptiontoserver(subscription) { let request = cc["@mozilla.org/xmlextras/xmlhttprequest;1"] .createinstance(ci.nsixmlhttprequest); request.open("post", "https://example.com/register-for-push", true); request.addeventlistener("error", () => { cu.reporterror("error sending subscription to server"); }); request.send(json.stringify({ endpoint: subscription.endpoint, // base64-encode the key and authentication secret.
Adding items to the Folder Pane
the following code snippet listens for that event: let gnumbersext = { load: function gne_load() { window.removeeventlistener("load", gnumbersext.load, false); let tree = document.getelementbyid("foldertree"); tree.addeventlistener("maprebuild", gnumbersext._insert, false); }, _insert: function gne__insert() { // this function is called when a rebuild occurs } }; window.addeventlistener("load", gnumbersext.load, true); the structure of folder-tree-items the folder pane stores its current display data in a property called _rowmap.
Building a Thunderbird extension 6: Adding JavaScript
window.addeventlistener("load", function(e) { startup(); }, false); window.setinterval( function() { startup(); }, 60000); //update date every minute function startup() { var mypanel = document.getelementbyid("my-panel"); var date = new date(); var day = date.getday(); var datestring = date.getfullyear() + "." + (date.getmonth()+1) + "." + date.getdate(); mypanel.label = "date: " + datestring; } the first p...
Creating a Custom Column
window.addeventlistener("load", doonceloaded, false); function doonceloaded() { var observerservice = components.classes["@mozilla.org/observer-service;1"].getservice(components.interfaces.nsiobserverservice); observerservice.addobserver(createdbobserver, "msgcreatedbview", false); } var createdbobserver = { // components.interfaces.nsiobserver observe: function(amsgfolder, atopic, adata) { addcustomcol...
Access Window
check if the window is a tab or the root window window.addeventlistener("load", function(e) { alert("is root?: " + isroot()); }, false); function isroot() { if(window != window.top) return "false"; else return "true"; } the example above tells you if the window object is a reference of the application window or of one of it is a tabs.
Detect Opening Folder
to do this you need to capture the select event of the folder [[xul:tree|tree]] whose id is (conveniently) foldertree like so: window.document.getelementbyid('foldertree').addeventlistener("select", testcolumns, false); ...
Filter Incoming Mail
d we're done amsghdr.subject = mimeconvert.encodemimepartiistr_utf8(subject, false, "utf-8", 0, 72); } } }; function init() { var notificationservice = components.classes["@mozilla.org/messenger/msgnotificationservice;1"] .getservice(components.interfaces.nsimsgfoldernotificationservice); notificationservice.addlistener(newmaillistener, notificationservice.msgadded); } addeventlistener("load", init, true); have a look to nsimsgdbhdr to get the full list of properties to be modified.
Use SQLite
bfile); } this.dbconnection = dbconnection; }, _dbcreate: function(adbservice, adbfile) { var dbconnection = adbservice.opendatabase(adbfile); this._dbcreatetables(dbconnection); return dbconnection; }, _dbcreatetables: function(adbconnection) { for(var name in this.dbschema.tables) adbconnection.createtable(name, this.dbschema.tables[name]); }, }; window.addeventlistener("load", function(e) { tbirdsqlite.onload(e); }, false); this is another practical sample on how to handle opendatabase and sql queries on the client side, using in-memory (blob) storage of 2mb: var db = opendatabase('mydb', '1.0', 'test db', 2 * 1024 * 1024); var msg; db.transaction(function (tx) { tx.executesql('create table if not exists logs (id unique, log)'); tx.executesql('insert into...
WebIDL bindings
return this.__dom_impl__.geteventhandler("onmyevent"); }, set onmyevent(handler) { this.__dom_impl__.seteventhandler("onmyevent", handler); }, dispatchtheevent: function() { var event = new this.contentwindow.event("myevent"); this.__dom_impl__.dispatchevent(event); }, }; the implementation would automatically support the api exposed on eventtarget (so, for example, addeventlistener).
Add to iPhoto
if (document.getelementbyid("contentareacontextmenu")) { document.getelementbyid("contentareacontextmenu").addeventlistener("popupshowing", iphoto.onpopup, false); } responding when the context menu is clicked when the user right-clicks an image, our handler gets called: onpopup: function() { var node = iphoto.getcurrentnode(); var item = document.getelementbyid("add-to-iphoto_menuitem"); if (item) { item.hidden = (node == null); // hide it if we're not on an image } } this code finds the image nod...
Debug eval sources - Firefox Developer Tools
in the video below, we load a page containing a source like this: var script = `function foo() { console.log('called foo'); } //# sourceurl=my-foo.js`; eval(script); var button = document.getelementbyid("foo"); button.addeventlistener("click", foo, false); the evaluated string is given the name "my-foo.js" using the //# sourceurl directive.
DevTools API - Firefox Developer Tools
window.document.body.addeventlistener("click", this.handleclick); } mypanel.prototype = { open: function() { // any asynchronous operations should be done here.
Monster example - Firefox Developer Tools
for (var i = 0; i &lt; monster_count; i++) { monsters.friendly.push(new monster()); } for (var i = 0; i &lt; monster_count; i++) { monsters.fierce.push(new monster()); } for (var i = 0; i &lt; monster_count; i++) { monsters.undecided.push(new monster()); } console.log(monsters); } var makemonstersbutton = document.getelementbyid("make-monsters"); makemonstersbutton.addeventlistener("click", makemonsters); the page contains a button: when you push the button, the code creates some monsters.
Animation inspector example: CSS transitions - Firefox Developer Tools
utton != 0) { return; } if (e.target.classlist.contains("icon")) { var wasselected = (e.target.getattribute("id") == "selected"); clearselection(); if (!wasselected) { e.target.setattribute("id", "selected"); } } } function clearselection() { var selected = document.getelementbyid("selected"); if (selected) { selected.removeattribute("id"); } } document.addeventlistener("click", toggleselection); ...
Animation inspector example: Web Animations API - Firefox Developer Tools
keyframeset, notekeyframeoptions); iconanimation.pause(); noteanimation.pause(); var firsttime = true; function animatechannel(e) { if (e.button != 0) { return; } if (e.target.id != "icon") { return; } if (firsttime) { iconanimation.play(); noteanimation.play(); firsttime = false; } else { iconanimation.reverse(); noteanimation.reverse(); } } document.addeventlistener("click", animatechannel); ...
Waterfall - Firefox Developer Tools
for example, consider code like this: var timerbutton = document.getelementbyid("timer"); timerbutton.addeventlistener("click", handleclick, false); function handleclick() { console.time("timer"); runtimer(1000).then(timerfinished); } function timerfinished() { console.timeend("timer"); console.log("ready!"); } function runtimer(t) { return new promise(function(resolve) { settimeout(resolve, t); }); } the waterfall will display a marker for the period between time() and timeend(), and if you s...
AbortController.AbortController() - Web APIs
var controller = new abortcontroller(); var signal = controller.signal; var downloadbtn = document.queryselector('.download'); var abortbtn = document.queryselector('.abort'); downloadbtn.addeventlistener('click', fetchvideo); abortbtn.addeventlistener('click', function() { controller.abort(); console.log('download aborted'); }); function fetchvideo() { ...
AbortController.abort() - Web APIs
var controller = new abortcontroller(); var signal = controller.signal; var downloadbtn = document.queryselector('.download'); var abortbtn = document.queryselector('.abort'); downloadbtn.addeventlistener('click', fetchvideo); abortbtn.addeventlistener('click', function() { controller.abort(); console.log('download aborted'); }); function fetchvideo() { ...
AbortController.signal - Web APIs
var controller = new abortcontroller(); var signal = controller.signal; var downloadbtn = document.queryselector('.download'); var abortbtn = document.queryselector('.abort'); downloadbtn.addeventlistener('click', fetchvideo); abortbtn.addeventlistener('click', function() { controller.abort(); console.log('download aborted'); }); function fetchvideo() { ...
AbortController - Web APIs
var controller = new abortcontroller(); var signal = controller.signal; var downloadbtn = document.queryselector('.download'); var abortbtn = document.queryselector('.abort'); downloadbtn.addeventlistener('click', fetchvideo); abortbtn.addeventlistener('click', function() { controller.abort(); console.log('download aborted'); }); function fetchvideo() { ...
AbortSignal: abort event - Web APIs
you can use the abort event in an addeventlistener method: var controller = new abortcontroller(); var signal = controller.signal; signal.addeventlistener('abort', function() { console.log('request aborted'); }; or use the onabort event handler property: var controller = new abortcontroller(); var signal = controller.signal; signal.onabort = function() { console.log('request aborted'); }; specifications specification status...
Accelerometer.x - Web APIs
WebAPIAccelerometerx
let accelerometer = new accelerometer({frequency: 60}); accelerometer.addeventlistener('reading', e => { console.log("acceleration along the x-axis " + accelerometer.x); console.log("acceleration along the y-axis " + accelerometer.y); console.log("acceleration along the z-axis " + accelerometer.z); }); accelerometer.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Accelerometer.y - Web APIs
WebAPIAccelerometery
let accelerometer = new accelerometer({frequency: 60}); accelerometer.addeventlistener('reading', e => { console.log("acceleration along the x-axis " + accelerometer.x); console.log("acceleration along the y-axis " + accelerometer.y); console.log("acceleration along the z-axis " + accelerometer.z); }); accelerometer.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Accelerometer.z - Web APIs
WebAPIAccelerometerz
let accelerometer = new accelerometer({frequency: 60}); accelerometer.addeventlistener('reading', e => { console.log("acceleration along the x-axis " + accelerometer.x); console.log("acceleration along the y-axis " + accelerometer.y); console.log("acceleration along the z-axis " + accelerometer.z); }); accelerometer.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Accelerometer - Web APIs
let acl = new accelerometer({frequency: 60}); acl.addeventlistener('reading', () => { console.log("acceleration along the x-axis " + acl.x); console.log("acceleration along the y-axis " + acl.y); console.log("acceleration along the z-axis " + acl.z); }); acl.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
AddressErrors - Web APIs
window.addeventlistener("load", function(ev) { document.getelementbyid("pay").addeventlistener("click", process, false); }, false); see addeventlistener() for information about event handlers and how they work.
Animation.commitStyles() - Web APIs
examples const divelem = document.queryselector('div'); document.body.addeventlistener('mousemove', evt => { let anim = divelem.animate( { transform: `translate(${ evt.clientx}px, ${evt.clienty}px)` }, { duration: 500, fill: 'forwards' } ); anim.commitstyles(); }); specifications specification status comment web animationsthe definition of 'commitstyles()' in that specification.
Animation.finish() - Web APIs
WebAPIAnimationfinish
interfaceelement.addeventlistener("mousedown", function() { try { player.finish(); } catch(e if e instanceof invalidstate) { console.log("finish() called on paused or finished animation."); } catch(e); logmyerrors(e); //pass exception object to error handler } }); the following example finishes all the animations on a single element, regardless of their direction of playback.
Animation.onremove - Web APIs
examples in our simple replace indefinite animations demo, you can see the following code: const divelem = document.queryselector('div'); document.body.addeventlistener('mousemove', evt => { let anim = divelem.animate( { transform: `translate(${ evt.clientx}px, ${evt.clienty}px)` }, { duration: 500, fill: 'forwards' } ); anim.commitstyles(); //anim.persist() anim.onremove = function() { console.log('animation removed'); } console.log(anim.replacestate); }); here we have a <div> element, and an event listener that fires the event ha...
Animation.pause() - Web APIs
WebAPIAnimationpause
cake.addeventlistener("mouseup", stopplayingalice, false); bottle.addeventlistener("mouseup", stopplayingalice, false); specifications specification status comment web animationsthe definition of 'play()' in that specification.
Animation.persist() - Web APIs
WebAPIAnimationpersist
examples in our simple replace indefinite animations demo, you can see the following code: const divelem = document.queryselector('div'); document.body.addeventlistener('mousemove', evt => { let anim = divelem.animate( { transform: `translate(${ evt.clientx}px, ${evt.clienty}px)` }, { duration: 500, fill: 'forwards' } ); anim.commitstyles(); //anim.persist() anim.onremove = function() { console.log('animation removed'); } console.log(anim.replacestate); }); here we have a <div> element, and an event listener that fires the event ha...
Animation.play() - Web APIs
WebAPIAnimationplay
cake.addeventlistener("mousedown", growalice, false); cake.addeventlistener("touchstart", growalice, false); specifications specification status comment web animationsthe definition of 'play()' in that specification.
Animation.replaceState - Web APIs
examples in our simple replace indefinite animations demo, you can see the following code: const divelem = document.queryselector('div'); document.body.addeventlistener('mousemove', evt => { let anim = divelem.animate( { transform: `translate(${ evt.clientx}px, ${evt.clienty}px)` }, { duration: 500, fill: 'forwards' } ); anim.commitstyles(); //anim.persist() anim.onremove = function() { console.log('animation removed'); } console.log(anim.replacestate); }); here we have a <div> element, and an event listener that fires the event ha...
Animation.updatePlaybackRate() - Web APIs
examples a speed selector component would benefit from smooth updating of updateplaybackrate(), as demonstrated below: speedselector.addeventlistener('input', evt => { cartoon.updateplaybackrate(parsefloat(evt.target.value)); cartoon.ready.then(() => { console.log(`playback rate set to ${cartoon.playbackrate}`); }); }); specifications specification status comment web animationsthe definition of 'updateplaybackrate()' in that specification.
Attr.localName - Web APIs
WebAPIAttrlocalName
html content <button id="example">click me</button> javascript content const element = document.queryselector("#example"); element.addeventlistener("click", function() { const attribute = element.attributes[0]; alert(attribute.localname); }); notes the local name of an attribute is the part of the attribute's qualified name that comes after the colon.
AudioContext.createMediaStreamDestination() - Web APIs
opus file </p> <button>make sine wave</button> <audio controls></audio> <script> var b = document.queryselector("button"); var clicked = false; var chunks = []; var ac = new audiocontext(); var osc = ac.createoscillator(); var dest = ac.createmediastreamdestination(); var mediarecorder = new mediarecorder(dest.stream); osc.connect(dest); b.addeventlistener("click", function(e) { if (!clicked) { mediarecorder.start(); osc.start(0); e.target.innerhtml = "stop recording"; clicked = true; } else { mediarecorder.stop(); osc.stop(0); e.target.disabled = true; } }); mediarecorder.ondataavailable = function(evt) { // push each chunk (blob...
AudioContext.getOutputTimestamp() - Web APIs
play.addeventlistener('click', () => { if(!audioctx) { audioctx = new window.audiocontext(); } getdata(); source.start(0); play.setattribute('disabled', 'disabled'); raf = requestanimationframe(outputtimestamps); }); stop.addeventlistener('click', () => { source.stop(0); play.removeattribute('disabled'); cancelanimationframe(raf); }); // function to output timestamps function outputtimestamp...
AudioScheduledSourceNode: ended event - Web APIs
examples in this simple example, an event listener for the ended event is set up to enable a "start" button in the user interface when the node stops playing: node.addeventlistener('ended', () => { document.getelementbyid("startbutton").disabled = false; }) you can also set up the event handler using the audioscheduledsourcenode.onended property: node.onended = function() { document.getelementbyid("startbutton").disabled = false; } for an example of the ended event in use, see our audio-buffer example on github.
AudioScheduledSourceNode - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: ended fired when the source node has stopped playing, either because it's reached a predetermined stop time, the full duration of the audio has been performed, or because the entire buffer has been played.
AudioTrackList: addtrack event - Web APIs
bubbles no cancelable no interface trackevent event handler property onaddtrack examples using addeventlistener(): const videoelement = document.queryselector('video'); videoelement.audiotracks.addeventlistener('addtrack', (event) => { console.log(`audio track: ${event.track.label} added`); }); using the onaddtrack event handler property: const videoelement = document.queryselector('video'); videoelement.audiotracks.onaddtrack = (event) => { console.log(`audio track: ${event.track.label} added`); }; specifications specification status html living standardthe definition of 'addtrack' in that specification.
AudioTrackList.onaddtrack - Web APIs
note: you can also add a handler for the addtrack event using addeventlistener().
AudioTrackList.onchange - Web APIs
note: you can also add a handler for the change event using addeventlistener().
AudioTrackList.onremovetrack - Web APIs
note: you can also add a handler for the removetrack event using addeventlistener().
AudioTrackList: removetrack event - Web APIs
bubbles no cancelable no interface trackevent event handler property onremovetrack examples using addeventlistener(): const videoelement = document.queryselector('video'); videoelement.audiotracks.addeventlistener('removetrack', (event) => { console.log(`audio track: ${event.track.label} removed`); }); using the onremovetrack event handler property: const videoelement = document.queryselector('video'); videoelement.audiotracks.onremovetrack = (event) => { console.log(`audio track: ${event.track.label} removed`); }; specifications specification status html living standardthe definition of 'removetrack' in that specification.
Background Tasks API - Web APIs
on decodetechnostuff() { totaltaskcount = 0; currenttasknumber = 0; updatedisplay(); let n = getrandomintinclusive(100, 200); for (i=0; i<n; i++) { let taskdata = { count: getrandomintinclusive(75, 150), text: "this text is from task number " + (i+1).tostring() + " of " + n }; enqueuetask(logtaskhandler, taskdata); } } document.getelementbyid("startbutton").addeventlistener("click", decodetechnostuff, false); decodetechnostuff() starts by zeroing the values of totaltaskcount (the number of tasks added to the queue so far) and currenttasknumber (the task currently being run), and then calls updatedisplay() to reset the display to its "nothing's happened yet" state.
BatteryManager - Web APIs
methods inherited from eventtarget: eventtarget.addeventlistener() registers an event handler of a specific event type on the eventtarget.
BeforeInstallPromptEvent.prompt() - Web APIs
example var istoosoon = true; window.addeventlistener("beforeinstallprompt", function(e) { if (istoosoon) { e.preventdefault(); // prevents prompt display // prompt later instead: settimeout(function() { istoosoon = false; e.prompt(); // throws if called more than once or default not prevented }, 10000); } // the event was re-dispatched in response to our request // ...
BeforeInstallPromptEvent - Web APIs
example window.addeventlistener("beforeinstallprompt", function(e) { // log the platforms provided as options in an install prompt console.log(e.platforms); // e.g., ["web", "android", "windows"] e.userchoice.then(function(choiceresult) { console.log(choiceresult.outcome); // either "accepted" or "dismissed" }, handleerror); }); ...
Blob - Web APIs
WebAPIBlob
the following code reads the content of a blob as a typed array: const reader = new filereader(); reader.addeventlistener('loadend', () => { // reader.result contains the contents of blob as a typed array }); reader.readasarraybuffer(blob); another way to read content from a blob is to use a response.
BluetoothCharacteristicProperties - Web APIs
let device = await navigator.bluetooth.requestdevice({ filters: [{services: ['heart_rate']}] }); let gatt = await device.gatt.connect(); let service = await gatt.getprimaryservice('heart_rate'); let characteristic = await service.getcharacteristic('heart_rate_measurement'); if (characteristic.properties.notify) { characteristics.addeventlistener('characteristicvaluechanged', function(event) { console.log(`received heart rate measurement: ${event.target.value}`); } await characteristic.startnotifications(); } specifications specification status comment web bluetooththe definition of 'bluetoothcharacteristicproperties' in that specification.
BroadcastChannel: messageerror event - Web APIs
bubbles no cancelable no interface messageevent event handler property onmessageerror examples this code uses addeventlistener to listen for messages and errors: const channel = new broadcastchannel('example-channel'); channel.addeventlistener('message', (event) => { received.textcontent = event.data; }); channel.addeventlistener('messageerror', (event) => { console.error(event); }); the same, but using the onmessage and onmessageerror event handler properties: const channel = new broadcastchannel('example-channel'); channel.onmessage = (event) => { received.textcontent = event.data; }; channel.onmessageerror =...
CSSPseudoElement - Web APIs
methods csspseudoelement extends eventtarget, so it inherits the following methods: eventtarget.addeventlistener() registers an event handler of a specific event type on the pseudo-element.
CSSStyleDeclaration.setProperty() - Web APIs
randomborder() { const newborder = random(1, 50) + 'px solid ' + randomcolor(); boxpararule.style.setproperty('border', newborder); } function setrandombgcolor() { const newbgcolor = randomcolor(); boxpararule.style.setproperty('background-color', newbgcolor); } function setrandomcolor() { const newcolor = randomcolor(); boxpararule.style.setproperty('color', newcolor); } borderbtn.addeventlistener('click', setrandomborder); bgcolorbtn.addeventlistener('click', setrandombgcolor); colorbtn.addeventlistener('click', setrandomcolor); result specifications specification status comment css object model (cssom)the definition of 'cssstyledeclaration.setproperty()' in that specification.
Managing screen orientation - Web APIs
screen.addeventlistener("orientationchange", function () { console.log("the orientation of the screen is: " + screen.orientation); }); preventing orientation change any web application can lock the screen to suits its own needs.
Cache.add() - Web APIs
WebAPICacheadd
this.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.add('/sw-test/index.html'); }) ); }); specifications specification status comment service workersthe definition of 'cache: add' in that specification.
Cache.addAll() - Web APIs
WebAPICacheaddAll
this.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.addall([ '/sw-test/', '/sw-test/index.html', '/sw-test/style.css', '/sw-test/app.js', '/sw-test/image-list.js', '/sw-test/star-wars-logo.jpg', '/sw-test/gallery/', '/sw-test/gallery/bountyhunters.jpg', '/sw-test/gal...
Cache.match() - Web APIs
WebAPICachematch
self.addeventlistener('fetch', function(event) { // we only want to call event.respondwith() if this is a get request for an html document.
CacheStorage.delete() - Web APIs
this.addeventlistener('activate', function(event) { var cachestokeep = ['v2']; event.waituntil( caches.keys().then(function(keylist) { return promise.all(keylist.map(function(key) { if (cachestokeep.indexof(key) === -1) { return caches.delete(key); } })); }) ); }); specifications specification status comment service workersthe definition of...
CacheStorage.keys() - Web APIs
WebAPICacheStoragekeys
then.addeventlistener('activate', function(event) { var cachewhitelist = ['v2']; event.waituntil( caches.keys().then(function(keylist) { return promise.all(keylist.map(function(key) { if (cachewhitelist.indexof(key) === -1) { return caches.delete(key); } }); }) ); }); specifications specification status comment service workersthe definition...
CacheStorage.match() - Web APIs
self.addeventlistener('fetch', function(event) { event.respondwith(caches.match(event.request).then(function(response) { // caches.match() always resolves // but in case of success response will have value if (response !== undefined) { return response; } else { return fetch(event.request).then(function (response) { // response may be used only once // we need to save clone...
CacheStorage.open() - Web APIs
WebAPICacheStorageopen
self.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.addall([ '/sw-test/', '/sw-test/index.html', '/sw-test/style.css', '/sw-test/app.js', '/sw-test/image-list.js', '/sw-test/star-wars-logo.jpg', '/sw-test/gallery/bountyhunters.jpg', '/sw-test/gallery/mylittlevader.jpg', ...
CanvasPattern.setTransform() - Web APIs
nvas'); var ctx = canvas.getcontext('2d'); var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var edit = document.getelementbyid('edit'); var code = textarea.value; var svg1 = document.getelementbyid('svg1'); var matrix = svg1.createsvgmatrix(); function drawcanvas() { ctx.clearrect(0, 0, canvas.width, canvas.height); eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; drawcanvas(); }); edit.addeventlistener('click', function() { textarea.focus(); }) textarea.addeventlistener('input', drawcanvas); window.addeventlistener('load', drawcanvas); specifications specification status comment html living standardthe definition of 'canvaspattern.settransform' in that specification.
CanvasRenderingContext2D.drawFocusIfNeeded() - Web APIs
html <canvas id="canvas"> <button id="button1">continue</button> <button id="button2">quit</button> </canvas> javascript const canvas = document.getelementbyid('canvas'); const ctx = canvas.getcontext('2d'); const button1 = document.getelementbyid('button1'); const button2 = document.getelementbyid('button2'); document.addeventlistener('focus', redraw, true); document.addeventlistener('blur', redraw, true); canvas.addeventlistener('click', handleclick, false); redraw(); function redraw() { ctx.clearrect(0, 0, canvas.width, canvas.height); drawbutton(button1, 20, 20); drawbutton(button2, 20, 80); } function handleclick(e) { // calculate click coordinates const x = e.clientx - canvas.offsetleft; const y = e.clienty ...
CanvasRenderingContext2D.drawImage() - Web APIs
const canvas = document.getelementbyid('canvas'); const ctx = canvas.getcontext('2d'); const image = document.getelementbyid('source'); image.addeventlistener('load', e => { ctx.drawimage(image, 33, 71, 104, 124, 21, 20, 87, 104); }); result understanding source element size the drawimage() method uses the source element's intrinsic size in css pixels when drawing.
CanvasRenderingContext2D.filter - Web APIs
html <canvas id="canvas"></canvas> <div style="display:none;"> <img id="source" src="https://udn.realityripple.com/samples/90/a34a525ace.jpg"> </div> javascript const canvas = document.getelementbyid('canvas'); const ctx = canvas.getcontext('2d'); const image = document.getelementbyid('source'); image.addeventlistener('load', e => { ctx.filter = 'contrast(1.4) sepia(1) drop-shadow(9px 9px 2px #e81)'; ctx.drawimage(image, 10, 10, 180, 120); }); result specifications specification status comment html living standardthe definition of 'canvasrenderingcontext2d.filter' in that specification.
CanvasRenderingContext2D.isPointInPath() - Web APIs
html <canvas id="canvas"></canvas> javascript const canvas = document.getelementbyid('canvas'); const ctx = canvas.getcontext('2d'); // create circle const circle = new path2d(); circle.arc(150, 75, 50, 0, 2 * math.pi); ctx.fillstyle = 'red'; ctx.fill(circle); // listen for mouse moves canvas.addeventlistener('mousemove', function(event) { // check whether point is inside circle if (ctx.ispointinpath(circle, event.offsetx, event.offsety)) { ctx.fillstyle = 'green'; } else { ctx.fillstyle = 'red'; } // draw circle ctx.clearrect(0, 0, canvas.width, canvas.height); ctx.fill(circle); }); result specifications specification status comment html living s...
CanvasRenderingContext2D.isPointInStroke() - Web APIs
html <canvas id="canvas"></canvas> javascript const canvas = document.getelementbyid('canvas'); const ctx = canvas.getcontext('2d'); // create ellipse const ellipse = new path2d(); ellipse.ellipse(150, 75, 40, 60, math.pi * .25, 0, 2 * math.pi); ctx.linewidth = 25; ctx.strokestyle = 'red'; ctx.fill(ellipse); ctx.stroke(ellipse); // listen for mouse moves canvas.addeventlistener('mousemove', function(event) { // check whether point is inside ellipse's stroke if (ctx.ispointinstroke(ellipse, event.offsetx, event.offsety)) { ctx.strokestyle = 'green'; } else { ctx.strokestyle = 'red'; } // draw ellipse ctx.clearrect(0, 0, canvas.width, canvas.height); ctx.fill(ellipse); ctx.stroke(ellipse); }); result specifications specification ...
CanvasRenderingContext2D.miterLimit - Web APIs
eto(100, 100); ctx.stroke();</textarea> var canvas = document.getelementbyid("canvas"); var ctx = canvas.getcontext("2d"); var textarea = document.getelementbyid("code"); var reset = document.getelementbyid("reset"); var edit = document.getelementbyid("edit"); var code = textarea.value; function drawcanvas() { ctx.clearrect(0, 0, canvas.width, canvas.height); eval(textarea.value); } reset.addeventlistener("click", function() { textarea.value = code; drawcanvas(); }); edit.addeventlistener("click", function() { textarea.focus(); }) textarea.addeventlistener("input", drawcanvas); window.addeventlistener("load", drawcanvas); screenshotlive sample specifications specification status comment html living standardthe definition of 'canvasrenderingcontext2d.miterlimit'...
CanvasRenderingContext2D.scrollPathIntoView() - Web APIs
); ctx.scrollpathintoview();</textarea> var canvas = document.getelementbyid("canvas"); var ctx = canvas.getcontext("2d"); var textarea = document.getelementbyid("code"); var reset = document.getelementbyid("reset"); var edit = document.getelementbyid("edit"); var code = textarea.value; function drawcanvas() { ctx.clearrect(0, 0, canvas.width, canvas.height); eval(textarea.value); } reset.addeventlistener("click", function() { textarea.value = code; drawcanvas(); }); edit.addeventlistener("click", function() { textarea.focus(); }) textarea.addeventlistener("input", drawcanvas); window.addeventlistener("load", drawcanvas); specifications specification status comment html living standardthe definition of 'canvasrenderingcontext2d.scrollpathintoview' in that spec...
Drawing text - Web APIs
text("hello world", 0, 100);</textarea> var canvas = document.getelementbyid('canvas'); var ctx = canvas.getcontext('2d'); var textarea = document.getelementbyid('code'); var reset = document.getelementbyid('reset'); var edit = document.getelementbyid('edit'); var code = textarea.value; function drawcanvas() { ctx.clearrect(0, 0, canvas.width, canvas.height); eval(textarea.value); } reset.addeventlistener('click', function() { textarea.value = code; drawcanvas(); }); edit.addeventlistener('click', function() { textarea.focus(); }) textarea.addeventlistener('input', drawcanvas); window.addeventlistener('load', drawcanvas); advanced text measurements in the case you need to obtain more details about the text, the following method allows you to measure it.
Hit regions and accessibility - Web APIs
<canvas id="canvas"></canvas> <script> var canvas = document.getelementbyid('canvas'); var ctx = canvas.getcontext('2d'); ctx.beginpath(); ctx.arc(70, 80, 10, 0, 2 * math.pi, false); ctx.fill(); ctx.addhitregion({id: 'circle'}); canvas.addeventlistener('mousemove', function(event) { if (event.region) { alert('hit region: ' + event.region); } }); </script> the addhitregion() method also takes a control option to route events to an element (that is a descendant of the canvas): ctx.addhitregion({control: element}); this can be useful for routing to <input> elements, for example.
Using images - Web APIs
so you need to be sure to use the load event so you don't try this before the image has loaded: var img = new image(); // create new img element img.addeventlistener('load', function() { // execute drawimage statements here }, false); img.src = 'myimage.png'; // set source path if you're only using one external image this can be a good approach, but once you need to track more than one we need to resort to something more clever.
Client.type - Web APIs
WebAPIClienttype
a document) function sendmessage(message) { return new promise(function(resolve, reject) { // note that this is the serviceworker.postmessage version navigator.serviceworker.controller.postmessage(message); window.serviceworker.onmessage = function(e) { resolve(e.data); }; }); } // controlling service worker self.addeventlistener("message", function(e) { // e.source is a client object e.source.postmessage("hello!
Client.url - Web APIs
WebAPIClienturl
example self.addeventlistener('notificationclick', function(event) { console.log('on notification click: ', event.notification.tag); event.notification.close(); // this looks to see if the current is already open and // focuses if it is event.waituntil(clients.matchall({ type: 'window' }).then(function(clientlist) { for (var i = 0; i < clientlist.length; i++) { var client = clientlist[i]; if (client.url == '/' && 'focus' in client) return client.focus(); } if (clients.openwindow) return clients.openwindow('/'); })); }); specifications specification status comment ...
Clients.claim() - Web APIs
WebAPIClientsclaim
self.addeventlistener('activate', event => { event.waituntil(clients.claim()); }); specifications specification status comment service workersthe definition of 'claim()' in that specification.
Clients.openWindow() - Web APIs
send notification to os if applicable if (self.notification.permission === 'granted') { const notificationobject = { body: 'click here to view your messages.', data: { url: self.location.origin + '/some/path' }, // data: { url: 'http://example.com' }, }; self.registration.shownotification('you\'ve got messages!', notificationobject); } // notification click event listener self.addeventlistener('notificationclick', e => { // close the notification popout e.notification.close(); // get all the window clients e.waituntil(clients.matchall({ type: 'window' }).then(clientsarr => { // if a window tab matching the targeted url already exists, focus that; const hadwindowtofocus = clientsarr.some(windowclient => windowclient.url === e.notification.data.url ?
Clients - Web APIs
WebAPIClients
addeventlistener('notificationclick', event => { event.waituntil(async function() { const allclients = await clients.matchall({ includeuncontrolled: true }); let chatclient; // let's see if we already have a chat window open: for (const client of allclients) { const url = new url(client.url); if (url.pathname == '/chat/') { // excellent, let's use it!
Constraint validation API - Web APIs
if you wanted to instead display custom error messages, you could use javascript like the following: const nameinput = document.queryselector('input'); const form = document.queryselector('form'); nameinput.addeventlistener('input', () => { nameinput.setcustomvalidity(''); nameinput.checkvalidity(); }); nameinput.addeventlistener('invalid', () => { if(nameinput.value === '') { nameinput.setcustomvalidity('enter your username!'); } else { nameinput.setcustomvalidity('usernames can only contain upper and lowercase letters.
ContentIndexEvent.id - Web APIs
self.addeventlistener('contentdelete', (event) => { console.log(event.id); // logs content index id, which can then be used to determine what content to delete from your cache }); specifications specification status comment unknownthe definition of 'id' in that specification.
ContentIndexEvent - Web APIs
self.addeventlistener('contentdelete', (event) => { console.log(event.id); // logs content index id, which can then be used to determine what content to delete from your cache }); specifications specification status comment unknownthe definition of 'contentindexevent' in that specification.
Content Index API - Web APIs
self.addeventlistener('contentdelete', (event) => { console.log(event.id); // logs content index id, which can then be used to determine what content to delete from your cache }); the contentdelete event is only fired when the deletion happens due to interaction with the browser's built-in user interface.
CustomEvent() - Web APIs
example // add an appropriate event listener obj.addeventlistener("cat", function(e) { process(e.detail) }); // create and dispatch the event var event = new customevent("cat", { detail: { hazcheeseburger: true } }); obj.dispatchevent(event); additional examples can be found at creating and triggering events.
CustomEvent.detail - Web APIs
example // add an appropriate event listener obj.addeventlistener("cat", function(e) { process(e.detail) }); // create and dispatch the event let event = new customevent("cat", { detail: { hazcheeseburger: true } }); obj.dispatchevent(event); // will return an object contaning the hazcheeseburger property let mydetail = event.detail; specifications specification status comment domthe definition of 'detail' in that specification.
DOMTokenList.toggle() - Web APIs
first, the html: <span class="a b">classlist is 'a b'</span> now the javascript: let span = document.queryselector("span"); let classes = span.classlist; span.addeventlistener('click', function() { let result = classes.toggle("c"); if (result) { span.textcontent = `'c' added; classlist is now "${classes}".`; } else { span.textcontent = `'c' removed; classlist is now "${classes}".`; } }) the output looks like this: specifications specification status comment domthe definition of 'toggle()' in that specification.
DataTransferItem.webkitGetAsEntry() - Web APIs
first, we prevent the dragover event from being handled by the default handler, so that our drop zone can receive the drop: dropzone.addeventlistener("dragover", function(event) { event.preventdefault(); }, false); the event handler that kicks everything off, of course, is the handler for the drop event: dropzone.addeventlistener("drop", function(event) { let items = event.datatransfer.items; event.preventdefault(); listing.innerhtml = ""; for (let i=0; i<items.length; i++) { let item = items[i].webkitgetasentry(); if...
DedicatedWorkerGlobalScope: message event - Web APIs
bubbles no cancelable no interface messageevent event handler property onmessage examples this code creates a new worker and sends it a message using worker.postmessage(): const worker = new worker("static/scripts/worker.js"); worker.addeventlistener('message', (event) => { console.log(`received message from worker: ${event.data}`) }); the worker can listen for this message using addeventlistener(): // inside static/scripts/worker.js self.addeventlistener('message', (event) => { console.log(`received message from parent: ${event.data}`); }); alternatively, it could listen using the onmessage event handler property: // static/sc...
DedicatedWorkerGlobalScope: messageerror event - Web APIs
bubbles no cancelable no interface messageevent event handler property onmessageerror examples listen for messageerror using addeventlistener(): // inside worker.js self.addeventlistener('messageerror', (event) => { self.postmessage('error receiving message'); console.error(event); }); the same, but using the onmessageerror event handler property: // inside worker.js self.onmessageerror = (event) => { self.postmessage('error receiving message'); console.error(event); }; specifications specification status html living standard living standard ...
DeviceLightEvent - Web APIs
example window.addeventlistener('devicelight', function(event) { console.log(event.value); }); specifications no specification.
DeviceMotionEvent - Web APIs
example window.addeventlistener('devicemotion', function(event) { console.log(event.acceleration.x + ' m/s2'); }); specifications specification status comment deviceorientation event specificationthe definition of 'devicemotionevent' in that specification.
DeviceOrientationEvent - Web APIs
example window.addeventlistener('deviceorientation', function(event) { console.log(event.alpha + ' : ' + event.beta + ' : ' + event.gamma); }); specifications specification status comment deviceorientation event specification editor's draft initial specification.
DeviceProximityEvent - Web APIs
examples window.addeventlistener('deviceproximity', function(event) { console.log("value: " + event.value, "max: " + event.max, "min: " + event.min); }); ...
Document: animationcancel event - Web APIs
document.addeventlistener('animationcancel', () => { console.log('animation canceled'); }); the same, but using the onanimationcancel property instead of addeventlistener(): document.onanimationcancel = () => { console.log('animation canceled'); }; see a live example of this event.
Document: animationend event - Web APIs
examples this example listens for the animationend event: document.addeventlistener('animationend', () => { console.log('animation ended'); }); the same, but using the onanimationend event handler property: document.onanimationend = () => { console.log('animation ended'); }; see a live example of this event.
Document: animationiteration event - Web APIs
examples this code uses animationiteration to keep track of the number of iterations an animation has completed: let iterationcount = 0; document.addeventlistener('animationiteration', () => { iterationcount++; console.log(`animation iteration count: ${iterationcount}`); }); the same, but using the onanimationiteration event handler property: let iterationcount = 0; document.onanimationiteration = () => { iterationcount++; console.log(`animation iteration count: ${iterationcount}`); }; see a live example of this event.
Document: animationstart event - Web APIs
examples this listens for the animationstart event and logs a message when it is fired: document.addeventlistener('animationstart', () => { console.log('animation started'); }); the same, but using onanimationstart: document.onanimationstart = () => { console.log('animation started'); }; see a live example of this event.
Document.caretRangeFromPoint() - Web APIs
range.startcontainer; offset = range.startoffset; } // only split text_nodes if (textnode && textnode.nodetype == 3) { let replacement = textnode.splittext(offset); let br = document.createelement('br'); textnode.parentnode.insertbefore(br, replacement); } } let paragraphs = document.getelementsbytagname("p"); for (let i = 0; i < paragraphs.length; i++) { paragraphs[i].addeventlistener('click', insertbreakatpoint, false); } result ...
Document: copy event - Web APIs
examples document.addeventlistener('copy', (event) => { console.log('copy action initiated') }); specifications specification status clipboard api and events working draft ...
Document.createEvent() - Web APIs
elem.addeventlistener('build', function (e) { // e.target matches elem }, false); // target can be any element or other eventtarget.
Document: cut event - Web APIs
examples document.addeventlistener('cut', (event) => { console.log('cut action initiated') }); specifications specification status clipboard api and events working draft ...
Document: fullscreenchange event - Web APIs
document.addeventlistener('fullscreenchange', (event) => { // document.fullscreenelement will point to the element that // is in fullscreen mode if there is one.
Document: fullscreenerror event - Web APIs
examples const requestor = document.queryselector('div'); document.addeventlistener('fullscreenerror', (event) => { console.error('an error occurred changing into fullscreen'); console.log(event); }); requestor.requestfullscreen(); specifications specification status fullscreen api living standard ...
Document: gotpointercapture event - Web APIs
const para = document.queryselector('p'); document.addeventlistener('gotpointercapture', () => { console.log('i\'ve been captured!') }); para.addeventlistener('pointerdown', (event) => { para.setpointercapture(event.pointerid); }); the same example, using the ongotpointercapture event handler property: const para = document.queryselector('p'); document.ongotpointercapture = () => { console.log('i\'ve been captured!') }; para.addeventlistener('pointerd...
Document.hidden - Web APIs
WebAPIDocumenthidden
syntax var boolean = document.hidden examples document.addeventlistener("visibilitychange", function() { console.log( document.hidden ); // modify behavior...
Document: lostpointercapture event - Web APIs
const para = document.queryselector('p'); document.addeventlistener('lostpointercapture', () => { console.log('i\'ve been released!') }); para.addeventlistener('pointerdown', (event) => { para.setpointercapture(event.pointerid); }); the same example, but using the onlostpointercapture event handler property: const para = document.queryselector('p'); document.onlostpointercapture = () => { console.log('i\'ve been released!') }; para.addeventlistener('p...
Document.onafterscriptexecute - Web APIs
example function finished(e) { logmessage(`finished script with id: ${e.target.id}`); } document.addeventlistener('afterscriptexecute', finished, true); view live example specification html5 ...
Document.onbeforescriptexecute - Web APIs
example function starting(e) { logmessage("starting script with id: " + e.target.id); } document.addeventlistener("beforescriptexecute", starting, true); view live examples specification html5 ...
Document.ononline - Web APIs
WebAPIDocumentononline
you can register listeners for these events in a few familiar ways: using addeventlistener on the window, document, or document.body by setting the .ononline or .onoffline properties on document or document.body to a javascript function object.
Document: paste event - Web APIs
examples document.addeventlistener('paste', (event) => { console.log('paste action initiated') }); specifications specification status clipboard api and events working draft ...
Document: pointercancel event - Web APIs
examples using addeventlistener(): document.addeventlistener('pointercancel', (event) => { console.log('pointer event cancelled') }); using the onpointercancel event handler property: document.onpointercancel = (event) => { console.log('pointer event cancelled') }; specifications specification status pointer events obsolete ...
Document: pointerdown event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerdown examples using addeventlistener(): document.addeventlistener('pointerdown', (event) => { console.log('pointer down event'); }); using the onpointerdown event handler property: document.onpointerdown = (event) => { console.log('pointer down event'); }; specifications specification status pointer events obsolete ...
Document: pointerenter event - Web APIs
bubbles no cancelable no interface pointerevent event handler property onpointerenter examples using addeventlistener(): document.addeventlistener('pointerenter', (event) => { console.log('pointer entered element'); }); using the onpointerenter event handler property: document.onpointerenter = (event) => { console.log('pointer entered element'); }; specifications specification status pointer events obsolete ...
Document: pointerleave event - Web APIs
bubbles no cancelable no interface pointerevent event handler property onpointerleave examples using addeventlistener(): document.addeventlistener('pointerleave', (event) => { console.log('pointer left element'); }); using the onpointerleave event handler property: document.onpointerleave = (event) => { console.log('pointer left element'); }; specifications specification status pointer events obsolete ...
Document: pointerlockchange event - Web APIs
bubbles yes cancelable no interface event event handler property onpointerlockchange examples using addeventlistener(): document.addeventlistener('pointerlockchange', (event) => { console.log('pointer lock changed'); }); using the onpointerlockchange event handler property: document.onpointerlockchange = (event) => { console.log('pointer lock changed'); }; specifications specification status pointer lock candidate recommendation ...
Document: pointerlockerror event - Web APIs
bubbles yes cancelable no interface event event handler property onpointerlockerror examples using addeventlistener(): const para = document.queryselector('p'); document.addeventlistener('pointerlockerror', (event) => { console.log('error locking pointer'); }); using the onpointerlockerror event handler property: document.onpointerlockerror = (event) => { console.log('error locking pointer'); }; specifications specification status pointer lock candidate recommendation ...
Document: pointermove event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointermove examples using addeventlistener(): document.addeventlistener('pointermove', (event) => { console.log('pointer moved'); }); using the onpointermove event handler property: document.onpointermove = (event) => { console.log('pointer moved'); }; specifications specification status pointer events obsolete ...
Document: pointerout event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerout examples using addeventlistener(): document.addeventlistener('pointerout', (event) => { console.log('pointer moved out'); }); using the onpointerout event handler property: document.onpointerout = (event) => { console.log('pointer moved out'); }; specifications specification status pointer events obsolete ...
Document: pointerover event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerover examples using addeventlistener(): document.addeventlistener('pointerover', (event) => { console.log('pointer moved in'); }); using the onpointerover event handler property: document.onpointerover = (event) => { console.log('pointer moved in'); }; specifications specification status pointer events obsolete ...
Document: pointerup event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerup examples using addeventlistener(): document.addeventlistener('pointerup', (event) => { console.log('pointer up'); }); using the onpointerup event handler property: document.onpointerup = (event) => { console.log('pointer up'); }; specifications specification status pointer events obsolete ...
Document.readyState - Web APIs
statechange = function () { if (document.readystate === 'interactive') { initapplication(); } } readystatechange as an alternative to load event // alternative to load event document.onreadystatechange = function () { if (document.readystate === 'complete') { initapplication(); } } readystatechange as event listener to insert or modify the dom before domcontentloaded document.addeventlistener('readystatechange', event => { if (event.target.readystate === 'interactive') { initloader(); } else if (event.target.readystate === 'complete') { initapp(); } }); specifications specification status comment html living standardthe definition of 'document readiness' in that specification.
Document: readystatechange event - Web APIs
late-areas: "control log"; } .controls { grid-area: control; display: flex; align-items: center; justify-content: center; } .event-log { grid-area: log; } .event-log-contents { resize: none; } label, button { display: block; } #reload { height: 2rem; } js const log = document.queryselector('.event-log-contents'); const reload = document.queryselector('#reload'); reload.addeventlistener('click', () => { log.textcontent =''; window.settimeout(() => { window.location.reload(true); }, 200); }); window.addeventlistener('load', (event) => { log.textcontent = log.textcontent + 'load\n'; }); document.addeventlistener('readystatechange', (event) => { log.textcontent = log.textcontent + `readystate: ${document.readystate}\n`; }); document.addeventlistener('domconte...
Document: scroll event - Web APIs
// reference: http://www.html5rocks.com/en/tutorials/speed/animations/ let last_known_scroll_position = 0; let ticking = false; function dosomething(scroll_pos) { // do something with the scroll position } window.addeventlistener('scroll', function(e) { last_known_scroll_position = window.scrolly; if (!ticking) { window.requestanimationframe(function() { dosomething(last_known_scroll_position); ticking = false; }); ticking = true; } }); see more, similar examples on the resize event page.
Document: selectionchange event - Web APIs
bubbles no cancelable no interface event event handler property onselectionchange examples // addeventlistener version document.addeventlistener('selectionchange', () => { console.log(document.getselection()); }); // onselectionchange version document.onselectionchange = () => { console.log(document.getselection()); }; specifications specification status comment selection apithe definition of 'selectionchange' in that specification.
Document: selectstart event - Web APIs
bubbles yes cancelable yes interface event event handler property onselectstart examples // addeventlistener version document.addeventlistener('selectstart', () => { console.log('selection started'); }); // onselectstart version document.onselectstart = () => { console.log('selection changed.'); }; specifications specification status comment selection apithe definition of 'selectstart' in that specification.
Document: transitioncancel event - Web APIs
examples this code adds a listener to the transitioncancel event: document.addeventlistener('transitioncancel', () => { console.log('transition canceled'); }); the same, but using the ontransitioncancel property instead of addeventlistener(): document.ontransitioncancel = () => { console.log('transition canceled'); }; see a live example of this event.
Document: transitionend event - Web APIs
examples this code adds a listener to the transitionend event: document.addeventlistener('transitionend', () => { console.log('transition ended'); }); the same, but using the ontransitionend property instead of addeventlistener(): document.ontransitionend = () => { console.log('transition ended'); }; see a live example of this event.
Document: transitionrun event - Web APIs
examples this code adds a listener to the transitionrun event: document.addeventlistener('transitionrun', () => { console.log('transition is running but hasn't necessarily started transitioning yet'); }); the same, but using the ontransitionrun property instead of addeventlistener(): document.ontransitionrun = () => { console.log('transition started running'); }; see a live example of this event.
Document: transitionstart event - Web APIs
examples this code adds a listener to the transitionstart event: document.addeventlistener('transitionstart', () => { console.log('started transitioning'); }); the same, but using the ontransitionstart property instead of addeventlistener(): document.ontransitionrun = () => { console.log('started transitioning'); }; see a live example of this event.
Document.visibilityState - Web APIs
syntax var string = document.visibilitystate examples document.addeventlistener("visibilitychange", function() { console.log( document.visibilitystate ); // modify behavior...
Document: visibilitychange event - Web APIs
document.addeventlistener("visibilitychange", function() { if (document.visibilitystate === 'visible') { backgroundmusic.play(); } else { backgroundmusic.pause(); } }); specifications specification status comment page visibility (second edition)the definition of 'visibilitychange' in that specification.
Document: wheel event - Web APIs
m(event) { event.preventdefault(); if (event.deltay < 0) { // zoom in scale *= event.deltay * -2; } else { // zoom out scale /= event.deltay * 2; } // restrict scale scale = math.min(math.max(.125, scale), 4); // apply scale transform el.style.transform = `scale(${scale})`; } let scale = 1; const el = document.queryselector('div'); document.onwheel = zoom; addeventlistener equivalent the event handler can also be set up using the addeventlistener() method: document.addeventlistener('wheel', zoom); specifications specification status comment ui eventsthe definition of 'wheel' in that specification.
Document - Web APIs
WebAPIDocument
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
DocumentOrShadowRoot.activeElement - Web APIs
rea.selectionstart, activetextarea.selectionend ); const outputelement = document.getelementbyid('output-element'); const outputtext = document.getelementbyid('output-text'); outputelement.innerhtml = activetextarea.id; outputtext.innerhtml = selection; } const textarea1 = document.getelementbyid('ta-example-one'); const textarea2 = document.getelementbyid('ta-example-two'); textarea1.addeventlistener('mouseup', onmouseup, false); textarea2.addeventlistener('mouseup', onmouseup, false); result specifications specification status comment html living standardthe definition of 'activeelement' in that specification.
DocumentOrShadowRoot.caretPositionFromPoint() - Web APIs
er; offset = range.startoffset; } // only split text_nodes if (textnode.nodetype == 3) { var replacement = textnode.splittext(offset); var br = document.createelement('br'); textnode.parentnode.insertbefore(br, replacement); } } window.onload = function (){ var paragraphs = document.getelementsbytagname("p"); for (i=0 ; i < paragraphs.length; i++) { paragraphs[i].addeventlistener("click", insertbreakatpoint, false); } }; specifications specification status comment css object model (cssom) view modulethe definition of 'caretpositionfrompoint()' in that specification.
Examples of web and XML development using the DOM - Web APIs
ev.stoppropagation(); alert("event propagation halted."); } function load() { elem = document.getelementbyid("tbl1"); elem.addeventlistener("click", stopevent, false); } </script> </head> <body onload="load();"> <table id="t-daddy" onclick="alert('hi');"> <tr id="tbl1"> <td id="c1">one</td> </tr> <tr> <td id="c2">two</td> </tr> </table> </body> </html> example 6: getcomputedstyle this example demonstrates how the window.getcomputedstyle method can be used to get the styles of an element that are not set using th...
Introduction to the DOM - Web APIs
document.getelementbyid(id) document.getelementsbytagname(name) document.createelement(name) parentnode.appendchild(node) element.innerhtml element.style.left element.setattribute() element.getattribute() element.addeventlistener() window.content window.onload window.scrollto() testing the dom api this document provides samples for every interface that you can use in your own web development.
DragEvent.dataTransfer - Web APIs
} dragtarget.addeventlistener("dragend", function(ev) { // call the drag and drop data processor if (ev.datatransfer !== null) processdata(ev.datatransfer); }, false); specifications specification status comment html living standardthe definition of 'dragevent.datatransfer' in that specification.
Element: MSManipulationStateChanged event - Web APIs
examples // listen for panning state change events outerscroller.addeventlistener("msmanipulationstatechanged", function(e) { // check to see if they lifted while pulled to the top if (e.currentstate == ms_manipulation_state_inertia && outerscroller.scrolltop === 0) { refreshitemsasync(); } }); specifications not part of any specification.
Element: click event - Web APIs
html <button>click</button> javascript const button = document.queryselector('button'); button.addeventlistener('click', event => { button.innerhtml = `click count: ${event.detail}`; }); result try making rapid, repeated clicks on the button to increase the click count.
Element: contextmenu event - Web APIs
html <p id="nocontextmenu">the context menu has been disabled on this paragraph.</p> <p>but it has not been disabled on this one.</p> javascript nocontext = document.getelementbyid('nocontextmenu'); nocontext.addeventlistener('contextmenu', e => { e.preventdefault(); }); result specifications specification status comment html living standardthe definition of 'contextmenu' in that specification.
Element: copy event - Web APIs
ve example html <div class="source" contenteditable="true">try copying text from this box...</div> <div class="target" contenteditable="true">...and pasting it into this one</div> css div.source, div.target { border: 1px solid gray; margin: .5rem; padding: .5rem; height: 1rem; background-color: #e9eef1; } js const source = document.queryselector('div.source'); source.addeventlistener('copy', (event) => { const selection = document.getselection(); event.clipboarddata.setdata('text/plain', selection.tostring().touppercase()); event.preventdefault(); }); result specifications specification status clipboard api and events working draft ...
Element: cut event - Web APIs
WebAPIElementcut event
ve example html <div class="source" contenteditable="true">try cutting text from this box...</div> <div class="target" contenteditable="true">...and pasting it into this one</div> css div.source, div.target { border: 1px solid gray; margin: .5rem; padding: .5rem; height: 1rem; background-color: #e9eef1; } js const source = document.queryselector('div.source'); source.addeventlistener('cut', (event) => { const selection = document.getselection(); event.clipboarddata.setdata('text/plain', selection.tostring().touppercase()); selection.deletefromdocument(); event.preventdefault(); }); result specifications specification status clipboard api and events working draft ...
Element: dblclick event - Web APIs
javascript const card = document.queryselector('aside'); card.addeventlistener('dblclick', function (e) { card.classlist.toggle('large'); }); html <aside> <h3>my card</h3> <p>double click to resize this object.</p> </aside> css aside { background: #fe9; border-radius: 1em; display: inline-block; padding: 1em; transform: scale(.9); transform-origin: 0 0; transition: transform .6s; } .large { transform: scale(1.3); } result specifications ...
Element: error event - Web APIs
area: control; display: flex; align-items: center; justify-content: center; } .event-log { grid-area: log; } .event-log-contents { resize: none; } label, button { display: block; } button { height: 2rem; margin: .5rem; } img { width: 0; height: 0; } js const log = document.queryselector('.event-log-contents'); const badimg = document.queryselector('.bad-img'); badimg.addeventlistener('error', (event) => { log.textcontent = log.textcontent + `${event.type}: loading image\n`; console.log(event) }); const imgerror = document.queryselector('#img-error'); imgerror.addeventlistener('click', () => { badimg.setattribute('src', 'i-dont-exist'); }); result specifications specification status ui events working draft ...
Element: focusin event - Web APIs
bubbles yes cancelable no interface focusevent event handler property onfocusin sync / async sync composed yes examples live example html <form id="form"> <input type="text" placeholder="text input"> <input type="password" placeholder="password"> </form> javascript const form = document.getelementbyid('form'); form.addeventlistener('focusin', (event) => { event.target.style.background = 'pink'; }); form.addeventlistener('focusout', (event) => { event.target.style.background = ''; }); result specifications specification status comment ui events working draft added info that this event is composed.
Element: focusout event - Web APIs
bubbles yes cancelable no interface focusevent event handler property onfocusout sync / async sync composed yes examples live example html <form id="form"> <input type="text" placeholder="text input"> <input type="password" placeholder="password"> </form> javascript const form = document.getelementbyid('form'); form.addeventlistener('focusin', (event) => { event.target.style.background = 'pink'; }); form.addeventlistener('focusout', (event) => { event.target.style.background = ''; }); result specifications specification status comment ui events working draft added info that this event is composed.
Element: fullscreenerror event - Web APIs
examples const requestor = document.queryselector('div'); requestor.addeventlistener('fullscreenerror', (event) => { console.error('an error occurred changing into fullscreen'); console.log(event); }); requestor.requestfullscreen(); specifications specification status fullscreen api living standard ...
Element.innerHTML - Web APIs
WebAPIElementinnerHTML
about mouseevent based events (such as mousedown, click, and mouseenter): function logevent(event) { var msg = "event <strong>" + event.type + "</strong> at <em>" + event.clientx + ", " + event.clienty + "</em>"; log(msg); } then we use this as the event handler for a number of mouse events on the box that contains our log: var boxelem = document.queryselector(".box"); boxelem.addeventlistener("mousedown", logevent); boxelem.addeventlistener("mouseup", logevent); boxelem.addeventlistener("click", logevent); boxelem.addeventlistener("mouseenter", logevent); boxelem.addeventlistener("mouseleave", logevent); html the html is quite simple for our example.
Element.insertAdjacentElement() - Web APIs
example beforebtn.addeventlistener('click', function() { var tempdiv = document.createelement('div'); tempdiv.style.backgroundcolor = randomcolor(); if (activeelem) { activeelem.insertadjacentelement('beforebegin',tempdiv); } setlistener(tempdiv); }); afterbtn.addeventlistener('click', function() { var tempdiv = document.createelement('div'); tempdiv.style.backgroundcolor = randomcolor(); if (activeelem) { ...
Element.insertAdjacentText() - Web APIs
example beforebtn.addeventlistener('click', function() { para.insertadjacenttext('afterbegin',textinput.value); }); afterbtn.addeventlistener('click', function() { para.insertadjacenttext('beforeend',textinput.value); }); have a look at our insertadjacenttext.html demo on github (see the source code too.) here we have a simple paragraph.
Element: mousedown event - Web APIs
// add the event listeners for mousedown, mousemove, and mouseup mypics.addeventlistener('mousedown', e => { x = e.offsetx; y = e.offsety; isdrawing = true; }); mypics.addeventlistener('mousemove', e => { if (isdrawing === true) { drawline(context, x, y, e.offsetx, e.offsety); x = e.offsetx; y = e.offsety; } }); window.addeventlistener('mouseup', e => { if (isdrawing === true) { drawline(context, x, y, e.offsetx, e.offsety); x = 0; y = 0; isd...
Element: mouseenter event - Web APIs
#mousetarget { box-sizing: border-box; width:15rem; border:1px solid #333; } javascript var entereventcount = 0; var leaveeventcount = 0; const mousetarget = document.getelementbyid('mousetarget'); const unorderedlist = document.getelementbyid('unorderedlist'); mousetarget.addeventlistener('mouseenter', e => { mousetarget.style.border = '5px dotted orange'; entereventcount++; addlistitem('this is mouseenter event ' + entereventcount + '.'); }); mousetarget.addeventlistener('mouseleave', e => { mousetarget.style.border = '1px solid #333'; leaveeventcount++; addlistitem('this is mouseleave event ' + leaveeventcount + '.'); }); function addlistitem(text) { // create a ...
Element: mouseleave event - Web APIs
#mousetarget { box-sizing: border-box; width:15rem; border:1px solid #333; } javascript var entereventcount = 0; var leaveeventcount = 0; const mousetarget = document.getelementbyid('mousetarget'); const unorderedlist = document.getelementbyid('unorderedlist'); mousetarget.addeventlistener('mouseenter', e => { mousetarget.style.border = '5px dotted orange'; entereventcount++; addlistitem('this is mouseenter event ' + entereventcount + '.'); }); mousetarget.addeventlistener('mouseleave', e => { mousetarget.style.border = '1px solid #333'; leaveeventcount++; addlistitem('this is mouseleave event ' + leaveeventcount + '.'); }); function addlistitem(text) { // create a ...
Element: mousemove event - Web APIs
// add the event listeners for mousedown, mousemove, and mouseup mypics.addeventlistener('mousedown', e => { x = e.offsetx; y = e.offsety; isdrawing = true; }); mypics.addeventlistener('mousemove', e => { if (isdrawing === true) { drawline(context, x, y, e.offsetx, e.offsety); x = e.offsetx; y = e.offsety; } }); window.addeventlistener('mouseup', e => { if (isdrawing === true) { drawline(context, x, y, e.offsetx, e.offsety); x = 0; y = 0; isd...
Element: mouseout event - Web APIs
html <ul id="test"> <li>item 1</li> <li>item 2</li> <li>item 3</li> </ul> javascript let test = document.getelementbyid("test"); // briefly make the list purple when the mouse moves off the // <ul> element test.addeventlistener("mouseleave", function( event ) { // highlight the mouseleave target event.target.style.color = "purple"; // reset the color after a short delay settimeout(function() { event.target.style.color = ""; }, 1000); }, false); // briefly make an <li> orange when the mouse moves off of it test.addeventlistener("mouseout", function( event ) { // highlight the mouseout target event.tar...
Element: mouseover event - Web APIs
html <ul id="test"> <li>item 1</li> <li>item 2</li> <li>item 3</li> </ul> javascript let test = document.getelementbyid("test"); // this handler will be executed only once when the cursor // moves over the unordered list test.addeventlistener("mouseenter", function( event ) { // highlight the mouseenter target event.target.style.color = "purple"; // reset the color after a short delay settimeout(function() { event.target.style.color = ""; }, 500); }, false); // this handler will be executed every time the cursor // is moved over a different list item test.addeventlistener("mouseover", function( event ) { // highlight...
Element: mouseup event - Web APIs
// add the event listeners for mousedown, mousemove, and mouseup mypics.addeventlistener('mousedown', e => { x = e.offsetx; y = e.offsety; isdrawing = true; }); mypics.addeventlistener('mousemove', e => { if (isdrawing === true) { drawline(context, x, y, e.offsetx, e.offsety); x = e.offsetx; y = e.offsety; } }); window.addeventlistener('mouseup', e => { if (isdrawing === true) { drawline(context, x, y, e.offsetx, e.offsety); x = 0; y = 0; isd...
Element: msContentZoom event - Web APIs
bubbles unknown cancelable unknown interface unknown event handler property unknown example contentzoom.addeventlistener("mscontentzoom", function(e) { zoomfactor.value = contentzoom.mscontentzoomfactor.tofixed(2); }); specifications not part of any specification.
Element: overflow event - Web APIs
tyle> #wrapper { width: 20px; height: 20px; background: #000; padding: 5px; overflow: hidden; } #child { width: 40px; height: 40px; border: 2px solid grey; background: #ccc; } </style> <script> var wrapper = document.getelementbyid("wrapper"), child = document.getelementbyid("child"), toggle = document.getelementbyid("toggle"); wrapper.addeventlistener("overflow", function( event ) { console.log( event ); }, false); wrapper.addeventlistener("underflow", function( event ) { console.log( event ); }, false); toggle.addeventlistener("change", function( event ) { if ( event.target.checked ) { child.style.width = "40px"; child.style.height = "40px"; } else { child.style.width = "10px"; ...
Element.part - Web APIs
WebAPIElementpart
let tabs = []; let children = this.shadowroot.children; for(let elem of children) { if(elem.getattribute('part')) { tabs.push(elem); } } tabs.foreach((tab) => { tab.addeventlistener('click', (e) => { tabs.foreach((tab) => { tab.part = 'tab'; }) e.target.part = 'tab active'; }) console.log(tab.part); }) specifications specification status comment shadow partsthe definition of 'element.part' in that specification.
Element: paste event - Web APIs
ve example html <div class="source" contenteditable="true">try copying text from this box...</div> <div class="target" contenteditable="true">...and pasting it into this one</div> css div.source, div.target { border: 1px solid gray; margin: .5rem; padding: .5rem; height: 1rem; background-color: #e9eef1; } js const target = document.queryselector('div.target'); target.addeventlistener('paste', (event) => { let paste = (event.clipboarddata || window.clipboarddata).getdata('text'); paste = paste.touppercase(); const selection = window.getselection(); if (!selection.rangecount) return false; selection.deletefromdocument(); selection.getrangeat(0).insertnode(document.createtextnode(paste)); event.preventdefault(); }); result specifications ...
Element.scrollWidth - Web APIs
yid('anotherdiv'); //check to determine if an overflow is happening function isoverflowing(element) { return (element.scrollwidth > element.offsetwidth); } function alertoverflow(element) { if (isoverflowing(element)) { alert('contents are overflowing the container.'); } else { alert('no overflows!'); } } buttonone.addeventlistener('click', function() { alertoverflow(divone); }); buttontwo.addeventlistener('click', function() { alertoverflow(divtwo); }); </script> </html> result specification specification status comment css object model (cssom) view modulethe definition of 'element.scrollwidth' in that specification.
Element: scroll event - Web APIs
// reference: http://www.html5rocks.com/en/tutorials/speed/animations/ let last_known_scroll_position = 0; let ticking = false; function dosomething(scroll_pos) { // do something with the scroll position } window.addeventlistener('scroll', function(e) { last_known_scroll_position = window.scrolly; if (!ticking) { window.requestanimationframe(function() { dosomething(last_known_scroll_position); ticking = false; }); ticking = true; } }); note: you can find more examples on the resize event page.
Element: select event - Web APIs
examples selection logger <input value="try selecting some text in this element."> <p id="log"></p> function logselection(event) { const log = document.getelementbyid('log'); const selection = event.target.value.substring(event.target.selectionstart, event.target.selectionend); log.textcontent = `you selected: ${selection}`; } const input = document.queryselector('input'); input.addeventlistener('select', logselection); onselect equivalent you can also set up the event handler using the onselect property: input.onselect = logselection; specifications specification status ui eventsthe definition of 'select' in that specification.
Element.setCapture() - Web APIs
<html> <head> <title>mouse capture example</title> <style type="text/css"> #mybutton { border: solid black 1px; color: black; padding: 2px; box-shadow: black 2px 2px; } </style> <script type="text/javascript"> function init() { var btn = document.getelementbyid("mybutton"); if (btn.setcapture) { btn.addeventlistener("mousedown", mousedown, false); btn.addeventlistener("mouseup", mouseup, false); } else { document.getelementbyid("output").innerhtml = "sorry, there appears to be no setcapture support on this browser"; } } function mousedown(e) { e.target.setcapture(); e.target.addeventlistener("mousemove", mousemoved, false); } function mouseu...
Element: show event - Web APIs
bubbles no cancelable no interface event event handler property onshow examples <div contextmenu="test"></div> <menu type="context" id="test"> <menuitem label="alert" onclick="alert('the alert label has been clicked')" /> </menu> <script> document.getelementbyid("test").addeventlistener("show", function(e){ alert("the context menu will be displayed"); }, false); </script> specifications specification status html5the definition of 'show event' in that specification.
Element.toggleAttribute() - Web APIs
html <input value="text"> <button>toggleattribute("readonly")</button> javascript var button = document.queryselector("button"); var input = document.queryselector("input"); button.addeventlistener("click", function(){ input.toggleattribute("readonly"); }); result dom methods dealing with element's attributes: not namespace-aware, most commonly used methods namespace-aware variants (dom level 2) dom level 1 methods for dealing with attr nodes directly (seldom used) dom level 2 namespace-aware methods for dealing with attr nodes directly (seldom used) setattribute (dom 1) setat...
Element: underflow event - Web APIs
tyle> #wrapper { width: 20px; height: 20px; background: #000; padding: 5px; overflow: hidden; } #child { width: 40px; height: 40px; border: 2px solid grey; background: #ccc; } </style> <script> var wrapper = document.getelementbyid("wrapper"), child = document.getelementbyid("child"), toggle = document.getelementbyid("toggle"); wrapper.addeventlistener("overflow", function( event ) { console.log( event ); }, false); wrapper.addeventlistener("underflow", function( event ) { console.log( event ); }, false); toggle.addeventlistener("change", function( event ) { if ( event.target.checked ) { child.style.width = "40px"; child.style.height = "40px"; } else { child.style.width = "10px"; ...
Element: wheel event - Web APIs
content: center; } div { width: 105px; height: 105px; background: #cdf; padding: 5px; } function zoom(event) { event.preventdefault(); scale += event.deltay * -0.01; // restrict scale scale = math.min(math.max(.125, scale), 4); // apply scale transform el.style.transform = `scale(${scale})`; } let scale = 1; const el = document.queryselector('div'); el.onwheel = zoom; addeventlistener equivalent the event handler can also be set up using the addeventlistener() method: el.addeventlistener('wheel', zoom); specifications specification status comment ui eventsthe definition of 'wheel' in that specification.
Comparison of Event Targets - Web APIs
l = e.relatedtarget; document.getelementbyid('explicitoriginaltarget').innerhtml = e.explicitoriginaltarget; document.getelementbyid('originaltarget').innerhtml = e.originaltarget; } function handlemouseover(e) { document.getelementbyid('target').innerhtml = e.target; document.getelementbyid('relatedtarget').innerhtml = e.relatedtarget; } document.addeventlistener('click', handleclicks, false); document.addeventlistener('mouseover', handlemouseover, false); </script> </body> </html> use of target and relatedtarget the relatedtarget property for the mouseover event holds the node that the mouse was previously over.
Event.cancelable - Web APIs
WebAPIEventcancelable
console.warn(`the following event couldn't be canceled:`); console.dir(event); } } document.addeventlistener('wheel', preventscrollwheel); notes whether an event can be canceled or not is something that's determined when that event is initialized.
Event.composed - Web APIs
WebAPIEventcomposed
t = this.getattribute('text'); let shadowroot = this.attachshadow({mode: 'open'}) .appendchild(pelem); } }); we then insert one of each element into our page: <open-shadow text="i have an open shadow root"></open-shadow> <closed-shadow text="i have a closed shadow root"></closed-shadow> then include a click event listener on the <html> element: document.queryselector('html').addeventlistener('click',function(e) { console.log(e.composed); console.log(e.composedpath()); }); when you click on the <open-shadow> element and then the <closed-shadow> element, you'll notice two things.
Event.composedPath() - Web APIs
t = this.getattribute('text'); let shadowroot = this.attachshadow({mode: 'open'}) .appendchild(pelem); } }); we then insert one of each element into our page: <open-shadow text="i have an open shadow root"></open-shadow> <closed-shadow text="i have a closed shadow root"></closed-shadow> then include a click event listener on the <html> element: document.queryselector('html').addeventlistener('click',function(e) { console.log(e.composed); console.log(e.composedpath()); }); when you click on the <open-shadow> element and then the <closed-shadow> element, you'll notice two things.
Event.currentTarget - Web APIs
function hide(e){ e.currenttarget.style.visibility = 'hidden'; console.log(e.currenttarget); // when this function is used as an event handler: this === e.currenttarget } var ps = document.getelementsbytagname('p'); for(var i = 0; i < ps.length; i++){ // console: print the clicked <p> element ps[i].addeventlistener('click', hide, false); } // console: print <body> document.body.addeventlistener('click', hide, false); // click around and make paragraphs disappear note: the value of event.currenttarget is only available while the event is being handled.
Event.defaultPrevented - Web APIs
ent) { event.preventdefault(); } function logclick(event) { const log = document.getelementbyid('log'); if (event.target.tagname === 'a') { if (event.defaultprevented) { log.innertext = 'sorry, but you cannot visit this link!\n' + log.innertext; } else { log.innertext = 'visiting link...\n' + log.innertext; } } } const a = document.getelementbyid('link2'); a.addeventlistener('click', stoplink); document.addeventlistener('click', logclick); result specifications specification status comment domthe definition of 'event.defaultprevented()' in that specification.
Event.initEvent() - Web APIs
WebAPIEventinitEvent
elem.addeventlistener('click', function (e) { // e.target matches elem }, false); elem.dispatchevent(event); specifications specification status comment domthe definition of 'event.initevent()' in that specification.
Event.msConvertURL() - Web APIs
example var bloblist = []; document.getelementbyid("pastezone").addeventlistener('paste', handlepaste, false); function handlepaste(evt) { var filelist = window.clipboarddata.files; // note that window.datatransfer.files is not applicable.
Event.target - Web APIs
WebAPIEventtarget
.createelement('li'); const li2 = document.createelement('li'); ul.appendchild(li1); ul.appendchild(li2); function hide(evt) { // e.target refers to the clicked <li> element // this is different than e.currenttarget, which would refer to the parent <ul> in this context evt.target.style.visibility = 'hidden'; } // attach the listener to the list // it will fire when each <li> is clicked ul.addeventlistener('click', hide, false); specifications specification status comment domthe definition of 'event.target' in that specification.
Event.timeStamp - Web APIs
WebAPIEventtimeStamp
</p> <p>timestamp: <span id="time">-</span></p> javascript function gettime(event) { var time = document.getelementbyid("time"); time.firstchild.nodevalue = event.timestamp; } document.body.addeventlistener("keypress", gettime); result reduced time precision to offer protection against timing attacks and fingerprinting, the precision of event.timestamp might get rounded depending on browser settings.
Event.type - Web APIs
WebAPIEventtype
html <p>press any key or click the mouse to get the event type.</p> <p id="log"></p> javascript function geteventtype(event) { const log = document.getelementbyid('log'); log.innertext = event.type + '\n' + log.innertext; } // keyboard events document.addeventlistener('keydown', geteventtype, false); // first document.addeventlistener('keypress', geteventtype, false); // second document.addeventlistener('keyup', geteventtype, false); // third // mouse events document.addeventlistener('mousedown', geteventtype, false); // first document.addeventlistener('mouseup', geteventtype, false); // second document.addeventlistener('click', geteventtype, false); ...
Event - Web APIs
WebAPIEvent
event-handlers are usually connected (or "attached") to various html elements (such as <button>, <div>, <span>, etc.) using eventtarget.addeventlistener(), and this generally replaces using the old html event handler attributes.
EventSource: error event - Web APIs
bubbles no cancelable no interface event or errorevent event handler property eventsource.onerror examples var evtsource = new eventsource('sse.php'); // addeventlistener version evtsource.addeventlistener('error', (e) => { console.log("an error occurred while attempting to connect."); }); // onerror version evtsource.onerror = (e) => { console.log("an error occurred while attempting to connect."); }; specifications specification status html living standardthe definition of 'error event' in that specification.
EventSource: message event - Web APIs
var evtsource = new eventsource('sse.php'); var eventlist = document.queryselector('ul'); evtsource.addeventlistener('message', (e) => { var newelement = document.createelement("li"); newelement.textcontent = "message: " + e.data; eventlist.appendchild(newelement); }); onmessage equivalent evtsource.onmessage = (e) => { var newelement = document.createelement("li"); newelement.textcontent = "message: " + e.data; eventlist.appendchild(newelement); }; specifications specification sta...
EventSource: open event - Web APIs
bubbles no cancelable no interface event event handler property eventsource.onopen examples var evtsource = new eventsource('sse.php'); // addeventlistener version evtsource.addeventlistener('open', (e) => { console.log("the connection has been established."); }); // onopen version evtsource.onopen = (e) => { console.log("the connection has been established."); }; specifications specification status html living standardthe definition of 'open event' in that specification.
EventTarget() - Web APIs
examples class myeventtarget extends eventtarget { constructor(mysecret) { super(); this._secret = mysecret; } get secret() { return this._secret; } }; let myeventtarget = new myeventtarget(5); let value = myeventtarget.secret; // == 5 myeventtarget.addeventlistener("foo", function(e) { this._secret = e.detail; }); let event = new customevent("foo", { detail: 7 }); myeventtarget.dispatchevent(event); let newvalue = myeventtarget.secret; // == 7 specifications specification status comment domthe definition of 'eventtarget() constructor' in that specification.
ExtendableEvent.waitUntil() - Web APIs
example using waituntil() within a service worker's install event: addeventlistener('install', event => { const precache = async () => { const cache = await caches.open('static-v1'); return cache.addall([ '/', '/about/', '/static/styles.css' ]); }; event.waituntil(precache()); }); specifications specification status comment service workersthe definition of 'waituntil()' in that specification.
ExtendableEvent - Web APIs
var cache_version = 1; var current_caches = { prefetch: 'prefetch-cache-v' + cache_version }; self.addeventlistener('install', function(event) { var urlstoprefetch = [ './static/pre_fetched.txt', './static/pre_fetched.html', 'https://www.chromium.org/_/rsrc/1302286216006/config/customlogo.gif' ]; console.log('handling install event.
ExtendableMessageEvent.data - Web APIs
var port; self.addeventlistener('push', function(e) { var obj = e.data.json(); if(obj.action === 'subscribe' || obj.action === 'unsubscribe') { port.postmessage(obj); } else if(obj.action === 'init' || obj.action === 'chatmsg') { port.postmessage(obj); } }); self.onmessage = function(e) { console.log(e.data); port = e.ports[0]; } specifications specification status comment servic...
ExtendableMessageEvent.lastEventId - Web APIs
var port; self.addeventlistener('push', function(e) { var obj = e.data.json(); if(obj.action === 'subscribe' || obj.action === 'unsubscribe') { port.postmessage(obj); } else if(obj.action === 'init' || obj.action === 'chatmsg') { port.postmessage(obj); } }); self.onmessage = function(e) { console.log(e.lasteventid); port = e.ports[0]; } specifications specification status comment ...
ExtendableMessageEvent.origin - Web APIs
var port; self.addeventlistener('push', function(e) { var obj = e.data.json(); if(obj.action === 'subscribe' || obj.action === 'unsubscribe') { port.postmessage(obj); } else if(obj.action === 'init' || obj.action === 'chatmsg') { port.postmessage(obj); } }); self.onmessage = function(e) { console.log(e.origin); port = e.ports[0]; } specifications specification status comment serv...
ExtendableMessageEvent.ports - Web APIs
var port; self.addeventlistener('push', function(e) { var obj = e.data.json(); if(obj.action === 'subscribe' || obj.action === 'unsubscribe') { port.postmessage(obj); } else if(obj.action === 'init' || obj.action === 'chatmsg') { port.postmessage(obj); } }); self.onmessage = function(e) { port = e.ports[0]; } specifications specification status comment service workersthe definition...
ExtendableMessageEvent.source - Web APIs
var port; self.addeventlistener('push', function(e) { var obj = e.data.json(); if(obj.action === 'subscribe' || obj.action === 'unsubscribe') { port.postmessage(obj); } else if(obj.action === 'init' || obj.action === 'chatmsg') { port.postmessage(obj); } }); self.onmessage = function(e) { console.log(e.source); port = e.ports[0]; } specifications specification status comment serv...
ExtendableMessageEvent - Web APIs
// in the page being controlled if (navigator.serviceworker) { navigator.serviceworker.register('service-worker.js'); navigator.serviceworker.addeventlistener('message', event => { // event is a messageevent object console.log(`the service worker sent me a message: ${event.data}`); }); navigator.serviceworker.ready.then( registration => { registration.active.postmessage("hi service worker"); }); } the service worker can receive the message by listening to the message event: // in the service worker addeventlistener('message', even...
FetchEvent.preloadResponse - Web APIs
addeventlistener('fetch', event => { event.respondwith(async function() { // respond from the cache if we can const cachedresponse = await caches.match(event.request); if (cachedresponse) return cachedresponse; // else, use the preloaded response, if it's there const response = await event.preloadresponse; if (response) return response; // else try the network.
FetchEvent.client - Web APIs
WebAPIFetchEventclient
example self.addeventlistener('fetch', function(event) { console.log(event.client); ​}); ...
FetchEvent.clientId - Web APIs
example self.addeventlistener('fetch', function(event) { console.log(event.clientid); ​}); specifications specification status comment service workersthe definition of 'clientid' in that specification.
FetchEvent.isReload - Web APIs
example self.addeventlistener('fetch', function(event) { event.respondwith( if (event.isreload) { //return something } else { //return something else }; ); ​}); ...
FetchEvent.navigationPreload - Web APIs
addeventlistener('fetch', event => { event.respondwith(async function() { // respond from the cache if we can const cachedresponse = await caches.match(event.request); if (cachedresponse) return cachedresponse; // else, use the preloaded response, if it's there const response = await event.preloadresponse; if (response) return response; // else try the network.
FetchEvent.replacesClientId - Web APIs
example self.addeventlistener('fetch', function(event) { console.log(event.replacesclientid); }); specifications specification status comment service workersthe definition of 'replacesclientid' in that specification.
FetchEvent.request - Web APIs
self.addeventlistener('fetch', function(event) { console.log('handling fetch event for', event.request.url); event.respondwith( caches.match(event.request).then(function(response) { if (response) { console.log('found response in cache:', response); return response; } console.log('no response found in cache.
FetchEvent.respondWith() - Web APIs
addeventlistener('fetch', event => { // prevent the default, and handle the request ourselves.
FetchEvent.resultingClientId - Web APIs
example self.addeventlistener('fetch', function(event) { console.log(event.resultingclientid); }); specifications specification status comment service workersthe definition of 'resultingclientid' in that specification.
FetchEvent - Web APIs
self.addeventlistener('fetch', event => { // let the browser do its default thing // for non-get requests.
Using Fetch - Web APIs
they can also be created programmatically via javascript, but this is only really useful in serviceworkers, when you are providing a custom response to a received request using a respondwith() method: const mybody = new blob(); addeventlistener('fetch', function(event) { // serviceworker intercepting a fetch event.respondwith( new response(mybody, { headers: { 'content-type': 'text/plain' } }) ); }); the response() constructor takes two optional arguments — a body for the response, and an init object (similar to the one that request() accepts.) note: the static method error() simply returns an error response...
File.lastModified - Web APIs
WebAPIFilelastModified
example reading from file input <input type="file" multiple id="fileinput"> const fileinput = document.queryselector('#fileinput'); fileinput.addeventlistener('change', (event) => { // files is a filelist object (similar to nodelist) const files = event.target.files; for (let file of files) { const date = new date(file.lastmodified); console.log(`${file.name} has a last modified date of ${date}`); } }); try the results out below: dynamically created files if a file is created dynamically, the last modified time can be supplied in...
File.webkitRelativePath - Web APIs
html content <input type="file" id="filepicker" name="filelist" webkitdirectory multiple /> <ul id="listing"></ul> javascript content document.getelementbyid("filepicker").addeventlistener("change", function(event) { let output = document.getelementbyid("listing"); let files = event.target.files; for (let i=0; i<files.length; i++) { let item = document.createelement("li"); item.innerhtml = files[i].webkitrelativepath; output.appendchild(item); }; }, false); result specifications specification status comment file and directory e...
FileReader: error event - Web APIs
bubbles no cancelable no interface progressevent event handler property filereader.onerror examples const fileinput = document.queryselector('input[type="file"]'); const reader = new filereader(); function handleselected(e) { const selectedfile = fileinput.files[0]; if (selectedfile) { reader.addeventlistener('error', () => { console.error(`error occurred reading file: ${selectedfile.name}`); }); reader.addeventlistener('load', () => { console.error(`file: ${selectedfile.name} read successfully`); }); reader.readasdataurl(selectedfile); } } fileinput.addeventlistener('change', handleselected); specifications specification st...
FileSystemDirectoryEntry.getDirectory() - Web APIs
let dictionary = null; function loaddictionaryforlanguage(appdatadirentry, lang) { dictionary = null; appdatadirentry.getdirectory("dictionaries", {}, function(direntry) { direntry.getfile(lang + "-dict.json", {}, function(fileentry) { fileentry.file(function(dictfile)) { let reader = new filereader(); reader.addeventlistener("loadend", function() { dictionary = json.parse(reader.result); }); reader.readastext(dictfile); }); }); }); } the loaddictionaryforlanguage() function starts by using getdirectory() to obtain the filesystemdirectoryentry object representing a subfolder named "dictionaries" located inside the specified app data directory.
FileSystemDirectoryEntry.getFile() - Web APIs
let dictionary = null; function loaddictionaryforlanguage(appdatadirentry, lang) { dictionary = null; appdatadirentry.getdirectory("dictionaries", {}, function(direntry) { direntry.getfile(lang + "-dict.json", {}, function(fileentry) { fileentry.file(function(dictfile)) { let reader = new filereader(); reader.addeventlistener("loadend", function() { dictionary = json.parse(reader.result); }); reader.readastext(dictfile); }); }); }); } the loaddictionaryforlanguage() function starts by using getdirectory() to obtain the filesystemdirectoryentry object representing a subfolder named "dictionaries" located inside the specified app data directory.
FileSystemDirectoryReader.readEntries() - Web APIs
first, we prevent the dragover event from being handled by the default handler, so that our drop zone can receive the drop: dropzone.addeventlistener("dragover", function(event) { event.preventdefault(); }, false); the event handler that kicks everything off, of course, is the handler for the drop event: dropzone.addeventlistener("drop", function(event) { let items = event.datatransfer.items; event.preventdefault(); listing.innerhtml = ""; for (let i=0; i<items.length; i++) { let item = items[i].webkitgetasentry(); if...
FormDataEvent.formData - Web APIs
examples // grab reference to form const formelem = document.queryselector('form'); // submit handler formelem.addeventlistener('submit', (e) => { // on form submission, prevent default e.preventdefault(); // construct a formdata object, which fires the formdata event new formdata(formelem); }); // formdata handler to retrieve data formelem.addeventlistener('formdata', (e) => { console.log('formdata fired'); // get the form data from the event object let data = e.formdata; for (var value of data.values()) { console.log(value); } // submit th...
FormDataEvent - Web APIs
examples // grab reference to form const formelem = document.queryselector('form'); // submit handler formelem.addeventlistener('submit', (e) => { // on form submission, prevent default e.preventdefault(); // construct a formdata object, which fires the formdata event new formdata(formelem); }); // formdata handler to retrieve data formelem.addeventlistener('formdata', (e) => { console.log('formdata fired'); // get the form data from the event object let data = e.formdata; for (var value of data.values...
Guide to the Fullscreen API - Web APIs
document.addeventlistener("keydown", function(e) { if (e.keycode == 13) { togglefullscreen(); } }, false); toggling fullscreen mode this code is called when the user hits the enter key, as seen above.
Fullscreen API - Web APIs
document.addeventlistener("keypress", function(e) { if (e.keycode === 13) { togglefullscreen(); } }, false); toggling full-screen mode this code is called by the event handler above when the user hits the enter key.
Gamepad.id - Web APIs
WebAPIGamepadid
syntax readonly attribute domstring id; example window.addeventlistener("gamepadconnected", function() { var gp = navigator.getgamepads()[0]; gamepadinfo.innerhtml = "gamepad connected at index " + gp.index + ": " + gp.id + "."; }); value a string.
Gamepad.index - Web APIs
WebAPIGamepadindex
syntax readonly attribute long index; example window.addeventlistener("gamepadconnected", function() { var gp = navigator.getgamepads()[0]; gamepadinfo.innerhtml = "gamepad connected at index " + gp.index + ": " + gp.id + "."; }); value a number.
Gamepad - Web APIs
WebAPIGamepad
example window.addeventlistener("gamepadconnected", function(e) { console.log("gamepad connected at index %d: %s.
GamepadEvent.gamepad - Web APIs
window.addeventlistener("gamepadconnected", function(e) { console.log("gamepad connected at index %d: %s.
Using the Geolocation API - Web APIs
e: ${latitude} °, longitude: ${longitude} °`; } function error() { status.textcontent = 'unable to retrieve your location'; } if(!navigator.geolocation) { status.textcontent = 'geolocation is not supported by your browser'; } else { status.textcontent = 'locating…'; navigator.geolocation.getcurrentposition(success, error); } } document.queryselector('#find-me').addeventlistener('click', geofindme); result ...
Geolocation API - Web APIs
e: ${latitude} °, longitude: ${longitude} °`; } function error() { status.textcontent = 'unable to retrieve your location'; } if(!navigator.geolocation) { status.textcontent = 'geolocation is not supported by your browser'; } else { status.textcontent = 'locating…'; navigator.geolocation.getcurrentposition(success, error); } } document.queryselector('#find-me').addeventlistener('click', geofindme); result specifications specification status comment geolocation api recommendation ...
GlobalEventHandlers.onanimationcancel - Web APIs
function handlecancelevent(event) { log("animation canceled", event); }; then we add a method to handle toggle display between "flex" and "none" and establish it as the handler for a click event on the "hide/show" the box button: document.getelementbyid('togglebox').addeventlistener('click', function() { if (box.style.display == "none") { box.style.display = "flex"; document.getelementbyid("togglebox").innerhtml = "hide the box"; } else { box.style.display = "none"; document.getelementbyid("togglebox").innerhtml = "show the box"; } }); toggling the box to display: none has the effect of aborting its animation.
GlobalEventHandlers.onanimationend - Web APIs
then we set up the event handlers for the animationstart and animationend events: let box = document.getelementbyid("box"); box.onanimationstart = function(event) { log("animation started", event); } box.onanimationend = function(event) { log("animation stopped", event); }; finally, we set up a handler for a click on the button that runs the animation: document.getelementbyid("play").addeventlistener("click", function(event) { document.getelementbyid("box").classname = "slideanimation"; event.target.style.display = "none"; }, false); this sets the class of the box we want to animate to the class that contains the animation description, then hides the play button because this example will only run the animation once.
GlobalEventHandlers.onanimationiteration - Web APIs
finally, we set up a handler for a click on the button that runs the animation: document.getelementbyid("play").addeventlistener("click", function(event) { box.style.animationplaystate = "running"; iterationcounter++; }, false); this sets the box element's animation-play-state to "running" and increments the iteration counter.
GlobalEventHandlers.onanimationstart - Web APIs
then we set up the event handlers for the animationstart and animationend events: let box = document.getelementbyid("box"); box.onanimationstart = function(event) { log("animation started", event); } box.onanimationend = function(event) { log("animation stopped", event); }; finally, we set up a handler for a click on the button that runs the animation: document.getelementbyid("play").addeventlistener("click", function(event) { document.getelementbyid("box").classname = "slideanimation"; event.target.style.display = "none"; }, false); this sets the class of the box we want to animate to the class that contains the animation description, then hides the play button because this example will only run the animation once.
GlobalEventHandlers.onauxclick - Web APIs
you may prefer to use the eventtarget.addeventlistener() method instead, since it's more flexible.
GlobalEventHandlers.oncancel - Web APIs
you may prefer to use the eventtarget.addeventlistener() method instead, since it's more flexible.
GlobalEventHandlers.onclick - Web APIs
you may prefer to use the eventtarget.addeventlistener() method instead, since it's more flexible.
GlobalEventHandlers.onclose - Web APIs
you may prefer to use the eventtarget.addeventlistener() method instead, since it's more flexible.
GlobalEventHandlers.oncontextmenu - Web APIs
you may prefer to use the eventtarget.addeventlistener() method instead, since it's more flexible.
GlobalEventHandlers.ondblclick - Web APIs
you may prefer to use the eventtarget.addeventlistener() method instead, since it's more flexible.
GlobalEventHandlers.onformdata - Web APIs
examples // grab reference to form const formelem = document.queryselector('form'); // submit handler formelem.addeventlistener('submit', (e) => { // on form submission, prevent default e.preventdefault(); // construct a formdata object, which fires the formdata event new formdata(formelem); }); // formdata handler to retrieve data formelem.onformdata = (e) => { console.log('formdata fired'); // get the form data from the event object let data = e.formdata; for (var value of data.values()) { consol...
GlobalEventHandlers.onload - Web APIs
there are also dom events like domcontentloaded and domframecontentloaded (which can be handled using eventtarget.addeventlistener()) which are fired after the dom for the page has been constructed, but do not wait for other resources to finish loading.
GlobalEventHandlers.onloadend - Web APIs
examples html content <img src="myimage.jpg"> javascript content // 'loadstart' fires first, then 'load', then 'loadend' image.addeventlistener('load', function(e) { console.log('image loaded'); }); image.addeventlistener('loadstart', function(e) { console.log('image load started'); }); image.addeventlistener('loadend', function(e) { console.log('image load finished'); }); ...
GlobalEventHandlers.onloadstart - Web APIs
examples html content <img src="myimage.jpg"> javascript content // 'loadstart' fires first, then 'load', then 'loadend' image.addeventlistener('load', function(e) { console.log('image loaded'); }); image.addeventlistener('loadstart', function(e) { console.log('image load started'); }); image.addeventlistener('loadend', function(e) { console.log('image load finished'); }); specifications specification status comment html living standardthe definition of 'onloadstart' in that specification.
GlobalEventHandlers.onscroll - Web APIs
for greater flexibility, you can pass a scroll event to the eventtarget.addeventlistener() method instead.
Gyroscope.x - Web APIs
WebAPIGyroscopex
let gyroscope = new gyroscope({frequency: 60}); gyroscope.addeventlistener('reading', e => { console.log("angular velocity along the x-axis " + gyroscope.x); console.log("angular velocity along the y-axis " + gyroscope.y); console.log("angular velocity along the z-axis " + gyroscope.z); }); gyroscope.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Gyroscope.y - Web APIs
WebAPIGyroscopey
let gyroscope = new gyroscope({frequency: 60}); gyroscope.addeventlistener('reading', e => { console.log("angular velocety along the x-axis " + gyroscope.x); console.log("angular velocety along the y-axis " + gyroscope.y); console.log("angular velocety along the z-axis " + gyroscope.z); }); gyroscope.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Gyroscope.z - Web APIs
WebAPIGyroscopez
let gyroscope = new gyroscope({frequency: 60}); gyroscope.addeventlistener('reading', e => { console.log("angular velocety along the x-axis " + gyroscope.x); console.log("angular velocety along the y-axis " + gyroscope.y); console.log("angular velocety along the z-axis " + gyroscope.z); }); gyroscope.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Gyroscope - Web APIs
WebAPIGyroscope
let gyroscope = new gyroscope({frequency: 60}); gyroscope.addeventlistener('reading', e => { console.log("angular velocity along the x-axis " + gyroscope.x); console.log("angular velocity along the y-axis " + gyroscope.y); console.log("angular velocity along the z-axis " + gyroscope.z); }); gyroscope.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Audio() - Web APIs
the event-based approach is best: myaudioelement.addeventlistener("canplaythrough", event => { /* the audio is now playable; play it if permissions allow */ myaudioelement.play(); }); memory usage and management if all references to an audio element created using the audio() constructor are deleted, the element itself won't be removed from memory by the javascript runtime's garbage collection mechanism if playback is currently underway.
HTMLButtonElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <button id="test">button</button> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const button = document.getelementbyid("test"); for(var i = 0; i < button.labels.length; i++) { console.log(button.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLCanvasElement.mozGetAsFile() - Web APIs
function draw() { var canvas = document.getelementbyid('canvas'); var ctx = canvas.getcontext('2d'); ctx.fillstyle = 'rgb(200, 0, 0)'; ctx.fillrect(10, 10, 55, 50); ctx.fillstyle = 'rgba(0, 0, 200, 0.5)'; ctx.fillrect(30, 30, 55, 50); var link = document.getelementbyid('link'); link.addeventlistener('click', copy); } function copy() { var canvas = document.getelementbyid('canvas'); var f = canvas.mozgetasfile('test.png'); var reader = new filereader(); reader.readasdataurl(f); reader.onloadend = function() { var newimg = document.createelement('img'); newimg.src = reader.result; document.body.appendchild(newimg); } } window.addeventlistener('load', draw); specificat...
HTMLCanvasElement.toDataURL() - Web APIs
color in this example): html <img class="grayscale" src="mypicture.png" alt="description of my picture" /> javascript window.addeventlistener('load', removecolors); function showcolorimg() { this.style.display = 'none'; this.nextsibling.style.display = 'inline'; } function showgrayimg() { this.previoussibling.style.display = 'inline'; this.style.display = 'none'; } function removecolors() { var aimages = document.getelementsbyclassname('grayscale'), nimgslen = aimages.length, ocanvas = document.createelement('c...
HTMLCanvasElement: webglcontextcreationerror event - Web APIs
bubbles yes cancelable yes interface webglcontextevent event handler property none example var canvas = document.getelementbyid('canvas'); canvas.addeventlistener('webglcontextcreationerror', function(e) { console.log(e.statusmessage || 'unknown error'); }, false); var gl = canvas.getcontext('webgl'); // logs statusmessage or "unknown error" if unable to create webgl context specifications specification status comment webgl 1.0the definition of 'webglcontextcreationerror' in that specification.
HTMLCanvasElement: webglcontextlost event - Web APIs
bubbles yes cancelable yes interface webglcontextevent event handler property none example with the help of the webgl_lose_context extension, you can simulate the webglcontextlost event: const canvas = document.getelementbyid('canvas'); const gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextlost', (event) => { console.log(event); }); gl.getextension('webgl_lose_context').losecontext(); // "webglcontextlost" event is logged.
HTMLCanvasElement: webglcontextrestored event - Web APIs
bubbles yes cancelable yes interface webglcontextevent event handler property none example with the help of the webgl_lose_context extension, you can simulate the webglcontextrestored event: var canvas = document.getelementbyid('canvas'); var gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextrestored', function(e) { console.log(e); }, false); gl.getextension('webgl_lose_context').restorecontext(); // "webglcontextrestored" event is logged.
HTMLCanvasElement - Web APIs
events listen to these events using addeventlistener().
HTMLDetailsElement: toggle event - Web APIs
details> </section> css body { display: flex; flex-direction: row-reverse; } #log { flex-shrink: 0; padding-left: 3em; } #summaries { flex-grow: 1; } javascript function logitem(e) { const item = document.queryselector(`[data-id=${e.target.id}]`); item.toggleattribute('hidden'); } const chapters = document.queryselectorall('details'); chapters.foreach((chapter) => { chapter.addeventlistener('toggle', logitem); }); result specifications specification status comment html living standardthe definition of 'toggle event' in that specification.
HTMLDetailsElement - Web APIs
events listen to this event using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
HTMLDialogElement.close() - Web APIs
'); var cancelbutton = document.getelementbyid('cancel'); var dialog = document.getelementbyid('favdialog'); dialog.returnvalue = 'favanimal'; function opencheck(dialog) { if(dialog.open) { console.log('dialog open'); } else { console.log('dialog closed'); } } // update button opens a modal dialog updatebutton.addeventlistener('click', function() { dialog.showmodal(); opencheck(dialog); }); // form cancel button closes the dialog box cancelbutton.addeventlistener('click', function() { dialog.close('animalnotchosen'); opencheck(dialog); }); })(); </script> note: you can find this example on github as htmldialogelement-basic (see it live also).
HTMLDialogElement.open - Web APIs
'); var cancelbutton = document.getelementbyid('cancel'); var dialog = document.getelementbyid('favdialog'); dialog.returnvalue = 'favanimal'; function opencheck(dialog) { if(dialog.open) { console.log('dialog open'); } else { console.log('dialog closed'); } } // update button opens a modal dialog updatebutton.addeventlistener('click', function() { dialog.showmodal(); opencheck(dialog); }); // form cancel button closes the dialog box cancelbutton.addeventlistener('click', function() { dialog.close('animalnotchosen'); opencheck(dialog); }); })(); </script> note: you can find this example on github as htmldialogelement-basic (see it live also).
HTMLDialogElement.returnValue - Web APIs
osed'); } } function handleuserinput(returnvalue) { if (returnvalue === 'cancel' || returnvalue == null) { // user canceled the dialog, do nothing } else if (returnvalue === 'confirm') { // user chose a favorite animal, do something with it } } // “update details” button opens the <dialog> modally updatebutton.addeventlistener('click', function() { dialog.showmodal(); opencheck(dialog); handleuserinput(dialog.returnvalue); }); })(); </script> note: you can find this example on github as htmldialogelement-basic (see it live also).
HTMLDialogElement.show() - Web APIs
'); var cancelbutton = document.getelementbyid('cancel'); var dialog = document.getelementbyid('favdialog'); dialog.returnvalue = 'favanimal'; function opencheck(dialog) { if(dialog.open) { console.log('dialog open'); } else { console.log('dialog closed'); } } // update button opens a modal dialog updatebutton.addeventlistener('click', function() { dialog.showmodal(); opencheck(dialog); }); // form cancel button closes the dialog box cancelbutton.addeventlistener('click', function() { dialog.close('animalnotchosen'); opencheck(dialog); }); })(); </script> specifications specification status comment html living standardthe defi...
HTMLDialogElement.showModal() - Web APIs
'); var cancelbutton = document.getelementbyid('cancel'); var dialog = document.getelementbyid('favdialog'); dialog.returnvalue = 'favanimal'; function opencheck(dialog) { if(dialog.open) { console.log('dialog open'); } else { console.log('dialog closed'); } } // update button opens a modal dialog updatebutton.addeventlistener('click', function() { dialog.showmodal(); opencheck(dialog); }); // form cancel button closes the dialog box cancelbutton.addeventlistener('click', function() { dialog.close('animalnotchosen'); opencheck(dialog); }); })(); </script> note: you can find this example on github as htmldialogelement-basic (see it live also).
HTMLDialogElement - Web APIs
'); var cancelbutton = document.getelementbyid('cancel'); var dialog = document.getelementbyid('favdialog'); dialog.returnvalue = 'favanimal'; function opencheck(dialog) { if(dialog.open) { console.log('dialog open'); } else { console.log('dialog closed'); } } // update button opens a modal dialog updatebutton.addeventlistener('click', function() { dialog.showmodal(); opencheck(dialog); }); // form cancel button closes the dialog box cancelbutton.addeventlistener('click', function() { dialog.close('animalnotchosen'); opencheck(dialog); }); })(); </script> note: you can find this example on github as htmldialogelement-basic (see it live also).
HTMLElement: beforeinput event - Web APIs
html <input placeholder="enter some text" name="name"/> <p id="values"></p> javascript const input = document.queryselector('input'); const log = document.getelementbyid('values'); input.addeventlistener('beforeinput', updatevalue); function updatevalue(e) { log.textcontent = e.target.value; } result specifications specification status ui eventsthe definition of 'beforeinput event' in that specification.
HTMLElement: gotpointercapture event - Web APIs
const para = document.queryselector('p'); para.addeventlistener('gotpointercapture', () => { console.log('i\'ve been captured!') }); para.addeventlistener('pointerdown', (event) => { para.setpointercapture(event.pointerid); }); the same example, using the ongotpointercapture event handler property: const para = document.queryselector('p'); para.ongotpointercapture = () => { console.log('i\'ve been captured!') }; para.addeventlistener('pointerdown'...
HTMLElement.hidden - Web APIs
javascript document.getelementbyid("okbutton") .addeventlistener("click", function() { document.getelementbyid("welcome").hidden = true; document.getelementbyid("awesome").hidden = false; }, false); this code sets up a handler for the welcome panel's "ok" button that hides the welcome panel and makes the follow-up panel—with the curious name "awesome"—visible in its place.
HTMLElement: input event - Web APIs
html <input placeholder="enter some text" name="name"/> <p id="values"></p> javascript const input = document.queryselector('input'); const log = document.getelementbyid('values'); input.addeventlistener('input', updatevalue); function updatevalue(e) { log.textcontent = e.target.value; } result specifications specification status html living standardthe definition of 'input event' in that specification.
HTMLElement: lostpointercapture event - Web APIs
const para = document.queryselector('p'); para.addeventlistener('lostpointercapture', () => { console.log('i\'ve been released!') }); para.addeventlistener('pointerdown', (event) => { para.setpointercapture(event.pointerid); }); the same example, but using the onlostpointercapture event handler property: const para = document.queryselector('p'); para.onlostpointercapture = () => { console.log('i\'ve been released!') }; para.addeventlistener('point...
HTMLElement: pointercancel event - Web APIs
examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointercancel', (event) => { console.log('pointer event cancelled'); }); using the onpointercancel event handler property: const para = document.queryselector('p'); para.onpointercancel = (event) => { console.log('pointer event cancelled'); }; specifications specification status pointer events o...
HTMLElement: pointerdown event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerdown examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointerdown', (event) => { console.log('pointer down event'); }); using the onpointerdown event handler property: const para = document.queryselector('p'); para.onpointerdown = (event) => { console.log('pointer down event'); }; specifications specification status pointer events obsolete ...
HTMLElement: pointerenter event - Web APIs
bubbles no cancelable no interface pointerevent event handler property onpointerenter examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointerenter', (event) => { console.log('pointer entered element'); }); using the onpointerenter event handler property: const para = document.queryselector('p'); para.onpointerenter = (event) => { console.log('pointer entered element'); }; specifications specification status pointer events obsolete...
HTMLElement: pointerleave event - Web APIs
bubbles no cancelable no interface pointerevent event handler property onpointerleave examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointerleave', (event) => { console.log('pointer left element'); }); using the onpointerleave event handler property: const para = document.queryselector('p'); para.onpointerleave = (event) => { console.log('pointer left element'); }; specifications specification status pointer events obsolete ...
HTMLElement: pointermove event - Web APIs
examples to add a handler for pointermove events using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointermove', (event) => { console.log('pointer moved'); }); you can also use the onpointermove event handler property: const para = document.queryselector('p'); para.onpointermove = (event) => { console.log('pointer moved'); }; specifications specification status pointer events obsolete ...
HTMLElement: pointerout event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerout examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointerout', (event) => { console.log('pointer moved out'); }); using the onpointerout event handler property: const para = document.queryselector('p'); para.onpointerout = (event) => { console.log('pointer moved out'); }; specifications specification status pointer events obsolete ...
HTMLElement: pointerover event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerover examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointerover', (event) => { console.log('pointer moved in'); }); using the onpointerover event handler property: const para = document.queryselector('p'); para.onpointerover = (event) => { console.log('pointer moved in'); }; specifications specification status pointer events obsolete ...
HTMLElement: pointerup event - Web APIs
bubbles yes cancelable yes interface pointerevent event handler property onpointerup examples using addeventlistener(): const para = document.queryselector('p'); para.addeventlistener('pointerup', (event) => { console.log('pointer up'); }); using the onpointerup event handler property: const para = document.queryselector('p'); para.onpointerup = (event) => { console.log('pointer up'); }; specifications specification status pointer events obsolete ...
HTMLElement - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
HTMLFormElement: formdata event - Web APIs
general info bubbles no cancelable no interface formdataevent event handler property globaleventhandlers.onformdata examples // grab reference to form const formelem = document.queryselector('form'); // submit handler formelem.addeventlistener('submit', (e) => { // on form submission, prevent default e.preventdefault(); // construct a formdata object, which fires the formdata event new formdata(formelem); }); // formdata handler to retrieve data formelem.addeventlistener('formdata', (e) => { console.log('formdata fired'); // get the form data from the event object let data = e.formdata; for (var value of data.values...
HTMLFormElement.reportValidity() - Web APIs
syntax htmlformelement.reportvalidity() return value boolean example document.forms['myform'].addeventlistener('submit', function() { document.forms['myform'].reportvalidity(); }, false); specifications specification status comment html living standardthe definition of 'htmlformelement.reportvalidity()' in that specification.
HTMLFormElement - Web APIs
events listen to these events using addeventlistener(), or by assigning an event listener to the oneventname property of this interface.
HTMLImageElement.crossOrigin - Web APIs
const imageurl = "https://mdn.mozillademos.org/files/16797/clock-demo-400px.png"; const container = document.queryselector(".container"); function loadimage(url) { const image = new image(200, 200); image.addeventlistener("load", () => container.prepend(image) ); image.addeventlistener("error", () => { const errmsg = document.createelement("output"); errmsg.value = `error loading image at ${url}`; container.append(errmsg); }); image.crossorigin = "anonymous"; image.alt = ""; image.src = url; } loadimage(imageurl); html <div class="container"> <p>here's a paragraph.
HTMLImageElement.height - Web APIs
var clockimage = document.queryselector("img"); let output = document.queryselector(".size"); const updateheight = event => { output.innertext = clockimage.height; }; window.addeventlistener("load", updateheight); window.addeventlistener("resize", updateheight); result this example may be easier to try out in its own window.
HTMLImageElement.naturalHeight - Web APIs
javascript let output = document.queryselector(".output"); let image = document.queryselector("img"); window.addeventlistener("load", event => { output.innerhtml += `natural size: ${image.naturalwidth} x ` + `${image.naturalheight} pixels<br>`; output.innerhtml += `displayed size: ${image.width} x ` + `${image.height} pixels`; }); the javascript code simply dumps the natural and as-displayed sizes into the <div> with the class output.
HTMLImageElement.naturalWidth - Web APIs
javascript let output = document.queryselector(".output"); let image = document.queryselector("img"); window.addeventlistener("load", event => { output.innerhtml += `natural size: ${image.naturalwidth} x ` + `${image.naturalheight} pixels<br>`; output.innerhtml += `displayed size: ${image.width} x ` + `${image.height} pixels`; }); the javascript code simply dumps the natural and as-displayed sizes into the <div> with the class output.
HTMLImageElement.sizes - Web APIs
let image = document.queryselector("article img"); let break40 = document.getelementbyid("break40"); let break50 = document.getelementbyid("break50"); break40.addeventlistener("click", event => image.sizes = image.sizes.replace(/50em,/, "40em,")); break50.addeventlistener("click", event => image.sizes = image.sizes.replace(/40em,/, "50em,")); result this result may be viewed in its own window here.
HTMLImageElement.width - Web APIs
var clockimage = document.queryselector("img"); let output = document.queryselector(".size"); const updatewidth = event => { output.innertext = clockimage.width; }; window.addeventlistener("load", updatewidth); window.addeventlistener("resize", updatewidth); result this example may be easier to try out in its own window.
HTMLInputElement: invalid event - Web APIs
html <form action="#"> <ul> <li><label>enter an integer between 1 and 10: <input type="number" min="1" max="10" required></label></li> <li><input type="submit" value="submit"></li> </ul> </form><p id="log"></p> javascript const input = document.queryselector('input') const log = document.getelementbyid('log') input.addeventlistener('invalid', logvalue) function logvalue(e) { log.textcontent += e.target.value } result specifications specification status comment html living standardthe definition of 'invalid event' in that specification.
HTMLInputElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <input id="test"/> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const input = document.getelementbyid("test"); for(var i = 0; i < input.labels.length; i++) { console.log(input.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLInputElement: search event - Web APIs
examples // addeventlistener version const input = document.queryselector('input[type="search"]'); input.addeventlistener('search', () => { console.log("the term searched for was " + input.value); }) // onsearch version const input = document.queryselector('input[type="search"]'); input.onsearch = () => { console.log("the term searched for was " + input.value); }) specifications this event is not part of any specifica...
HTMLInputElement.stepDown() - Web APIs
="5" id="thenumber" min="0" max="400"> </label> </p> <p> <label>enter how many values of step you would like to increment by or leave it blank: <input type="number" step="1" id="decrementer" min="-2" max="15"> </label> </p> <input type="button" value="decrement" id="thebutton"> javascript /* make the button call the function */ let button = document.getelementbyid('thebutton'); button.addeventlistener('click', function() { stepondown();} ); function stepondown() { let input = document.getelementbyid('thenumber'); let val = document.getelementbyid('decrementer').value; if (val) { /* increment with a parameter */ input.stepdown(val); } else { /* or without a parameter.
HTMLInputElement.stepUp() - Web APIs
ep="5" id="thenumber" min="0" max="400"> </label> </p> <p> <label>enter how many values of step you would like to increment by or leave it blank: <input type="number" step="1" id="incrementer" min="0" max="25"> </label> </p> <input type="button" value="increment" id="thebutton"> javascript /* make the button call the function */ let button = document.getelementbyid('thebutton') button.addeventlistener('click', function() { steponup() }) function steponup() { let input = document.getelementbyid('thenumber') let val = document.getelementbyid('incrementer').value if (val) { /* increment with a parameter */ input.stepup(val) } else { /* or without a parameter.
HTMLInputElement.webkitEntries - Web APIs
html <input id="files" type="file" multiple> javascript document.getelementbyid("files").addeventlistener("change", function(event) { event.target.webkitentries.foreach(function(entry) { /* do stuff with the entry */ }); }); each time a change event occurs, this code iterates over the selected files, obtaining their filesystementry-based objects and acting on them.
HTMLInputElement.webkitdirectory - Web APIs
html content <input type="file" id="filepicker" name="filelist" webkitdirectory multiple /> <ul id="listing"></ul> javascript content document.getelementbyid("filepicker").addeventlistener("change", function(event) { let output = document.getelementbyid("listing"); let files = event.target.files; for (let i=0; i<files.length; i++) { let item = document.createelement("li"); item.innerhtml = files[i].webkitrelativepath; output.appendchild(item); }; }, false); result specifications specification status comment file and directory e...
HTMLInputElement - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: input fires when the value of an <input>, <select>, or <textarea> element has been changed.
HTMLMediaElement: abort event - Web APIs
bubbles no cancelable no interface event event handler property onabort examples const video = document.queryselector('video'); const videosrc = 'https://path/to/video.webm'; video.addeventlistener('abort', () => { console.log(`abort loading: ${videosrc}`); }); const source = document.createelement('source'); source.setattribute('src', videosrc); source.setattribute('type', 'video/webm'); video.appendchild(source); specifications specification status html living standard living standard html5 recommendation ...
HTMLMediaElement: canplay event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('canplay', (event) => { console.log('video can start, but not sure it will play through.'); }); using the oncanplay event handler property: const video = document.queryselector('video'); video.oncanplay = (event) => { console.log('video can start, but not sure it will play through.'); }; specifications sp...
HTMLMediaElement: canplaythrough event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('canplaythrough', (event) => { console.log('i think i can play through the entire ' + ' video without ever having to stop to buffer.'); }); using the oncanplaythrough event handler property: const video = document.queryselector('video'); video.oncanplaythrough = (event) => { console.log('i think i can play thr...
HTMLMediaElement.captureStream() - Web APIs
document.queryselector('.playandrecord').addeventlistener('click', function() { var playbackelement = document.getelementbyid("playback"); var capturestream = playbackelement.capturestream(); playbackelement.play(); }); see recording a media element for a longer and more intricate example and explanation.
HTMLMediaElement: durationchange event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('durationchange', (event) => { console.log('not sure why, but the duration of the video has changed.'); }); using the ondurationchange event handler property: const video = document.queryselector('video'); video.ondurationchange = (event) => { console.log('not sure why, but the duration of the video has changed.'); ...
HTMLMediaElement: emptied event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('emptied', (event) => { console.log('uh oh.
HTMLMediaElement: ended event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('ended', (event) => { console.log('video stopped either because 1) it was over, ' + 'or 2) no further data is available.'); }); using the onended event handler property: const video = document.queryselector('video'); video.onended = (event) => { console.log('video stopped either because 1) it was over, ' + ...
HTMLMediaElement: error event - Web APIs
bubbles no cancelable no interface event event handler property onerror examples const video = document.queryselector('video'); const videosrc = 'https://path/to/video.webm'; video.addeventlistener('error', () => { console.error(`error loading: ${videosrc}`); }); video.setattribute('src', videosrc); specifications specification status html living standard living standard html5 recommendation ...
HTMLMediaElement: loadeddata event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('loadeddata', (event) => { console.log('yay!
HTMLMediaElement: loadedmetadata event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('loadedmetadata', (event) => { console.log('the duration and dimensions ' + ' of the media and tracks are now known.
HTMLMediaElement: loadstart event - Web APIs
deo { grid-area: video; } .event-log { grid-area: log; } .event-log>label { display: block; } js const loadvideo = document.queryselector('button'); const video = document.queryselector('video'); const eventlog = document.queryselector('.event-log-contents'); let source = null; function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}\n`; } video.addeventlistener('loadstart', handleevent); video.addeventlistener('progress', handleevent); video.addeventlistener('canplay', handleevent); video.addeventlistener('canplaythrough', handleevent); loadvideo.addeventlistener('click', () => { if (source) { document.location.reload(); } else { loadvideo.textcontent = "reset example"; source = document.createelement('source'); ...
HTMLMediaElement.networkState - Web APIs
<audio id="example" preload="auto"> <source src="sound.ogg" type="audio/ogg" /> </audio> var obj = document.getelementbyid('example'); obj.addeventlistener('playing', function() { if (obj.networkstate === 2) { // still loading...
HTMLMediaElement: pause event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('pause', (event) => { console.log('the boolean paused property is now true.
HTMLMediaElement.play() - Web APIs
example this example demonstrates how to confirm that playback has begun and how to gracefully handle blocked automatic playback: let videoelem = document.getelementbyid("video"); let playbutton = document.getelementbyid("playbutton"); playbutton.addeventlistener("click", handleplaybutton, false); playvideo(); async function playvideo() { try { await videoelem.play(); playbutton.classlist.add("playing"); } catch(err) { playbutton.classlist.remove("playing"); } } function handleplaybutton() { if (videoelem.paused) { playvideo(); } else { videoelem.pause(); playbutton.classlist.remove("playing"); } } in this example, p...
HTMLMediaElement: play event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('play', (event) => { console.log('the boolean paused property is now false.
HTMLMediaElement: playing event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('playing', (event) => { console.log('video is no longer paused'); }); using the onplaying event handler property: const video = document.queryselector('video'); video.onplaying = (event) => { console.log('video is no longer paused.'); }; specifications specification status html living stan...
HTMLMediaElement: progress event - Web APIs
grid-area: video; } .event-log { grid-area: log; } .event-log>label { display: block; } javascript const loadvideo = document.queryselector('button'); const video = document.queryselector('video'); const eventlog = document.queryselector('.event-log-contents'); let source = null; function handleevent(event) { eventlog.textcontent = eventlog.textcontent + `${event.type}\n`; } video.addeventlistener('loadstart', handleevent); video.addeventlistener('progress', handleevent); video.addeventlistener('canplay', handleevent); video.addeventlistener('canplaythrough', handleevent); loadvideo.addeventlistener('click', () => { if (source) { document.location.reload(); } else { loadvideo.textcontent = "reset example"; source = document.createelement('source'); ...
HTMLMediaElement: ratechange event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('ratechange', (event) => { console.log('the playback rate changed.'); }); using the onratechange event handler property: const video = document.queryselector('video'); video.onratechange = (event) => { console.log('the playback rate changed.'); }; specifications specification status html livin...
HTMLMediaElement.readyState - Web APIs
<audio id="example" preload="auto"> <source src="sound.ogg" type="audio/ogg" /> </audio> var obj = document.getelementbyid('example'); obj.addeventlistener('loadeddata', function() { if(obj.readystate >= 2) { obj.play(); } }); specifications specification status comment html living standardthe definition of 'htmlmediaelement.readystate' in that specification.
HTMLMediaElement: seeked event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('seeked', (event) => { console.log('video found the playback position it was looking for.'); }); using the onseeked event handler property: const video = document.queryselector('video'); video.onseeked = (event) => { console.log('video found the playback position it was looking for.'); }; specifications s...
HTMLMediaElement: seeking event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('seeking', (event) => { console.log('video is seeking a new position.'); }); using the onseeking event handler property: const video = document.queryselector('video'); video.onseeking = (event) => { console.log('video is seeking a new position.'); }; specifications specification status html li...
HTMLMediaElement: stalled event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('stalled', (event) => { console.log('failed to fetch data, but trying.'); }); using the onstalled event handler property: const video = document.queryselector('video'); video.onstalled = (event) => { console.log('failed to fetch data, but trying.'); }; specifications specification status html ...
HTMLMediaElement: suspend event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('suspend', (event) => { console.log('data loading has been suspended.'); }); using the onsuspend event handler property: const video = document.queryselector('video'); video.onsuspend = (event) => { console.log('data loading has been suspended.'); }; specifications specification status html li...
HTMLMediaElement: timeupdate event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('timeupdate', (event) => { console.log('the currenttime attribute has been updated.
HTMLMediaElement: volumechange event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('volumechange', (event) => { console.log('the volume changed.'); }); using the onvolumechange event handler property: const video = document.queryselector('video'); video.onvolumechange = (event) => { console.log('the volume changed.'); }; specifications specification status html living st...
HTMLMediaElement: waiting event - Web APIs
using addeventlistener(): const video = document.queryselector('video'); video.addeventlistener('waiting', (event) => { console.log('video is waiting for more data.'); }); using the onwaiting event handler property: const video = document.queryselector('video'); video.onwaiting = (event) => { console.log('video is waiting for more data.'); }; specifications specification status html ...
HTMLMediaElement - Web APIs
listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
HTMLMeterElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <meter id="test" min="0" max="100" value="70">70</meter> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const meter = document.getelementbyid("test"); for(var i = 0; i < meter.labels.length; i++) { console.log(meter.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLOutputElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <output id="test">output</output> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const output = document.getelementbyid("test"); for(var i = 0; i < output.labels.length; i++) { console.log(output.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLProgressElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <progress id="test" value="70" max="100">70%</progress> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const progress = document.getelementbyid("test"); for(var i = 0; i < progress.labels.length; i++) { console.log(progress.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLSelectElement.disabled - Web APIs
<label for="drink-select">drink selection:</label> <select id="drink-select" disabled> <option value="1">water</option> <option value="2">beer</option> <option value="3">pepsi</option> <option value="4">whisky</option> </select> javascript var allowdrinkscheckbox = document.getelementbyid("allow-drinks"); var drinkselect = document.getelementbyid("drink-select"); allowdrinkscheckbox.addeventlistener("change", function(event) { if (event.target.checked) { drinkselect.disabled = false; } else { drinkselect.disabled = true; } }, false); result specifications specification status comment html living standardthe definition of 'disabled' in that specification.
HTMLSelectElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <select id="test"> <option value="1">option 1</option> <option value="2">option 2</option> </select> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const select = document.getelementbyid("test"); for(var i = 0; i < select.labels.length; i++) { console.log(select.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLSelectElement.options - Web APIs
example html <label for="test">label</label> <select id="test"> <option value="1">option 1</option> <option value="2">option 2</option> </select> javascript window.addeventlistener("domcontentloaded", function() { const select = document.getelementbyid("test"); for(var i = 0; i < select.options.length; i++) { console.log(select.options[i].label); // "option 1" and "option 2" } }); specifications specification status comment html living standardthe definition of 'options' in that specification.
HTMLSelectElement.selectedIndex - Web APIs
tedindex = index; example html <p id="p">selectedindex: 0</p> <select id="select"> <option selected>option a</option> <option>option b</option> <option>option c</option> <option>option d</option> <option>option e</option> </select> javascript var selectelem = document.getelementbyid('select') var pelem = document.getelementbyid('p') // when a new <option> is selected selectelem.addeventlistener('change', function() { var index = selectelem.selectedindex; // add that data to the <p> pelem.innerhtml = 'selectedindex: ' + index; }) specifications specification status comment html living standardthe definition of 'htmlselectelement' in that specification.
HTMLSelectElement.selectedOptions - Web APIs
javascript the javascript code that establishes the event handler for the button, as well as the event handler itself, looks like this: let orderbutton = document.getelementbyid("order"); let itemlist = document.getelementbyid("foods"); let outputbox = document.getelementbyid("output"); orderbutton.addeventlistener("click", function() { let collection = itemlist.selectedoptions; let output = ""; for (let i=0; i<collection.length; i++) { if (output === "") { output = "your order for the following items has been placed: "; } output += collection[i].label; if (i === (collection.length - 2) && (collection.length < 3)) { output += " and "; } else if (i < (collection.lengt...
HTMLSelectElement - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: input event fires when the value of an <input>, <select>, or <textarea> element has been changed.
HTMLSlotElement.assignedNodes() - Web APIs
let slots = this.shadowroot.queryselectorall('slot'); slots[1].addeventlistener('slotchange', function(e) { let nodes = slots[1].assignednodes(); console.log('element in slot "' + slots[1].name + '" changed to "' + nodes[0].outerhtml + '".'); }); here we grab references to all the slots, then add a slotchange event listener to the 2nd slot in the template — which is the one that keeps having its contents changed in the example.
HTMLSlotElement.name - Web APIs
let slots = this.shadowroot.queryselectorall('slot'); slots[1].addeventlistener('slotchange', function(e) { let nodes = slots[1].assignednodes(); console.log('element in slot "' + slots[1].name + '" changed to "' + nodes[0].outerhtml + '".'); }); here we grab references to all the slots, then add a slotchange event listener to the 2nd slot in the template — which is the one that keeps having its contents changed in the example.
HTMLSlotElement: slotchange event - Web APIs
let slots = this.shadowroot.queryselectorall('slot'); slots[1].addeventlistener('slotchange', function(e) { let nodes = slots[1].assignednodes(); console.log('element in slot "' + slots[1].name + '" changed to "' + nodes[0].outerhtml + '".'); }); here we grab references to all the <slot>s, then add a slotchange event listener to the template's second slot — which is the one which has its contents changed in the example.
HTMLSlotElement - Web APIs
let slots = this.shadowroot.queryselectorall('slot'); slots[1].addeventlistener('slotchange', function(e) { let nodes = slots[1].assignednodes(); console.log('element in slot "' + slots[1].name + '" changed to "' + nodes[0].outerhtml + '".'); }); here we grab references to all the slots, then add a slotchange event listener to the 2nd slot in the template — which is the one that keeps having its contents changed in the example.
HTMLTextAreaElement.labels - Web APIs
example html <label id="label1" for="test">label 1</label> <textarea id="test">some text</textarea> <label id="label2" for="test">label 2</label> javascript window.addeventlistener("domcontentloaded", function() { const textarea = document.getelementbyid("test"); for(var i = 0; i < textarea.labels.length; i++) { console.log(textarea.labels[i].textcontent); // "label 1" and "label 2" } }); specifications specification status comment html living standardthe definition of 'labels' in that specification.
HTMLTextAreaElement - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: input event fires when the value of an <input>, <select>, or <textarea> element has been changed.
HTMLVideoElement.msHorizontalMirror - Web APIs
example var myvideo = document.getelementbyid("videotag1"); myvideo.mshorizontalmirror = true; myvideo.play(); example #2: var flip = document.queryselector('#flip'); flip.addeventlistener('click', function() { video.mshorizontalmirror = true; }); see also htmlvideoelement microsoft api extensions ...
onMSVideoFormatChanged - Web APIs
syntax value description event property object.onmsvideoformatchanged = handler; attachevent method object.attachevent("onmsvideoformatchanged", handler) addeventlistener method object.addeventlistener("", handler, usecapture) event handler parameters val[in], type=function see also htmlvideoelement microsoft api extensions ...
onMSVideoFrameStepCompleted - Web APIs
syntax value description event property object.onmsvideoframestepcompleted = handler; attachevent method object.attachevent("onmsvideoframestepcompleted", handler) addeventlistener method object.addeventlistener("", handler, usecapture) event handler parameters val[in], type=function see also htmlvideoelement microsoft api extensions ...
onMSVideoOptimalLayoutChanged - Web APIs
syntax value description event property object.onmsvideooptimallayoutchanged = handler; attachevent method object.attachevent("onmsvideooptimallayoutchanged", handler) addeventlistener method object.addeventlistener("", handler, usecapture) synchronous no bubbles no cancelable no see also msislayoutoptimalforplayback htmlvideoelement microsoft api extensions ...
HTMLVideoElement.videoHeight - Web APIs
let v = document.getelementbyid("myvideo"); v.addeventlistener("resize", ev => { let w = v.videowidth; let h = v.videoheight; if (w && h) { v.style.width = w; v.style.height = h; } }, false); note that this only applies the change if both the videowidth and the videoheight are non-zero.
HTMLVideoElement.videoWidth - Web APIs
let v = document.getelementbyid("myvideo"); v.addeventlistener("resize", ev => { let w = v.videowidth; let h = v.videoheight; if (w && h) { v.style.width = w; v.style.height = h; } }, false); note that this only applies the change if both the videowidth and the videoheight are non-zero.
HTMLVideoElement - Web APIs
listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
Using microtasks in JavaScript with queueMicrotask() - Web APIs
element.addeventlistener("load", () => console.log("loaded data")); console.log("fetching data..."); element.getdata(); console.log("data fetched"); executing this code twice in a row gives the results shown in the table below: results when data isn't cached (left) vs.
HTML Drag and Drop API - Web APIs
identify what is draggable making an element draggable requires adding the draggable attribute and the ondragstart global event handler, as shown in the following code sample: <script> function dragstart_handler(ev) { // add the target element's id to the data transfer object ev.datatransfer.setdata("text/plain", ev.target.id); } window.addeventlistener('domcontentloaded', () => { // get the element by id const element = document.getelementbyid("p1"); // add the ondragstart event listener element.addeventlistener("dragstart", dragstart_handler); }); </script> <p id="p1" draggable="true">this element is draggable.</p> for more information, see: draggable attribute reference drag operations guide define the drag's data t...
HashChangeEvent.newURL - Web APIs
example window.addeventlistener('hashchange', function(event) { console.log('hash changed to ' + event.newurl); }); specifications specification status comment html living standardthe definition of 'hashchangeevent: newurl' in that specification.
HashChangeEvent.oldURL - Web APIs
example window.addeventlistener('hashchange', function(event) { console.log('hash changed from ' + event.oldurl); }); specifications specification status comment html living standardthe definition of 'hashchangeevent: oldurl' in that specification.
HashChangeEvent - Web APIs
examples syntax options for a hash change you can listen for the hashchange event using any of the following options: window.onhashchange = funcref; or <body onhashchange="funcref();"> or window.addeventlistener("hashchange", funcref, false); basic example function locationhashchanged() { if (location.hash === '#somecoolfeature') { somecoolfeature(); } } window.addeventlistener('hashchange', locationhashchanged); polyfill there are several fallback scripts listed on the modernizr github page.
History.back() - Web APIs
WebAPIHistoryback
html <button id="go-back">go back!</button> javascript document.getelementbyid('go-back').addeventlistener('click', () => { history.back(); }); specifications specification status comment html living standardthe definition of 'history.back()' in that specification.
History.forward() - Web APIs
WebAPIHistoryforward
html <button id='go-forward'>go forward!</button> javascript document.getelementbyid('go-forward').addeventlistener('click', e => { window.history.forward(); }) specifications specification status comment html living standardthe definition of 'history' in that specification.
IDBDatabase: abort event - Web APIs
objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes', 'minutes', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = (event) => { const db = dbopenrequest.result; db.addeventlistener('abort', () => { console.log('transaction aborted'); }); // open a read/write db transaction, ready for adding the data const transaction = db.transaction(['todolist'], 'readwrite'); // abort the transaction transaction.abort(); }; the same example, but assigning the event handler to the onabort property: // open the database const dbopenrequest = window.indexeddb.open('todolis...
IDBDatabase: close event - Web APIs
objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes', 'minutes', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = (event) => { const db = dbopenrequest.result; db.addeventlistener('close', () => { console.log('database connection closed'); }); }; the same example, using the onclose property instead of addeventlistener(): // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.onupgradeneeded = (event) => { const db = event.target.result; // create an objectstore for this database const objectstore = db.createobjectst...
IDBDatabase: error event - Web APIs
', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = (event) => { const newitem = { tasktitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'january', year: 2020 }; const db = dbopenrequest.result; db.addeventlistener('error', () => { console.log(`error adding new item: ${newitem.tasktitle}`); }); // open a read/write db transaction, ready for adding the data const transaction = db.transaction(['todolist'], 'readwrite'); const objectstore = transaction.objectstore('todolist'); const objectstorerequest = objectstore.add(newitem); }; the same example, using the onerror property instead of addeve...
IDBDatabase: versionchange event - Web APIs
' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes', 'minutes', { unique: false }); objectstore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.addeventlistener('success', event => { const db = event.target.result; db.addeventlistener('versionchange', event => { console.log('the version of this database has changed'); }); }); the same example, using the onversionchange event handler property: // open the database const dbopenrequest = window.indexeddb.open('nonexistent', 4); dbopenrequest.onupgradeneeded = event => { const db = event.targ...
IDBDatabase - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
IDBOpenDBRequest: upgradeneeded event - Web APIs
// open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.addeventlistener('upgradeneeded', event => { const db = event.target.result; console.log(`upgrading to version ${db.version}`); // create an objectstore for this database var objectstore = db.createobjectstore('todolist', { keypath: 'tasktitle' }); // define what data items the objectstore will contain objectstore.createindex('hours', 'hours', { unique: false }); objectstore.createindex('minutes',...
IDBOpenDBRequest - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
IDBRequest - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
IDBTransaction: abort event - Web APIs
{ unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = event => { const db = dbopenrequest.result; // open a read/write db transaction, ready for adding the data const transaction = db.transaction(['todolist'], 'readwrite'); // add a listener for `abort` transaction.addeventlistener('abort', () => { console.log('transaction was aborted'); }); // abort the transaction transaction.abort(); }; the same example, but assigning the event handler to the onabort property: // open the database const dbopenrequest = window.indexeddb.open('todolist', 4); dbopenrequest.onupgradeneeded = event => { const db = event.target.result; db.onerror = () => { console.log('...
IDBTransaction: error event - Web APIs
ore.createindex('day', 'day', { unique: false }); objectstore.createindex('month', 'month', { unique: false }); objectstore.createindex('year', 'year', { unique: false }); }; dbopenrequest.onsuccess = (event) => { const db = dbopenrequest.result; // open a read/write db transaction, ready for adding the data const transaction = db.transaction(['todolist'], 'readwrite'); transaction.addeventlistener('error', () => { console.log(`error adding new item: ${newitem.tasktitle}`); }); const objectstore = transaction.objectstore('todolist'); const newitem = { tasktitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'january', year: 2020 }; const objectstorerequest = objectstore.add(newitem); }; the same example, using the onerror property instead of addeventlistener(): // open...
IDBTransaction - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
ImageCapture - Web APIs
o = math.min(canvas.width / img.width, canvas.height / img.height); let x = (canvas.width - img.width * ratio) / 2; let y = (canvas.height - img.height * ratio) / 2; canvas.getcontext('2d').clearrect(0, 0, canvas.width, canvas.height); canvas.getcontext('2d').drawimage(img, 0, 0, img.width, img.height, x, y, img.width * ratio, img.height * ratio); } document.queryselector('video').addeventlistener('play', function() { document.queryselector('#grabframebutton').disabled = false; document.queryselector('#takephotobutton').disabled = false; }); specifications specification status comment mediastream image capturethe definition of 'imagecapture' in that specification.
Basic concepts - Web APIs
they have onsuccess and onerror properties, and you can call addeventlistener() and removeeventlistener() on them.
firesTouchEvents - Web APIs
syntax var boolean = inputdevicecapabilities.firestouchevents returns a boolean example mybutton.addeventlistener('mousedown', function(e) { if (!e.sourcecapabilities.firestouchevents) mybutton.classlist.add("pressed"); }); specifications specification status comment inputdevicecapabilitiesthe definition of 'firetouchevents' in that specification.
InputDeviceCapabilities API - Web APIs
mybutton.addeventlistener('mousedown', function(e) { // touch event case handled above, don't change the style again on tap.
InputEvent.data - Web APIs
WebAPIInputEventdata
<p>some text to copy and paste.</p> <input type="text"> <p class="result"></p> var editable = document.queryselector('input') var result = document.queryselector('.result'); editable.addeventlistener('input', (e) => { result.textcontent = "inputted text: " + e.data; }); specifications specification status comment input events level 2the definition of 'data' in that specification.
InputEvent.dataTransfer - Web APIs
<p><span style="font-style: italic; color: red">exciting: italic red text!</span></p> <p>boring normal text ;-(</p> <hr> <p contenteditable="true">go on, try pasting some content into this editable paragraph and see what happens!</p> <p class="result"></p> var editable = document.queryselector('p[contenteditable]'); var result = document.queryselector('.result') var datatransferobj; editable.addeventlistener('input', (e) => { result.textcontent = e.datatransfer.getdata('text/html'); }); specifications specification status comment input events level 2the definition of 'datatransfer' in that specification.
InputEvent.inputType - Web APIs
try inserting line breaks, or deleting text in different ways, or pasting different content in.</p> <hr> <ul> <li>a sample</li> <li>bulleted</li> <li>list.</li> </ul> <p>another paragraph.</p> </div> javascript const log = document.getelementbyid('log'); const editable = document.queryselector('div[contenteditable]'); editable.addeventlistener('input', loginputtype); function loginputtype(event) { log.textcontent = `input type: ${event.inputtype}`; } result try editing the text inside the <div> and see what happens.
InstallEvent.activeWorker - Web APIs
examples self.addeventlistener('install', function(event) { var myactiveworker = event.activeworker; }); ...
InstallEvent - Web APIs
var cache_version = 1; var current_caches = { prefetch: 'prefetch-cache-v' + cache_version }; self.addeventlistener('install', function(event) { var urlstoprefetch = [ './static/pre_fetched.txt', './static/pre_fetched.html', 'https://www.chromium.org/_/rsrc/1302286216006/config/customlogo.gif' ]; console.log('handling install event.
Timing element visibility with the Intersection Observer API - Web APIs
setting up to set things up, we run the startup() function below when the page loads: window.addeventlistener("load", startup, false); function startup() { contentbox = document.queryselector("main"); document.addeventlistener("visibilitychange", handlevisibilitychange, false); let observeroptions = { root: null, rootmargin: "0px", threshold: [0.0, 0.75] }; adobserver = new intersectionobserver(intersectioncallback, observeroptions); buildcontents(); ref...
KeyboardEvent.charCode - Web APIs
example html <p>type anything into the input box below to log a <code>charcode</code>.</p> <input type="text" /> <p id="log"></p> javascript let input = document.queryselector('input'); let log = document.queryselector('#log'); input.addeventlistener('keypress', function(e) { log.innertext = `key pressed: ${string.fromcharcode(e.charcode)}\ncharcode: ${e.charcode}`; }); result notes in a keypress event, the unicode value of the key pressed is stored in either the keycode or charcode property, but never both.
KeyboardEvent.keyCode - Web APIs
example window.addeventlistener("keydown", function (event) { if (event.defaultprevented) { return; // should do nothing if the default action has been cancelled } var handled = false; if (event.key !== undefined) { // handle the event with keyboardevent.key and set handled true.
LargestContentfulPaint - Web APIs
addeventlistener('visibilitychange', function fn() { if (lcp && document.visibilitystate === 'hidden') { console.log('lcp:', lcp); removeeventlistener('visibilitychange', fn, true); } }, true); } catch (e) { // do nothing if the browser doesn't support this api.
LayoutShift - Web APIs
if (!entry.hadrecentinput) { cumulativelayoutshiftscore += entry.value; } } }); observer.observe({type: 'layout-shift', buffered: true}); document.addeventlistener('visibilitychange', () => { if (document.visibilitystate === 'hidden') { // force any pending records to be dispatched.
LinearAccelerationSensor.x - Web APIs
let lasensor = new linearaccelerationsensor({frequency: 60}); lasensor.addeventlistener('reading', e => { console.log("linear acceleration along the x-axis " + lasensor.x); console.log("linear acceleration along the y-axis " + lasensor.y); console.log("linear acceleration along the z-axis " + lasensor.z); }); lasensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
LinearAccelerationSensor.y - Web APIs
let lasensor = new linearaccelerationsensor({frequency: 60}); lasensor.addeventlistener('reading', e => { console.log("linear acceleration along the x-axis " + lasensor.x); console.log("linear acceleration along the y-axis " + lasensor.y); console.log("linear acceleration along the z-axis " + lasensor.z); }); lasensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
LinearAccelerationSensor.z - Web APIs
let lasensor = new linearaccelerationsensor({frequency: 60}); lasensor.addeventlistener('reading', e => { console.log("linear acceleration along the x-axis " + lasensor.x); console.log("linear acceleration along the y-axis " + lasensor.y); console.log("linear acceleration along the z-axis " + lasensor.z); }); lasensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
LinearAccelerationSensor - Web APIs
let lasensor = new linearaccelerationsensor({frequency: 60}); lasensor.addeventlistener('reading', e => { console.log("linear acceleration along the x-axis " + lasensor.x); console.log("linear acceleration along the y-axis " + lasensor.y); console.log("linear acceleration along the z-axis " + lasensor.z); }); lasensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Location - Web APIs
WebAPILocation
e:40%; line-height:1.5; background:black;} [title]:hover:before, :target:before {background:black; color:yellow;} [title] [title]:before {margin-top:1.5em;} [title] [title] [title]:before {margin-top:3em;} [title]:hover, :target {position:relative; z-index:1; outline:50em solid rgba(255,255,255,.8);} javascript [].foreach.call(document.queryselectorall('[title][id]'), function (node) { node.addeventlistener("click", function(e) { e.preventdefault(); e.stoppropagation(); window.location.hash = '#' + $(this).attr('id'); }); }); [].foreach.call(document.queryselectorall('[title]'), function (node) { node.addeventlistener("click", function(e) { e.preventdefault(); e.stoppropagation(); window.location.hash = ''; }); }); result properties location.ancestororigins is a...
MSCandidateWindowHide - Web APIs
syntax event property object.oncandidatewindowhide = handler; addeventlistener method object.addeventlistener("mscandidatewindowhide", handler, usecapture) nbsp; parameters pevtobj [in] type: ihtmleventobj pointer to an ihtmleventobj interface for the current event.
MSCandidateWindowUpdate - Web APIs
syntax event property object.oncandidatewindowupdate = handler; addeventlistener method object.addeventlistener("mscandidatewindowupdate", handler, usecapture) parameters pevtobj [in] type: ihtmleventobj pointer to an ihtmleventobj interface for the current event.
Magnetometer.x - Web APIs
WebAPIMagnetometerx
let magsensor = new magnetometer({frequency: 60}); magsensor.addeventlistener('reading', e => { console.log("magnetic field along the x-axis " + magsensor.x); console.log("magnetic field along the y-axis " + magsensor.y); console.log("magnetic field along the z-axis " + magsensor.z); }); magsensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Magnetometer.y - Web APIs
WebAPIMagnetometery
let magsensor = new magnetometer({frequency: 60}); magsensor.addeventlistener('reading', e => { console.log("magnetic field along the x-axis " + magsensor.x); console.log("magnetic field along the y-axis " + magsensor.y); console.log("magnetic field along the z-axis " + magsensor.z); }); magsensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Magnetometer.z - Web APIs
WebAPIMagnetometerz
let magsensor = new magnetometer({frequency: 60}); magsensor.addeventlistener('reading', e => { console.log("magnetic field along the x-axis " + magsensor.x); console.log("magnetic field along the y-axis " + magsensor.y); console.log("magnetic field along the z-axis " + magsensor.z); }); magsensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
Magnetometer - Web APIs
let magsensor = new magnetometer({frequency: 60}); magsensor.addeventlistener('reading', e => { console.log("magnetic field along the x-axis " + magsensor.x); console.log("magnetic field along the y-axis " + magsensor.y); console.log("magnetic field along the z-axis " + magsensor.z); }); magsensor.start(); specifications specification status comment generic sensor api candidate recommendation defines sensors in general.
MediaDevices: devicechange event - Web APIs
bubbles no cancelable no interface event event handler ondevicechange example you can use the devicechange event in an addeventlistener method: navigator.mediadevices.addeventlistener('devicechange', function(event) { updatedevicelist(); }); or use the ondevicechange event handler property: navigator.mediadevices.ondevicechange = function(event) { updatedevicelist(); } specifications specification status media capture and streamsthe definition of 'devicechange' in that specification.
MediaDevices.ondevicechange - Web APIs
let videoelement = document.getelementbyid("video"); let logelement = document.getelementbyid("log"); function log(msg) { logelement.innerhtml += msg + "<br>"; } document.getelementbyid("startbutton").addeventlistener("click", function() { navigator.mediadevices.getusermedia({ video: { width: 160, height: 120, framerate: 30 }, audio: { samplerate: 44100, samplesize: 16, volume: 0.25 } }).then(stream => { videoelement.srcobject = stream; updatedevicelist(); }) .catch(err => log(err.name + ": " + err.message)); }, false); we set up glo...
MediaQueryList.matches - Web APIs
examples this example detects viewport orientation changes by creating a media query using the orientation media feature: function addmqlistener(mq, callback) { if (mq.addeventlistener) { mq.addeventlistener("change", callback); } else { mq.addlistener(callback); } } addmqlistener(window.matchmedia("(orientation:landscape)"), event => { if (event.matches) { /* now in landscape orientation */ } else { /* now in portrait orientation */ } } ); specifications specification status comment css object model (cssom...
MediaQueryList.onchange - Web APIs
}; example var mql = window.matchmedia('(max-width: 600px)'); mql.addeventlistener( "change", (e) => { if (e.matches) { /* the viewport is 600 pixels wide or less */ console.log('this is a narrow screen — less than 600px wide.') } else { /* the viewport is more than than 600 pixels wide */ console.log('this is a wide screen — more than 600px wide.') } }) specifications specification status comment css object model (css...
MediaRecorder: error event - Web APIs
examples using addeventlistener to listen for error events: async function record() { const stream = await navigator.mediadevices.getusermedia({audio: true}); const recorder = new mediarecorder(stream); recorder.addeventlistener('error', (event) => { console.error(`error recording stream: ${event.error.name}`) }); recorder.start(); } record(); the same, but using the onerror event handler property...
MediaRecorder.ondataavailable - Web APIs
} mediarecorder.addeventlistener('dataavailable', function(event) { ...
MediaRecorder.onpause - Web APIs
} mediarecorder.addeventlistener('pause', function(event) { ...
MediaRecorder.onresume - Web APIs
} mediarecorder.addeventlistener('resume', function(event) { ...
MediaRecorder.onstart - Web APIs
} mediarecorder.addeventlistener('start', function(event) { ...
MediaRecorder.onstop - Web APIs
} mediarecorder.addeventlistener('stop', function(event) { ...
MediaRecorder.onwarning - Web APIs
} mediarecorder.addeventlistener('warning', function(event) { ...
MediaRecorder - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
MediaSource.MediaSource() - Web APIs
rl = 'frag_bunny.mp4'; // need to be specific for blink regarding codecs // ./mp4info frag_bunny.mp4 | grep codec var mimecodec = 'video/mp4; codecs="avc1.42e01e, mp4a.40.2"'; if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource; //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } ...
MediaSource.activeSourceBuffers - Web APIs
example the following snippet is based on a simple example written by nick desaulniers (view the full demo live, or download the source for further investigation.) function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); console.log(mediasource.activesourcebuffers); // will contain the source buffer that was added above, // as it is selected for playing in the video player video.play(); //console.log(mediasource.readystate); // ended }); sourcebuffer.appendbuffer(buf); }); }; ...
MediaSource.addSourceBuffer() - Web APIs
rl = 'frag_bunny.mp4'; // need to be specific for blink regarding codecs // ./mp4info frag_bunny.mp4 | grep codec var mimecodec = 'video/mp4; codecs="avc1.42e01e, mp4a.40.2"'; if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource; //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); vid...
MediaSource.duration - Web APIs
roperty is true.) example the following snippet is based on a simple example written by nick desaulniers (view the full demo live, or download the source for further investigation.) function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); mediasource.duration = 120; video.play(); //console.log(mediasource.readystate); // ended }); sourcebuffer.appendbuffer(buf); }); }; ...
MediaSource.endOfStream() - Web APIs
rl = 'frag_bunny.mp4'; // need to be specific for blink regarding codecs // ./mp4info frag_bunny.mp4 | grep codec var mimecodec = 'video/mp4; codecs="avc1.42e01e, mp4a.40.2"'; if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource; //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); vid...
MediaSource.isTypeSupported() - Web APIs
rl = 'frag_bunny.mp4'; // need to be specific for blink regarding codecs // ./mp4info frag_bunny.mp4 | grep codec var mimecodec = 'video/mp4; codecs="avc1.42e01e, mp4a.40.2"'; if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource; //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); vid...
MediaSource.readyState - Web APIs
example the following snippet is from a simple example written by nick desaulniers (view the full demo live, or download the source for further investigation.) if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource; //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); vid...
MediaSource.sourceBuffers - Web APIs
example the following snippet is based on a simple example written by nick desaulniers (view the full demo live, or download the source for further investigation.) function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); console.log(mediasource.sourcebuffers); // will contain the source buffer that was added above video.play(); //console.log(mediasource.readystate); // ended }); sourcebuffer.appendbuffer(buf); }); }; ...
MediaSource - Web APIs
= 'frag_bunny.mp4'; // need to be specific for blink regarding codecs // ./mp4info frag_bunny.mp4 | grep codec var mimecodec = 'video/mp4; codecs="avc1.42e01e, mp4a.40.2"'; if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource(); //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); vid...
MediaStream: addtrack event - Web APIs
bubbles no cancelable no interface mediastreamtrackevent event handler property onaddtrack examples using addeventlistener(): let stream = new mediastream(); stream.addeventlistener('addtrack', (event) => { console.log(`new ${event.track.kind} track added`); }); using the onaddtrack event handler property: let stream = new mediastream(); stream.onaddtrack = (event) => { console.log(`new ${event.track.kind} track added`); }; specifications specification status media capture and streamsthe definition of 'addtrack' in that specification.
MediaStream: removetrack event - Web APIs
bubbles no cancelable no interface mediastreamtrackevent event handler property onremovetrack examples using addeventlistener(): let stream = new mediastream(); stream.addeventlistener('removetrack', (event) => { console.log(`${event.track.kind} track removed`); }); using the onremovetrack event handler property: let stream = new mediastream(); stream.onremovetrack = (event) => { console.log(`${event.track.kind} track removed`); }; specifications specification status media capture and streamsthe definition of 'removetrack' in that specification.
MediaStreamTrack: ended event - Web APIs
track.addeventlistener('ended', () => { let statuselem = document.getelementbyid("status-icon"); statuselem.src = "/images/stopped-icon.png"; }) you can also set up the event handler using the mediastreamtrack.onended property: track.onended = function() { let statuselem = document.getelementbyid("status-icon"); statuselem.src = "/images/stopped-icon.png"; } specifications specification status ...
MediaStreamTrack: mute event - Web APIs
musictrack.addeventlistener("mute", event => { document.getelementbyid("timeline-widget").style.backgroundcolor = "#aaa"; }, false); musictrack.addeventlistener("unmute", event => { document.getelementbyid("timeline-widget").style.backgroundcolor = "#fff"; }, false); with these event handlers in place, when the track musictrack enters its muted state, the element with the id timeline-widget gets its background color c...
MediaStreamTrack: unmute event - Web APIs
musictrack.addeventlistener("mute", event => { document.getelementbyid("timeline-widget").style.backgroundcolor = "#aaa"; }, false); musictrack.addeventlistener("unmute", event => { document.getelementbyid("timeline-widget").style.backgroundcolor = "#fff"; }, false); with these event handlers in place, when the track musictrack enters its muted state, the element with the id timeline-widget gets its background color c...
MediaStreamTrack - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: ended sent when playback of the track ends (when the value readystate changes to ended).
Using the Media Capabilities API - Web APIs
= document.getelementbyid("results") li.innerhtml = content; ul.appendchild(li); }).catch((error) => { var li = document.createelement('li'), ul = document.getelementbyid("results"); li.innertext = 'codec ' + mc.videoconfiguration.video.contenttype + ' threw an error: ' + error; ul.appendchild(li); }); } } document.getelementbyid('tryit').addeventlistener('click', mc.tryit); live result ...
Media Session API - Web APIs
the following example adds a pointerup event to an on-page play button, which is then used to kick off the media session code: playbutton.addeventlistener('pointerup', function(event) { var audio = document.queryselector('audio'); // user interacted with the page.
MessageChannel() - Web APIs
var channel = new messagechannel(); var para = document.queryselector('p'); var ifr = document.queryselector('iframe'); var otherwindow = ifr.contentwindow; ifr.addeventlistener("load", iframeloaded, false); function iframeloaded() { otherwindow.postmessage('hello from the main page!', '*', [channel.port2]); } channel.port1.onmessage = handlemessage; function handlemessage(e) { para.innerhtml = e.data; } for a full working example, see our channel messaging basic demo on github (run it live too).
MessageChannel.port1 - Web APIs
var channel = new messagechannel(); var para = document.queryselector('p'); var ifr = document.queryselector('iframe'); var otherwindow = ifr.contentwindow; ifr.addeventlistener("load", iframeloaded, false); function iframeloaded() { otherwindow.postmessage('hello from the main page!', '*', [channel.port2]); } channel.port1.onmessage = handlemessage; function handlemessage(e) { para.innerhtml = e.data; } specifications specification status comment html living standardthe definition of 'port1' in that specification.
MessageChannel.port2 - Web APIs
var channel = new messagechannel(); var para = document.queryselector('p'); var ifr = document.queryselector('iframe'); var otherwindow = ifr.contentwindow; ifr.addeventlistener("load", iframeloaded, false); function iframeloaded() { otherwindow.postmessage('hello from the main page!', '*', [channel.port2]); } channel.port1.onmessage = handlemessage; function handlemessage(e) { para.innerhtml = e.data; } for a full working example, see our channel messaging basic demo on github (run it live too).
MessageChannel - Web APIs
var channel = new messagechannel(); var output = document.queryselector('.output'); var iframe = document.queryselector('iframe'); // wait for the iframe to load iframe.addeventlistener("load", onload); function onload() { // listen for messages on port1 channel.port1.onmessage = onmessage; // transfer port2 to the iframe iframe.contentwindow.postmessage('hello from the main page!', '*', [channel.port2]); } // handle messages received on port1 function onmessage(e) { output.innerhtml = e.data; } for a full working example, see our channel messaging basic demo on ...
MessageEvent.ports - Web APIs
example onconnect = function(e) { var port = e.ports[0]; port.addeventlistener('message', function(e) { var workerresult = 'result: ' + (e.data[0] * e.data[1]); port.postmessage(workerresult); }); port.start(); // required when using addeventlistener.
MessagePort.onmessage - Web APIs
var channel = new messagechannel(); var para = document.queryselector('p'); var ifr = document.queryselector('iframe'); var otherwindow = ifr.contentwindow; ifr.addeventlistener("load", iframeloaded, false); function iframeloaded() { otherwindow.postmessage('hello from the main page!', '*', [channel.port2]); } channel.port1.onmessage = handlemessage; function handlemessage(e) { para.innerhtml = e.data; } for a full working example, see our channel messaging basic demo on github (run it live too).
MessagePort.postMessage() - Web APIs
var channel = new messagechannel(); var para = document.queryselector('p'); var ifr = document.queryselector('iframe'); var otherwindow = ifr.contentwindow; ifr.addeventlistener("load", iframeloaded, false); function iframeloaded() { otherwindow.postmessage('hello from the main page!', '*', [channel.port2]); } channel.port1.onmessage = handlemessage; function handlemessage(e) { para.innerhtml = e.data; } for a full working example, see our channel messaging basic demo on github (run it live too).
MouseEvent.altKey - Web APIs
WebAPIMouseEventaltKey
html <p>click anywhere to test the <code>altkey</code> property.</p> <p id="log"></p> javascript let log = document.queryselector('#log'); document.addeventlistener('click', logkey); function logkey(e) { log.textcontent = `the alt key is pressed: ${e.altkey}`; } result specifications specification status comment document object model (dom) level 3 events specificationthe definition of 'mouseevent.altkey' in that specification.
MouseEvent.button - Web APIs
WebAPIMouseEventbutton
example html <button id="button" oncontextmenu="event.preventdefault();">click here with your mouse...</button> <p id="log"></p> javascript let button = document.queryselector('#button'); let log = document.queryselector('#log'); button.addeventlistener('mouseup', logmousebutton); function logmousebutton(e) { if (typeof e === 'object') { switch (e.button) { case 0: log.textcontent = 'left button clicked.'; break; case 1: log.textcontent = 'middle button clicked.'; break; case 2: log.textcontent = 'right button clicked.'; break; default: log.textcontent = `unkn...
MouseEvent.buttons - Web APIs
html <p>click anywhere with one or more mouse buttons.</p> <pre id="log">buttons: </pre> javascript let log = document.createtextnode('?'); // let log = new text('?'); function logbuttons(e) { log.data = `${e.buttons} (${e.type})`; // log.nodevalue= `${e.buttons} (${e.type})`; } document.addeventlistener('mouseup', logbuttons); document.addeventlistener('mousedown', logbuttons); // document.addeventlistener('mousemove', logbuttons); document.queryselector('#log').appendchild(log) result specifications specification status comment document object model (dom) level 3 events specificationthe definition of 'mouseevent.buttons' in that specification.
MouseEvent.clientX - Web APIs
html <p>move your mouse to see its position.</p> <p id="screen-log"></p> javascript let screenlog = document.queryselector('#screen-log'); document.addeventlistener('mousemove', logkey); function logkey(e) { screenlog.innertext = ` screen x/y: ${e.screenx}, ${e.screeny} client x/y: ${e.clientx}, ${e.clienty}`; } result specifications specification status comment css object model (cssom) view modulethe definition of 'clientx' in that specification.
MouseEvent.clientY - Web APIs
html <p>move your mouse to see its position.</p> <p id="screen-log"></p> javascript let screenlog = document.queryselector('#screen-log'); document.addeventlistener('mousemove', logkey); function logkey(e) { screenlog.innertext = ` screen x/y: ${e.screenx}, ${e.screeny} client x/y: ${e.clientx}, ${e.clienty}`; } result specifications specification status comment css object model (cssom) view modulethe definition of 'clienty' in that specification.
MouseEvent.ctrlKey - Web APIs
html <p>click anywhere to test the <code>ctrlkey</code> property.</p> <p id="log"></p> javascript let log = document.queryselector('#log'); document.addeventlistener('click', logkey); function logkey(e) { log.textcontent = `the ctrl key is pressed: ${e.ctrlkey}`; } result specifications specification status comment document object model (dom) level 3 events specificationthe definition of 'mouseevent.ctrlkey' in that specification.
MouseEvent.metaKey - Web APIs
html <p>click anywhere to test the <code>metakey</code> property.</p> <p id="log"></p> javascript let log = document.queryselector('#log'); document.addeventlistener('click', logkey); function logkey(e) { log.textcontent = `the meta key is pressed: ${e.metakey}`; } result specifications specification status comment document object model (dom) level 3 events specificationthe definition of 'mouseevent.metakey' in that specification.
MouseEvent.movementX - Web APIs
html <p id="log">move your mouse around.</p> javascript function logmovement(event) { log.insertadjacenthtml('afterbegin', `movement: ${event.movementx}, ${event.movementy}<br>`); while (log.childnodes.length > 128) log.lastchild.remove() } const log = document.getelementbyid('log'); document.addeventlistener('mousemove', logmovement); result specifications specification status comment pointer lockthe definition of 'mouseevent.movementx' in that specification.
MouseEvent.movementY - Web APIs
html <p id="log">move your mouse around.</p> javascript function logmovement(event) { log.innertext = `movement: ${event.movementx}, ${event.movementy}\n${log.innertext}`; } const log = document.getelementbyid('log'); document.addeventlistener('mousemove', logmovement); result specifications specification status comment pointer lockthe definition of 'mouseevent.movementy' in that specification.
MouseEvent.pageX - Web APIs
WebAPIMouseEventpageX
javascript var box = document.queryselector(".box"); var pagex = document.getelementbyid("x"); var pagey = document.getelementbyid("y"); function updatedisplay(event) { pagex.innertext = event.pagex; pagey.innertext = event.pagey; } box.addeventlistener("mousemove", updatedisplay, false); box.addeventlistener("mouseenter", updatedisplay, false); box.addeventlistener("mouseleave", updatedisplay, false); the javascript code uses addeventlistener() to register the function updatedisplay() as the event handler for the mousemove, mouseenter, and mouseleave events.
MouseEvent.region - Web APIs
WebAPIMouseEventregion
<canvas id="canvas"></canvas> <script> var canvas = document.getelementbyid("canvas"); var ctx = canvas.getcontext("2d"); ctx.beginpath(); ctx.arc(70, 80, 10, 0, 2 * math.pi, false); ctx.fill(); ctx.addhitregion({id: "circle"}); canvas.addeventlistener("mousemove", function(event){ if(event.region) { console.log("hit region: " + event.region); } }); </script> ...
MouseEvent.relatedTarget - Web APIs
<p id="log"></p> </body> css #outer { width: 250px; height: 125px; display: flex; } #red { flex-grow: 1; background: red; } #blue { flex-grow: 1; background: blue; } #log { max-height: 120px; overflow-y: scroll; } javascript const mouseoutlog = document.getelementbyid('log'), red = document.getelementbyid('red'), blue = document.getelementbyid('blue'); red.addeventlistener('mouseover', overlistener); red.addeventlistener('mouseout', outlistener); blue.addeventlistener('mouseover', overlistener); blue.addeventlistener('mouseout', outlistener); function outlistener(event) { let related = event.relatedtarget ?
MouseEvent.screenX - Web APIs
html <p>move your mouse to see its position.</p> <p id="screen-log"></p> javascript let screenlog = document.queryselector('#screen-log'); document.addeventlistener('mousemove', logkey); function logkey(e) { screenlog.innertext = ` screen x/y: ${e.screenx}, ${e.screeny} client x/y: ${e.clientx}, ${e.clienty}`; } result routing an event when you trap events on the window, document, or other roomy elements, you can get the coordinates of that event (e.g., a click) and route it properly, as the following example demonstrates: function checkclic...
MouseEvent.screenY - Web APIs
html <p>move your mouse to see its position.</p> <p id="screen-log"></p> javascript let screenlog = document.queryselector('#screen-log'); document.addeventlistener('mousemove', logkey); function logkey(e) { screenlog.innertext = ` screen x/y: ${e.screenx}, ${e.screeny} client x/y: ${e.clientx}, ${e.clienty}`; } result specifications specification status comment css object model (cssom) view modulethe definition of 'screeny' in that specification.
MouseEvent.shiftKey - Web APIs
html <p>click anywhere to test the <code>shiftkey</code> property.</p> <p id="log"></p> javascript let log = document.queryselector('#log'); document.addeventlistener('click', logkey); function logkey(e) { log.textcontent = `the shift key is pressed: ${e.shiftkey}`; } result specifications specification status comment document object model (dom) level 3 events specificationthe definition of 'mouseevent.shiftkey' in that specification.
MouseEvent - Web APIs
eevent("click", { bubbles: true, cancelable: true, view: window }); var cb = document.getelementbyid("checkbox"); //element to click on var canceled = !cb.dispatchevent(evt); if(canceled) { // a handler called preventdefault alert("canceled"); } else { // none of the handlers called preventdefault alert("not canceled"); } } document.getelementbyid("button").addeventlistener('click', simulateclick); result specifications specification status comment css object model (cssom) view modulethe definition of 'mouseevent' in that specification.
msPlayToSource - Web APIs
ptm.addeventlistener("sourcerequested", function(e) { // step 3: specify the media to be streamed (to filter devices).
MutationEvent - Web APIs
mutation events list the following is a list of all mutation events, as defined in dom level 3 events specification: domattrmodified domattributenamechanged domcharacterdatamodified domelementnamechanged domnodeinserted domnodeinsertedintodocument domnoderemoved domnoderemovedfromdocument domsubtreemodified usage you can register a listener for mutation events using eventtarget.addeventlistener() as follows: element.addeventlistener("domnodeinserted", function (event) { // ...
Navigator.getBattery() - Web APIs
let batteryischarging = false; navigator.getbattery().then(function(battery) { batteryischarging = battery.charging; battery.addeventlistener('chargingchange', function() { batteryischarging = battery.charging; }); }); for more examples and details, see battery status api.
Navigator.getGamepads() - Web APIs
syntax var gamepads = navigator.getgamepads(); example window.addeventlistener("gamepadconnected", function(e) { var gp = navigator.getgamepads()[e.gamepad.index]; console.log( "gamepad connected at index %d: %s.
Navigator.share() - Web APIs
WebAPINavigatorshare
the javascript looks like this: const sharedata = { title: 'mdn', text: 'learn web development on mdn!', url: 'https://developer.mozilla.org', } const btn = document.queryselector('button'); const resultpara = document.queryselector('.result'); // must be triggered some kind of "user activation" btn.addeventlistener('click', async () => { try { await navigator.share(sharedata) resultpara.textcontent = 'mdn shared successfully' } catch(err) { resultpara.textcontent = 'error: ' + err } }); sharing files to share files, first test for and call navigator.canshare().
Navigator.onLine - Web APIs
to see changes in the network state, use addeventlistener to listen for the events on window.online and window.offline, as in the following example: window.addeventlistener('offline', function(e) { console.log('offline'); }); window.addeventlistener('online', function(e) { console.log('online'); }); specifications specification status comment html living standardthe definition of 'navigator.online' in that specification.
NetworkInformation.downlinkMax - Web APIs
d'; var downlinkmax = 'not supported'; if ('connection' in navigator) { connectiontype = navigator.connection.effectivetype; if ('downlinkmax' in navigator.connection) { downlinkmax = navigator.connection.downlinkmax; } } console.log('current connection type: ' + connectiontype + ' (downlink max: ' + downlinkmax + ')'); } logconnectiontype(); navigator.connection.addeventlistener('change', logconnectiontype); specifications specification status comment network information apithe definition of 'downlinkmax' in that specification.
NetworkInformation.onchange - Web APIs
} // register for event changes: navigator.connection.onchange = changehandler; // another way: navigator.connection.addeventlistener('change', changehandler); specifications specification status comment network information apithe definition of 'onchange' in that specification.
Network Information API - Web APIs
var connection = navigator.connection || navigator.mozconnection || navigator.webkitconnection; var type = connection.effectivetype; function updateconnectionstatus() { console.log("connection type changed from " + type + " to " + connection.effectivetype); type = connection.effectivetype; } connection.addeventlistener('change', updateconnectionstatus); preload large resources the connection object is useful for deciding whether to preload resources that take large amounts of bandwidth or memory.
Node.cloneNode() - Web APIs
WebAPINodecloneNode
it does not copy event listeners added using addeventlistener() or those assigned to element properties (e.g., node.onclick = somefunction).
NotificationAction - Web APIs
self.registration.shownotification("new mail from alice", { actions: [ { action: 'archive', title: 'archive' } ] }); self.addeventlistener('notificationclick', function(event) { event.notification.close(); if (event.action === 'archive') { // archive action was clicked archiveemail(); } else { // main body of notification was clicked clients.openwindow('/inbox'); } }, false); specifications specification status comment notifications api living standard living standard ...
NotificationEvent.action - Web APIs
example self.registration.shownotification("new articles available", { actions: [{action: "get", title: "get now."}] }); self.addeventlistener('notificationclick', function(event) { event.notification.close(); if (event.action === 'get') { synchronizereader(); } else { clients.openwindow("/reader"); } }, false); specifications specification status comment notifications apithe definition of 'action' in that specification.
NotificationEvent.notification - Web APIs
example self.addeventlistener('notificationclick', function(event) { console.log('on notification click'); // data can be attached to the notification so that you // can process it in the notificationclick handler.
NotificationEvent - Web APIs
example self.addeventlistener('notificationclick', function(event) { console.log('on notification click: ', event.notification.tag); event.notification.close(); // this looks to see if the current is already open and // focuses if it is event.waituntil(clients.matchall({ type: "window" }).then(function(clientlist) { for (var i = 0; i < clientlist.length; i++) { var client = clientlist[i]; if (...
Notifications API - Web APIs
this should be done in response to a user gesture, such as clicking a button, for example: btn.addeventlistener('click', function() { let promise = notification.requestpermission(); // wait for permission }) this is not only best practice — you should not be spamming users with notifications they didn't agree to — but going forward browsers will explicitly disallow notifications not triggered in response to a user gesture.
OfflineAudioContext: complete event - Web APIs
lable no default action none interface offlineaudiocompletionevent event handler property offlineaudiocontext.oncomplete examples when processing is complete, you might want to use the oncomplete handler the prompt the user that the audio can now be played, and enable the play button: let offlineaudioctx = new offlineaudiocontext(); offlineaudioctx.addeventlistener('complete', () => { console.log('offline audio processing now complete'); showmodaldialog('song processed and ready to play'); playbtn.disabled = false; }) you can also set up the event handler using the offlineaudiocontext.oncomplete property: let offlineaudioctx = new offlineaudiocontext(); offlineaudioctx.oncomplete = function() { console.log('offline audio processing now complete')...
OfflineAudioContext - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: complete fired when the rendering of an offline audio context is complete.
PageTransitionEvent.persisted - Web APIs
syntax window.addeventlistener('pageshow', function(event) { if (event.persisted) { console.log('page was loaded from cache.'); } }); value a boolean.
PageTransitionEvent - Web APIs
example html <!doctype html> <html> <body> </body> </html> javascript window.addeventlistener('pageshow', myfunction); function myfunction(event) { if (event.persisted) { alert("the page was cached by the browser"); } else { alert("the page was not cached by the browser"); } } specifications specification status comment html living standardthe definition of 'pagetransitionevent' in that specification.
ParentNode.replaceChildren() - Web APIs
const noselect = document.getelementbyid('no'); const yesselect = document.getelementbyid('yes'); const nobtn = document.getelementbyid('to-no'); const yesbtn = document.getelementbyid('to-yes'); yesbtn.addeventlistener('click', () => { const selectedtransferoptions = document.queryselectorall('#no option:checked'); const existingyesoptions = document.queryselectorall('#yes option'); yesselect.replacechildren(...selectedtransferoptions, ...existingyesoptions); }); nobtn.addeventlistener('click', () => { const selectedtransferoptions = document.queryselectorall('#yes option:checked'); const existingnoo...
PaymentRequest: merchantvalidation event - Web APIs
request.addeventlistener("merchantvalidation", event => { event.complete(async () => { const merchantserverurl = window.location.origin + '/validate?url=' + encodeuricomponent(event.validationurl); // get validation data, and complete validation; return await fetch(merchantserverurl).then(response => response.text()); }, false); }; const response = await request.show(); how merchant server handl...
PaymentRequest.onpaymentmethodchange - Web APIs
syntax paymentrequest.addeventlistener('paymentmethodchange', paymentmethodchangeevent => { ...
PaymentRequest.shippingAddress - Web APIs
var payment = new paymentrequest(supportedinstruments, details, options); payment.addeventlistener('shippingaddresschange', function(evt) { evt.updatewith(new promise(function(resolve) { updatedetails(details, request.shippingaddress, resolve); })); }); payment.show().then(function(paymentresponse) { // processing of paymentresponse exerpted for brevity.
PaymentRequest: shippingaddresschange event - Web APIs
const paymentrequest = new paymentrequest(methoddata, details, options); paymentrequest.addeventlistener("shippingaddresschange", event => { let detailsupdate = checkaddress(paymentrequest.shippingaddress); event.updatewith(detailsupate); }, false); const checkaddress = theaddress => { let detailsupdate = {}; // check the address, return a paymentdetailsupdate object // with any changes or errors.
PaymentRequest: shippingoptionchange event - Web APIs
paymentrequest.addeventlistener("shippingoptionchange", event => { const value = calculatenewtotal(paymentrequest.shippingoption); const total = { currency: "eur", label: "total due", value, }; event.updatewith({ total }); }, false); after caling a custom function, calculatenewtotal(), to compute the updated total based on the newly-selected shipping option as specified by the shippingoption.
PaymentResponse: payerdetailchange event - Web APIs
to be corrected if (object.getownpropertynames(errors).length) { await response.retry(errors); } else { // we have a good payment; send the data to the server await fetch("/pay-for-things/", { method: "post", body: response.json() }); response.complete("success"); } }; await response.retry({ payer: { email: "invalid domain.", phone: "invalid number.", }, }); addeventlistener equivalent you could also set up the event handler using the addeventlistener() method: response.addeventlistener("payerdetailchange", async ev => { ...
PaymentResponse.retry() - Web APIs
requestorresponse.addeventlistener(event, async function listener(ev) { const promisetovalidate = validator(requestorresponse); ev.updatewith(promisetovalidate); const errors = await promisetovalidate; if (!errors) { // yay!
PaymentResponse.shippingAddress - Web APIs
var payment = new paymentrequest(supportedinstruments, details, options); request.addeventlistener('shippingaddresschange', function(evt) { evt.updatewith(new promise(function(resolve) { updatedetails(details, request.shippingaddress, resolve); })); }); payment.show().then(function(paymentresponse) { // processing of paymentresponse exerpted for the same of brevity.
PaymentResponse.shippingOption - Web APIs
var payment = new paymentrequest(supportedinstruments, details, options); request.addeventlistener('shippingoptionchange', function(evt) { evt.updatewith(new promise(function(resolve, reject) { updatedetails(details, request.shippingoption, resolve, reject); })); }); payment.show().then(function(paymentresponse) { // processing of paymentresponse exerpted for the same of brevity.
PaymentResponse - Web APIs
events listen to this event using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
Performance: resourcetimingbufferfull event - Web APIs
function buffer_full(event) { console.log("warning: resource timing buffer is full!"); performance.setresourcetimingbuffersize(200); } function init() { // set a callback if the resource buffer becomes filled performance.onresourcetimingbufferfull = buffer_full; } <body onload="init()"> note that you could also set up the handler using the addeventlistener() function: performance.addeventlistener('resourcetimingbufferfull', buffer_full); specifications specification status comment resource timing level 1the definition of 'onresourcetimingbufferfull' in that specification.
Performance - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
PerformanceEventTiming - Web APIs
0 : infinity; document.addeventlistener('visibilitychange', (event) => { firsthiddentime = math.min(firsthiddentime, event.timestamp); }, {once: true}); // sends the passed data to an analytics endpoint.
PermissionStatus.onchange - Web APIs
} permissionstatus.addeventlistener('change', function() { ...
PointerEvent.isPrimary - Web APIs
target.addeventlistener('pointerdown', function(event) { if (event.isprimary) process_primary_pointer(event); else process_secondary_pointer(event); }, false); specifications specification status comment pointer events – level 2the definition of 'isprimary' in that specification.
PointerEvent.pointerId - Web APIs
let id; // let's assume that this is a previously saved pointerid target.addeventlistener('pointerdown', function(event) { // compare previous event's id that was cached // to current event's id and handle accordingly if (id === event.pointerid) process_event(event); }, false); specifications specification status comment pointer events – level 2the definition of 'pointerid' in that specification.
PointerEvent.pointerType - Web APIs
targetelement.addeventlistener('pointerdown', function(event) { // call the appropriate pointer type handler switch (event.pointertype) { case 'mouse': process_pointer_mouse(event); break; case 'pen': process_pointer_pen(event); break; case 'touch': process_pointer_touch(event); break; default: console.log(`pointertype ${event.pointertype} is not suported`); } }, ...
PointerEvent.pressure - Web APIs
someelement.addeventlistener('pointerdown', function(event) { if (event.pressure == 0) { // no pressure process_no_pressure(event); } else if (event.pressure == 1) { // maximum pressure process_max_pressure(event); } else { // default process_pressure(event); } }, false); specifications specification status comment pointer events – level 2the definition of 'pressur...
PointerEvent.tangentialPressure - Web APIs
someelement.addeventlistener('pointerdown', function(event) { if (event.tangentialpressure == 0) { // no pressure process_no_tanpressure(event); } else if (event.tangentialpressure == 1) { // maximum pressure process_max_tanpressure(event); } else { // default process_tanpressure(event); } }, false); specifications specification status comment pointer events – leve...
PointerEvent.tiltX - Web APIs
someelement.addeventlistener("pointerdown", function(event) { process_tilt(event.tiltx, event.tilty); }, false); specifications specification status comment pointer events – level 2the definition of 'tiltx' in that specification.
PointerEvent.tiltY - Web APIs
someelement.addeventlistener("pointerdown", function(event) { process_tilt(event.tiltx, event.tilty); }, false); specifications specification status comment pointer events – level 2the definition of 'tilty' in that specification.
PointerEvent.twist - Web APIs
someelement.addeventlistener('pointerdown', function(event) { if (event.twist == 0) { // no twist process_no_twist(event); } else { // default process_twist(event); } }, false); specifications specification status comment pointer events – level 2the definition of 'twist' in that specification.
PointerEvent.width - Web APIs
target.addeventlistener("pointerdown", function(ev) { // calculate the contact area var area = ev.width * ev.height; }, false); specifications specification status comment pointer events – level 2the definition of 'width' in that specification.
Using Pointer Events - Web APIs
function startup() { var el = document.getelementsbytagname("canvas")[0]; el.addeventlistener("pointerdown", handlestart, false); el.addeventlistener("pointerup", handleend, false); el.addeventlistener("pointercancel", handlecancel, false); el.addeventlistener("pointermove", handlemove, false); log("initialized."); } this simply sets up all the event listeners for our <canvas> element so we can handle the touch events as they occur.
PushManager.subscribe() - Web APIs
console.log(error); } ); }); responding to user gestures subscribe() calls should be done in response to a user gesture, such as clicking a button, for example: btn.addeventlistener('click', function() { serviceworkerregistration.pushmanager.subscribe(options) .then(function(pushsubscription) { // handle subscription }); }) this is not only best practice — you should not be spamming users with notifications they didn't agree to — but going forward browsers will explicitly disallow notifications not triggered in response to a user gesture.
PushMessageData.arrayBuffer() - Web APIs
examples self.addeventlistener('push', function(event) { var buffer = event.data.arraybuffer(); // do something with your array buffer }); specifications specification status comment push apithe definition of 'arraybuffer()' in that specification.
PushMessageData.blob() - Web APIs
examples self.addeventlistener('push', function(event) { var blob = event.data.blob(); // do something with your blob }); specifications specification status comment push apithe definition of 'blob()' in that specification.
PushMessageData.json() - Web APIs
examples self.addeventlistener('push', function(event) { var mydata = event.data.json(); // do something with your data }); specifications specification status comment push apithe definition of 'json()' in that specification.
PushMessageData.text() - Web APIs
examples self.addeventlistener('push', function(event) { var textobj = event.data.text(); // do something with your text }); specifications specification status comment push apithe definition of 'text()' in that specification.
PushMessageData - Web APIs
examples self.addeventlistener('push', function(event) { var obj = event.data.json(); if(obj.action === 'subscribe' || obj.action === 'unsubscribe') { firenotification(obj, event); port.postmessage(obj); } else if(obj.action === 'init' || obj.action === 'chatmsg') { port.postmessage(obj); } }); specifications specification status comment push apithe definition of 'pushmessagedata'...
RTCDTMFSender: tonechange event - Web APIs
this can be done using addeventlistener(): dtmfsender.addeventlistener("tonechange", ev => { let tone = ev.tone; if (tone === "") { tone = "&lt;none&gt;"; } document.getelementbyid("playingtone").innertext = tone; }, false); you can also just set the ontonechange event handler property directly: dtmfsender.ontonechange = function( ev ) { let tone = ev.tone; if (tone === "") { tone = "&lt;none&gt;" } docume...
RTCDTMFSender - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
RTCDTMFToneChangeEvent - Web APIs
dtmfsender.addeventlistener("change", function(event) { if (event.tone !== "") { dialstringbox.innertext += event.tone; } else { senddtmfbutton.disabled = false; } }, false); specifications specification status comment webrtc 1.0: real-time communication between browsersthe definition of 'rtcdtmftonechangeevent' in that specification.
RTCDataChannel.bufferedAmountLowThreshold - Web APIs
listeners may be added with onbufferedamountlow or addeventlistener().
RTCDataChannel: bufferedamountlow event - Web APIs
let pc = new rtcpeerconnection(); let dc = pc.createdatachannel("sendfile"); let source = /* source data object */ dc.bufferedamountlowthreshold = 65536; pc.addeventlistener("bufferedamountlow", ev => { if (source.position <= source.length) { dc.send(source.readfile(65536)); } }, false); after creating the rtcpeerconnection, this calls rtcpeerconnection.createdatachannel() to create the data channel.
RTCDataChannel: close event - Web APIs
dc.addeventlistener("close", ev => { messageinputbox.disabled = true; sendbutton.disabled = true; connectbutton.disabled = false; disconnectbutton.disabled = true; }, false); all this code does in response to receiving the close event is to disable an input box and its "send" button, and to enable the button used to start a call (while disabling the one that ends a call).
RTCDataChannel: error event - Web APIs
"stale cookie error", "sender is out of resource (i.e., memory)", "unable to resolve address", "unrecognized sctp chunk type received", "invalid mandatory parameter", "unrecognized parameters", "no user data (sctp data chunk has no data)", "cookie received while shutting down", "restart of an association with new addresses", "user-initiated abort", "protocol violation" ]; dc.addeventlistener("error", ev => { const err = ev.error; console.error("webrtc error: ", err.message); // handle specific error detail types switch(err.errordetail) { case "sdp-syntax-error": console.error(" sdp syntax error in line ", err.sdplinenumber); break; case "idp-load-failure": console.error(" identity provider load failure: http error ", err.
RTCDataChannel: message event - Web APIs
dc.addeventlistener("message", ev => { let newparagraph = document.createelement("p"); let textnode = document.createtextnode(event.data); newparagraph.appendchild(textnode); document.body.appendchild(newparagraph); }, false); lines 2-4 create the new paragraph element and add the message data to it as a new text node.
RTCDataChannel: open event - Web APIs
dc.addeventlistener("open", ev => { messageinputbox.disabled = false; sendmessagebutton.disabled = false; disconnectbutton.disabled = false; connectbutton.disabled = true; messageinputbox.focus(); }, false); this can also be done by directly setting the value of the channel's onopen event handler property.
RTCIceTransport: gatheringstatechange event - Web APIs
here, the addeventlistener() method is called to add a listener for gatheringstatechange events: pc.getsenders().foreach(sender => { sender.transport.icetransport.addeventlistener("gatheringstatechange", ev => { let transport = ev.target; if (transport.gatheringstate === "complete") { /* this transport has finished gathering candidates, but others may still be working on it */ } }, false); likewise, y...
RTCIceTransport: selectedcandidatepairchange event - Web APIs
let icetransport = pc.getsenders[0].transport.icetransport; let localprotoelem = document.getelementbyid("local-protocol"); let remoteprotoelem = document.getelementbyid("remote-protocol"); icetransport.addeventlistener("selectedcandidatepairchange", ev => { let pair = icetransport.getselectedcandidatepair(); localprotoelem.innertext = pair.local.protocol.touppercase(); remoteprotoelem.innertext = pair.remote.protocol.touppercase(); }, false) this can also be done by setting the onselectedcandidatepairchange event handler property directly.
RTCIceTransport: statechange event - Web APIs
let icetransport = pc.getsenders()[0].transport.icetransport; icetransport.addeventlistener("statechange", ev => { if (icetransport.state === "failed") { handlefailure(pc); } }, false); the same code, using the onstatechange event handler property, looks like this: let icetransport = pc.getsenders()[0].transport.icetransport; icetransport.onstatechange = ev => { if (icetransport.state === "failed") { handlefailure(pc); } }; specifications specification...
RTCIceTransport - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
RTCPeerConnection: addstream event - Web APIs
you can also use the addeventlistener() method to set an event listener: pc.addeventlistener("addstream", ev => doaddstream(ev.stream), false); ...
RTCPeerConnection.canTrickleIceCandidates - Web APIs
pc.setremotedescription(remoteoffer) .then(_ => pc.createanswer()) .then(answer => pc.setlocaldescription(answer)) .then(_ => if (pc.cantrickleicecandidates) { return pc.localdescription; } return new promise(r => { pc.addeventlistener('icegatheringstatechange', e => { if (e.target.icegatheringstate === 'complete') { r(pc.localdescription); } }); }); }) .then(answer => sendanswertopeer(answer)) // signaling message .catch(e => handleerror(e)); pc.addeventlistener('icecandidate', e => { if (pc.cantrickleicecandidates) { sendcandidatetopeer(e.candidate); // signaling message } })...
RTCPeerConnection: connectionstatechange event - Web APIs
nnected": setonlinestatus("online"); break; case "disconnected": setonlinestatus("disconnecting..."); break; case "closed": setonlinestatus("offline"); break; case "failed": setonlinestatus("error"); break; default: setonlinestatus("unknown"); break; } } you can also create a handler for connectionstatechange by using addeventlistener(): pc.addeventlistener("connectionstatechange", ev => { switch(pc.connectionstate) { /* ...
RTCPeerConnection: datachannel event - Web APIs
pc.addeventlistener("datachannel", ev => { receivechannel = ev.channel; receivechannel.onmessage = myhandlemessage; receivechannel.onopen = myhandleopen; receivechannel.onclose = myhandleclose; }, false); receivechannel is set to the value of the event's channel property, which specifies the rtcdatachannel object representing the data channel linking the remote peer to the local one.
RTCPeerConnection: icegatheringstatechange event - Web APIs
pc.onicegatheringstatechange = ev => { let connection = ev.target; switch(connection.icegatheringstate) { case "gathering": /* collection of candidates has begun */ break; case "complete": /* collection of candidates is finished */ break; } } likewise, you can use addeventlistener() to add a listener for icegatheringstatechange events: pc.addeventlistener("icegatheringstatechange", ev => { let connection = ev.target; switch(connection.icegatheringstate) { case "gathering": /* collection of candidates has begun */ break; case "complete": /* collection of candidates is finished */ break; } }, false); specifications specifica...
RTCPeerConnection: icecandidateerror event - Web APIs
pc.addeventlistener("icecandidateerror", (event) => { if (event.errorcode === 701) { reportconnectfail(event.url, event.errortext); } }); note that if multiple stun and/or turn servers are provided when creating the connection, this error may happen more than once, if more than one of those servers fails.
RTCPeerConnection.onaddstream - Web APIs
pc.onaddstream = function(event) { document.getelementbyid("received_video").srcobject = event.stream; document.getelementbyid("hangup-button").disabled = false; }; you can also use addeventlistener() to add a handler for addstream events to an rtcpeerconnection.
RTCPeerConnection.onsignalingstatechange - Web APIs
you may also, as always, set up a handler for the signalingstatechange event using addeventlistener(): myrtcpeerconnection.addeventlistener("signalingstatechange", mysignalingstatechangehandler); or, using an anonymous (inline) handler: myrtcpeerconnection.addeventlistener("signalingstatechange", event => { /* handle the event here */ }); example this snippet shows a handler for signalingstatechange that looks for the "have-local-pranswer" signaling state—indicating that a remote offe...
RTCPeerConnection.removeStream() - Web APIs
example var pc, videostream; navigator.getusermedia({video: true}, function(stream) { pc = new rtcpeerconnection(); videostream = stream; pc.addstream(stream); } document.getelementbyid("closebutton").addeventlistener("click", function(event) { pc.removestream(videostream); pc.close(); }, false); ...
RTCPeerConnection.removeTrack() - Web APIs
var pc, sender; navigator.getusermedia({video: true}, function(stream) { pc = new rtcpeerconnection(); var track = stream.getvideotracks()[0]; sender = pc.addtrack(track, stream); }); document.getelementbyid("closebutton").addeventlistener("click", function(event) { pc.removetrack(sender); pc.close(); }, false); specifications specification status comment webrtc 1.0: real-time communication between browsersthe definition of 'rtcpeerconnection.removetrack()' in that specification.
RTCPeerConnection.restartIce() - Web APIs
pc.addeventlistener("iceconnectionstatechange", event => { if (pc.iceconnectionstate === "failed") { /* possibly reconfigure the connection in some way here */ /* then request ice restart */ pc.restartice(); } }); with this code in place, a transition to the failed state during ice negotiation will cause a negotiationneeded event to be fired, in response to which your code should renegotiate as usu...
RTCPeerConnection.setLocalDescription() - Web APIs
pc.addeventlistener("negotiationneeded", async (event) => { await pc.setlocaldescription(); signalremotepeer({ description: pc.localdescription }); }); other than error handling, that's about it!
RTCPeerConnection: signalingstatechange event - Web APIs
pc.addeventlistener("signalingstatechange", ev => { switch(pc.signalingstate) { case "stable": updatestatus("ice negotiation complete"); break; } }, false); using onsignalingstatechange, it looks like this: pc.onsignalingstatechange = ev => { switch(pc.signalingstate) { case "stable": updatestatus("ice negotiation complete"); break; } }; specifications specific...
RTCPeerConnection - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
RTCPeerConnectionIceErrorEvent.address - Web APIs
pc.addeventlistener("icecandidateerror", (event) => { let networkinfo = `[local interface: ${event.address}:${event.port}`; let iceserverinfo = `[ice server: ${event.url}`; showmessage(errortext, iceserverinfo, networkinfo); }); specifications specification status comment webrtc 1.0: real-time communication between browsersthe definition of 'rtcpeerconnectioniceerrorevent.address' in...
Range.commonAncestorContainer - Web APIs
.highlight { animation: highlight linear 1s; } @keyframes highlight { from { outline: 1px solid #f00f; } to { outline: 1px solid #f000; } } body { padding: 1px; } javascript document.addeventlistener('pointerup', e => { const selection = window.getselection(); if (selection.type === 'range') { for (let i = 0; i < selection.rangecount; i++) { const range = selection.getrangeat(i); playanimation(range.commonancestorcontainer); } } }); function playanimation(el) { if (el.nodetype === node.text_node) { el = el.parentnode; } el.classlist.remove('highlight'); ...
Range.extractContents() - Web APIs
ap">swap selected item(s)</button> <p id="list2">abcdef</p> css body { pointer-events: none; } p { border: 1px solid; font-size: 2em; padding: .3em; } button { font-size: 1.2em; padding: .5em; pointer-events: auto; } javascript const list1 = document.getelementbyid('list1'); const list2 = document.getelementbyid('list2'); const button = document.getelementbyid('swap'); button.addeventlistener('click', e => { selection = window.getselection(); for (let i = 0; i < selection.rangecount; i++) { const range = selection.getrangeat(i); if (range.commonancestorcontainer === list1 || range.commonancestorcontainer.parentnode === list1) { const documentfragment = range.extractcontents(); list2.appendchild(documentfragment); } else if (range.commonancestorcon...
Range.selectNodeContents() - Web APIs
="p"><b>use the buttons below</b> to select or deselect the contents of this paragraph.</p> <button id="select-button">select paragraph</button> <button id="deselect-button">deselect paragraph</button> javascript const p = document.getelementbyid('p'); const selectbutton = document.getelementbyid('select-button'); const deselectbutton = document.getelementbyid('deselect-button'); selectbutton.addeventlistener('click', e => { // clear any current selection const selection = window.getselection(); selection.removeallranges(); // select paragraph const range = document.createrange(); range.selectnodecontents(p); selection.addrange(range); }); deselectbutton.addeventlistener('click', e => { const selection = window.getselection(); selection.removeallranges(); }); result specificati...
ReadableStream.ReadableStream() - Web APIs
const stream = new readablestream({ start(controller) { interval = setinterval(() => { let string = randomchars(); // add the string to the stream controller.enqueue(string); // show it on the screen let listitem = document.createelement('li'); listitem.textcontent = string; list1.appendchild(listitem); }, 1000); button.addeventlistener('click', function() { clearinterval(interval); fetchstream(); controller.close(); }) }, pull(controller) { // we don't really need a pull in this example }, cancel() { // this is called if the reader cancels, // so we should stop generating strings clearinterval(interval); } }); specifications specification status comment s...
ReadableStreamDefaultController.close() - Web APIs
const stream = new readablestream({ start(controller) { interval = setinterval(() => { let string = randomchars(); // add the string to the stream controller.enqueue(string); // show it on the screen let listitem = document.createelement('li'); listitem.textcontent = string; list1.appendchild(listitem); }, 1000); button.addeventlistener('click', function() { clearinterval(interval); fetchstream(); controller.close(); }) }, pull(controller) { // we don't really need a pull in this example }, cancel() { // this is called if the reader cancels, // so we should stop generating strings clearinterval(interval); } }); specifications specification status comment s...
ReadableStreamDefaultController.enqueue() - Web APIs
const stream = new readablestream({ start(controller) { interval = setinterval(() => { let string = randomchars(); // add the string to the stream controller.enqueue(string); // show it on the screen let listitem = document.createelement('li'); listitem.textcontent = string; list1.appendchild(listitem); }, 1000); button.addeventlistener('click', function() { clearinterval(interval); fetchstream(); controller.close(); }) }, pull(controller) { // we don't really need a pull in this example }, cancel() { // this is called if the reader cancels, // so we should stop generating strings clearinterval(interval); } }); specifications specification status comment s...
ReadableStreamDefaultController - Web APIs
const stream = new readablestream({ start(controller) { interval = setinterval(() => { let string = randomchars(); // add the string to the stream controller.enqueue(string); // show it on the screen let listitem = document.createelement('li'); listitem.textcontent = string; list1.appendchild(listitem); }, 1000); button.addeventlistener('click', function() { clearinterval(interval); fetchstream(); controller.close(); }) }, pull(controller) { // we don't really need a pull in this example }, cancel() { // this is called if the reader cancels, // so we should stop generating strings clearinterval(interval); } }); specifications specification status comment s...
ResizeObserver.disconnect() - Web APIs
examples btn.addeventlistener('click', () => { resizeobserver.disconnect(); }) specifications specification status comment resize observerthe definition of 'disconnect()' in that specification.
ResizeObserver.unobserve() - Web APIs
lem.style.fontsize = math.max(1.5, entry.contentboxsize.inlinesize/200) + 'rem'; pelem.style.fontsize = math.max(1, entry.contentboxsize.inlinesize/600) + 'rem'; } else { h1elem.style.fontsize = math.max(1.5, entry.contentrect.width/200) + 'rem'; pelem.style.fontsize = math.max(1, entry.contentrect.width/600) + 'rem'; } } }); resizeobserver.observe(divelem); checkbox.addeventlistener('change', () => { if(checkbox.checked) { resizeobserver.observe(divelem); } else { resizeobserver.unobserve(divelem); } }); specifications specification status comment resize observerthe definition of 'unobserve()' in that specification.
SVGAnimationElement: beginEvent event - Web APIs
roke-width="1"> <animatemotion path="m 0 0 h 300 z" dur="5s" repeatcount="indefinite" /> </circle> </svg> <hr> <ul> </ul> ul { height: 100px; border: 1px solid #ddd; overflow-y: scroll; padding: 10px 30px; } let svgelem = document.queryselector('svg'); let animateelem = document.queryselector('animatemotion'); let list = document.queryselector('ul'); animateelem.addeventlistener('beginevent', () => { let listitem = document.createelement('li'); listitem.textcontent = 'beginevent fired'; list.appendchild(listitem); }) animateelem.addeventlistener('repeatevent', (e) => { let listitem = document.createelement('li'); let msg = 'repeatevent fired'; if(e.detail) { msg += '; repeat number: ' + e.detail; } listitem.textcontent = msg; list.appendchild(listi...
SVGAnimationElement: repeatEvent event - Web APIs
troke-width="1"> <animatemotion path="m 0 0 h 300 z" dur="5s" repeatcount="indefinite" /> </circle> </svg> <hr> <ul> </ul> ul { height: 100px; border: 1px solid #ddd; overflow-y: scroll; padding: 10px 30px; } let svgelem = document.queryselector('svg'); let animateelem = document.queryselector('animatemotion'); let list = document.queryselector('ul'); animateelem.addeventlistener('beginevent', () => { let listitem = document.createelement('li'); listitem.textcontent = 'beginevent fired'; list.appendchild(listitem); }) animateelem.addeventlistener('repeatevent', (e) => { let listitem = document.createelement('li'); let msg = 'repeatevent fired'; if(e.detail) { msg += '; repeat number: ' + e.detail; } listitem.textcontent = msg; list.appendchild(listi...
SVGAnimationElement - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the on...
SVGElement: abort event - Web APIs
bubbles no cancelable no interface svgevent event handler property onabort examples svgelem.addeventlistener('abort', () => { console.log('load aborted.'); }) specifications not really described anywhere specifically, but mentioned in the svg 2 spec.
SVGElement: error event - Web APIs
bubbles yes cancelable no interface svgevent event handler property onerror examples svgelem.addeventlistener('error', () => { console.log('svg not loaded properly.'); }) specifications specification status comment scalable vector graphics (svg) 2the definition of 'error' in that specification.
SVGElement: load event - Web APIs
bubbles no cancelable no interface svgevent event handler property onload examples svgelem.addeventlistener('load', () => { console.log('svg loaded.'); }) specifications specification status comment scalable vector graphics (svg) 2the definition of 'load' in that specification.
SVGElement: resize event - Web APIs
bubbles no cancelable no interface svgevent event handler property onresize examples svgelem.addeventlistener('resize', () => { console.log('svg resized.'); }) specifications specification status comment scalable vector graphics (svg) 2the definition of 'event changes in svg2' in that specification.
SVGElement: scroll event - Web APIs
bubbles no cancelable no interface svgevent event handler property onscroll examples svgelem.addeventlistener('scroll', () => { console.log('svg scrolled.'); }) specifications specification status comment scalable vector graphics (svg) 2the definition of 'event changes in svg2' in that specification.
SVGElement: unload event - Web APIs
bubbles no cancelable no interface svgevent event handler property onunload examples svgelem.addeventlistener('unload', () => { console.log('svg unloaded.'); }) specifications specification status comment scalable vector graphics (svg) 2the definition of 'unload' in that specification.
SVGElement: zoom event - Web APIs
bubbles yes cancelable no interface svgevent event handler property onzoom examples svgelem.addeventlistener('zoom', () => { console.log('svg zoomed.'); }) ...
SVGElement - Web APIs
methods this interface has no methods, but inherits methods from: documentandelementeventhandlers, element, elementcssinlinestyle, globaleventhandlers, htmlorforeignelement, svgelementinstance events listen to these events using addeventlistener() or by assigning an event listener to the equivalent on...
SVGGraphicsElement: copy event - Web APIs
<text x="5" y="10" id="text-to-copy">copy this text</text> <foreignobject x="5" y="20" width="90" height="20"> <input xmlns="http://www.w3.org/1999/xhtml" placeholder="paste it here"/> </foreignobject> </svg> css input { font-size: 10px; width: 100%; height: 90%; box-sizing: border-box; border: 1px solid black; } javascript document.getelementsbytagname("text")[0].addeventlistener("copy", evt => { evt.clipboarddata.setdata('text/plain', document.getselection().tostring().touppercase()); evt.preventdefault(); }); result specifications specification status comment scalable vector graphics (svg) 2 candidate recommendation definition that the clipboard events apply to svg elements.
SVGGraphicsElement: paste event - Web APIs
="-10" width="90" height="20"> <input xmlns="http://www.w3.org/1999/xhtml" value="copy this text"/> </foreignobject> <text x="5" y="30" id="element-to-paste-text" tabindex="1">paste it here</text> </svg> css input { font-size: 10px; width: 100%; height: 90%; box-sizing: border-box; border: 1px solid black; } javascript document.getelementbyid("element-to-paste-text").addeventlistener("paste", evt => { evt.target.textcontent = evt.clipboarddata.getdata("text/plain").touppercase(); evt.preventdefault(); }); result specifications specification status comment scalable vector graphics (svg) 2 candidate recommendation definition that the clipboard events apply to svg elements.
Screen - Web APIs
WebAPIScreen
methods screen.lockorientation lock the screen orientation (only works in fullscreen or for installed apps) screen.unlockorientation unlock the screen orientation (only works in fullscreen or for installed apps) methods inherited from eventtarget: eventtarget.addeventlistener() registers an event handler of a specific event type on the eventtarget.
ScreenOrientation.onchange - Web APIs
syntax screenorientation.addeventlistener('change', function(e) { ...
Using the Screen Capture API - Web APIs
const videoelem = document.getelementbyid("video"); const logelem = document.getelementbyid("log"); const startelem = document.getelementbyid("start"); const stopelem = document.getelementbyid("stop"); // options for getdisplaymedia() var displaymediaoptions = { video: { cursor: "always" }, audio: false }; // set event listeners for the start and stop buttons startelem.addeventlistener("click", function(evt) { startcapture(); }, false); stopelem.addeventlistener("click", function(evt) { stopcapture(); }, false); logging content to make logging of errors and other issues easy, this example overrides certain console methods to output their messages to the <pre> block whose id is log.
ScriptProcessorNode: audioprocess event - Web APIs
bubbles no cancelable no default action none interface audioprocessingevent event handler property scriptprocessornode.onaudioprocess examples scriptnode.addeventlistener('audioprocess', function(audioprocessingevent) { // the input buffer is a song we loaded earlier var inputbuffer = audioprocessingevent.inputbuffer; // the output buffer contains the samples that will be modified and played var outputbuffer = audioprocessingevent.outputbuffer; // loop through the output channels (in this case there is only one) for (var channel = 0; channel < outputbuffer.numberofchannels; channel++) ...
ScriptProcessorNode - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface: audioprocess fired when an input buffer of a scriptprocessornode is ready to be processed.
ScrollToOptions.behavior - Web APIs
when the form is submitted, an event handler is run that puts the entered values into a scrolltooptions dictionary, and then invokes the window.scrollto() method, passing the dictionary as a parameter: form.addeventlistener('submit', (e) => { e.preventdefault(); var scrolloptions = { left: leftinput.value, top: topinput.value, behavior: scrollinput.checked ?
ScrollToOptions.left - Web APIs
when the form is submitted, an event handler is run that puts the entered values into a scrolltooptions dictionary, and then invokes the window.scrollto() method, passing the dictionary as a parameter: form.addeventlistener('submit', (e) => { e.preventdefault(); var scrolloptions = { left: leftinput.value, top: topinput.value, behavior: scrollinput.checked ?
ScrollToOptions.top - Web APIs
when the form is submitted, an event handler is run that puts the entered values into a scrolltooptions dictionary, and then invokes the window.scrollto() method, passing the dictionary as a parameter: form.addeventlistener('submit', (e) => { e.preventdefault(); var scrolloptions = { left: leftinput.value, top: topinput.value, behavior: scrollinput.checked ?
ScrollToOptions - Web APIs
when the form is submitted, an event handler is run that puts the entered values into a scrolltooptions dictionary, and then invokes the window.scrollto() method, passing the dictionary as a parameter: form.addeventlistener('submit', (e) => { e.preventdefault(); var scrolloptions = { left: leftinput.value, top: topinput.value, behavior: scrollinput.checked ?
SecurityPolicyViolationEvent.blockedURI - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.blockeduri); }); specifications specification status comment content security policy level 3the definition of 'blockeduri' in that specification.
SecurityPolicyViolationEvent.columnNumber - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.columnnumber); }); specifications specification status comment content security policy level 3the definition of 'columnnumber' in that specification.
SecurityPolicyViolationEvent.disposition - Web APIs
possible values are "enforce" or "report" example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.disposition); }); specifications specification status comment content security policy level 3the definition of 'disposition' in that specification.
SecurityPolicyViolationEvent.documentURI - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.documenturi); }); specifications specification status comment content security policy level 3the definition of 'documenturi' in that specification.
SecurityPolicyViolationEvent.effectiveDirective - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.effectivedirective); }); specifications specification status comment content security policy level 3the definition of 'effectivedirective' in that specification.
SecurityPolicyViolationEvent.lineNumber - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.linenumber); }); specifications specification status comment content security policy level 3the definition of 'linenumber' in that specification.
SecurityPolicyViolationEvent.originalPolicy - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.originalpolicy); }); specifications specification status comment content security policy level 3the definition of 'originalpolicy' in that specification.
SecurityPolicyViolationEvent.referrer - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.referrer); }); specifications specification status comment content security policy level 3the definition of 'referrer' in that specification.
SecurityPolicyViolationEvent.sample - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.sample); }); specifications specification status comment content security policy level 3the definition of 'sample' in that specification.
SecurityPolicyViolationEvent.sourceFile - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.sourcefile); }); specifications specification status comment content security policy level 3the definition of 'sourcefile' in that specification.
SecurityPolicyViolationEvent.statusCode - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.statuscode); }); specifications specification status comment content security policy level 3the definition of 'statuscode' in that specification.
SecurityPolicyViolationEvent.violatedDirective - Web APIs
example document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.violateddirective); }); specifications specification status comment content security policy level 3the definition of 'violateddirective' in that specification.
SecurityPolicyViolationEvent - Web APIs
examples document.addeventlistener("securitypolicyviolation", (e) => { console.log(e.blockeduri); console.log(e.violateddirective); console.log(e.originalpolicy); }); specifications specification status comment content security policy level 2the definition of 'securitypolicyviolationevent' in that specification.
Selection.addRange() - Web APIs
html <p>i <strong>insist</strong> that you <strong>try</strong> selecting the <strong>strong words</strong>.</p> <button>select strong words</button> javascript let button = document.queryselector('button'); button.addeventlistener('click', function () { let selection = window.getselection(); let strongs = document.getelementsbytagname('strong'); if (selection.rangecount > 0) { selection.removeallranges(); } for (let i = 0; i < strongs.length; i++) { let range = document.createrange(); range.selectnode(strongs[i]); selection.addrange(range); } }); result specifications specificati...
Selection.deleteFromDocument() - Web APIs
once you do, you can remove the selected content by clicking the button below.</p> <button>delete selected text</button> javascript let button = document.queryselector('button'); button.addeventlistener('click', deleteselection); function deleteselection() { let selection = window.getselection(); selection.deletefromdocument(); } result specifications specification status comment selection apithe definition of 'selection.deletefromdocument()' in that specification.
Selection.modify() - Web APIs
WebAPISelectionmodify
lue="lineboundary">line boundary</option> <option value="sentenceboundary">sentence boundary</option> <option value="paragraphboundary">paragraph boundary</option> <option value="documentboundary">document boundary</option> </select> <br><br> <button>extend selection</button> javascript let select = document.queryselector('select'); let button = document.queryselector('button'); button.addeventlistener('click', modify); function modify() { let selection = window.getselection(); selection.modify('extend', 'forward', select.value); } result specifications this method is not part of any specification.
Selection.selectAllChildren() - Web APIs
example html <main> <button>select footer</button> <p>welcome to my website.</p> <p>i hope you enjoy your visit.</p> </main> <footer> <address>webmaster@example.com</address> <p>© 2019</p> </footer> javascript const button = document.queryselector('button'); const footer = document.queryselector('footer'); button.addeventlistener('click', (e) => { window.getselection().selectallchildren(footer); }); result specifications specification status comment selection apithe definition of 'selection.selectallchildren()' in that specification.
Sensor.onactivate - Web APIs
WebAPISensoronactivate
syntax sensorinstance.onactivate = function sensorinstance.addeventlistener('activate', function() { ...
Sensor.onerror - Web APIs
WebAPISensoronerror
syntax sensorinstance.onerror = function sensorinstance.addeventlistener('error', function() { ...
Sensor.onreading - Web APIs
WebAPISensoronreading
syntax sensorinstance.onreading = function sensorinstance.addeventlistener('reading', function() { ...
ServiceWorker.state - Web APIs
document.queryselector('#kind').textcontent = 'installing'; } else if (registration.waiting) { serviceworker = registration.waiting; document.queryselector('#kind').textcontent = 'waiting'; } else if (registration.active) { serviceworker = registration.active; document.queryselector('#kind').textcontent = 'active'; } if (serviceworker) { logstate(serviceworker.state); serviceworker.addeventlistener('statechange', function(e) { logstate(e.target.state); }); } specifications specification status comment service workersthe definition of 'state' in that specification.
ServiceWorker - Web APIs
waiting) { serviceworker = registration.waiting; document.queryselector('#kind').textcontent = 'waiting'; } else if (registration.active) { serviceworker = registration.active; document.queryselector('#kind').textcontent = 'active'; } if (serviceworker) { // logstate(serviceworker.state); serviceworker.addeventlistener('statechange', function (e) { // logstate(e.target.state); }); } }).catch (function (error) { // something went wrong during registration.
ServiceWorkerGlobalScope: activate event - Web APIs
globalscope.addeventlistener('activate', function(event) { var cachewhitelist = ['v2']; event.waituntil( caches.foreach(function(cache, cachename) { if (cachewhitelist.indexof(cachename) == -1) { return caches.delete(cachename); } }) ); }); you can also set up the event handler using the serviceworkerglobalscope.onactivate property: globalscope.onactivate = function(event) { ...
ServiceWorkerGlobalScope: contentdelete event - Web APIs
self.addeventlistener('contentdelete', event => { event.waituntil( caches.open('cache-name').then(cache => { return promise.all([ cache.delete(`/icon/${event.id}`), cache.delete(`/content/${event.id}`) ]) }) ); }); you can also set up the event handler using the serviceworkerglobalscope.ondelete property: self.oncontentdelete = (event) => { ...
ServiceWorkerGlobalScope: install event - Web APIs
bubbles no cancelable no interface extendableevent event handler property serviceworkerglobalscope.oninstall examples the following snippet shows how an install event handler can be used to populate a cache with a number of responses, which the service worker can then use to serve assets offline: this.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.add( '/sw-test/', '/sw-test/index.html', '/sw-test/style.css', '/sw-test/app.js', '/sw-test/image-list.js', '/sw-test/star-wars-logo.jpg', '/sw-test/gallery/', '/sw-test/gallery/bountyhunters.jpg', '/sw-test/galle...
ServiceWorkerGlobalScope: message event - Web APIs
// in the page being controlled if (navigator.serviceworker) { navigator.serviceworker.register('service-worker.js'); navigator.serviceworker.addeventlistener('message', event => { // event is a messageevent object console.log(`the service worker sent me a message: ${event.data}`); }); navigator.serviceworker.ready.then( registration => { registration.active.postmessage("hi service worker"); }); } the service worker can receive the message by listening to the message event: // in the service worker addeventlistener('message', even...
ServiceWorkerGlobalScope: notificationclick event - Web APIs
bubbles no cancelable no interface notificationevent event handler onnotificationclick examples you can use the notificationclick event in an addeventlistener method: self.addeventlistener('notificationclick', function(event) { console.log('on notification click: ', event.notification.tag); event.notification.close(); // this looks to see if the current is already open and // focuses if it is event.waituntil(clients.matchall({ type: "window" }).then(function(clientlist) { for (var i = 0; i < clientlist.length; i++) { var client = clientlist[i]; if (client.url == '/' &...
ServiceWorkerGlobalScope.onactivate - Web APIs
then.addeventlistener('activate', function(event) { var cachewhitelist = ['v2']; event.waituntil( caches.foreach(function(cache, cachename) { if (cachewhitelist.indexof(cachename) == -1) { return caches.delete(cachename); } }) ); }); specifications specification status comment service workersthe definition of 'event handlers' in that specification.
ServiceWorkerGlobalScope.oncontentdelete - Web APIs
self.addeventlistener('contentdelete', event => { event.waituntil( caches.open('cache-name').then(cache => { return promise.all([ cache.delete(`/icon/${event.id}`), cache.delete(`/content/${event.id}`) ]) }) ); }); specifications specification status comment unknownthe definition of 'contentdelete' in that specification.
ServiceWorkerGlobalScope.onfetch - Web APIs
self.addeventlistener('fetch', function(event) { console.log('handling fetch event for', event.request.url); event.respondwith( caches.match(event.request).then(function(response) { if (response) { console.log('found response in cache:', response); return response; } console.log('no response found in cache.
ServiceWorkerGlobalScope.oninstall - Web APIs
}; examples the following snippet shows how an install event handler can be used to populate a cache with a number of responses, which the service worker can then use to serve assets offline: this.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.add( '/sw-test/', '/sw-test/index.html', '/sw-test/style.css', '/sw-test/app.js', '/sw-test/image-list.js', '/sw-test/star-wars-logo.jpg', '/sw-test/gallery/', '/sw-test/gallery/bountyhunters.jpg', '/sw-test/galle...
ServiceWorkerGlobalScope.onmessage - Web APIs
}; example self.addeventlistener('message', function(messageevent) { console.log('handling message event:', messageevent); }) specifications specification status comment service workersthe definition of 'event handlers' in that specification.
onnotificationclose - Web APIs
}; serviceworkerglobalscope.addeventlistener('notificationclose', function(notificationevent) { ...
ServiceWorkerGlobalScope.onsync - Web APIs
} self.addeventlistener('sync', function(syncevent) { ...
ServiceWorkerGlobalScope: push event - Web APIs
self.addeventlistener("push", event => { let message = event.data.json(); switch(message.type) { case "init": doinit(); break; case "shutdown": doshutdown(); break; } }, false); specifications specification status comment push apithe definition of 'push' in that specification.
ServiceWorkerGlobalScope: pushsubscriptionchange event - Web APIs
self.addeventlistener("pushsubscriptionchange", event => { event.waituntil(swregistration.pushmanager.subscribe(event.oldsubscription.options) .then(subscription => { return fetch("register", { method: "post", headers: { "content-type": "application/json" }, body: json.stringify({ endpoint: subscription.endpoint }) }); }) ); }, false);...
ServiceWorkerGlobalScope.skipWaiting() - Web APIs
self.addeventlistener('install', function(event) { // the promise that skipwaiting() returns can be safely ignored.
ServiceWorkerGlobalScope - Web APIs
self.addeventlistener('fetch', function(event) { console.log('handling fetch event for', event.request.url); event.respondwith( caches.match(event.request).then(function(response) { if (response) { console.log('found response in cache:', response); return response; } console.log('no response found in cache.
ServiceWorkerRegistration - Web APIs
if ('serviceworker' in navigator) { navigator.serviceworker.register('/sw.js') .then(function(registration) { registration.addeventlistener('updatefound', function() { // if updatefound is fired, it means that there's // a new service worker being installed.
SharedWorkerGlobalScope: connect event - Web APIs
self.onconnect = function(e) { var port = e.ports[0]; port.onmessage = function(e) { var workerresult = 'result: ' + (e.data[0] * e.data[1]); port.postmessage(workerresult); } port.start(); } for a complete running example, see our basic shared worker example (run shared worker.) addeventlistener equivalent you could also set up an event handler using the addeventlistener() method: self.addeventlistener('connect', function(e) { var port = e.ports[0]; port.onmessage = function(e) { var workerresult = 'result: ' + (e.data[0] * e.data[1]); port.postmessage(workerresult); } }); specifications specification status html living standardthe definition ...
SharedWorkerGlobalScope - Web APIs
events listen to this event using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
SourceBuffer.abort() - Web APIs
for example, consider this code: sourcebuffer.addeventlistener('updateend', function (_) { ...
SourceBuffer - Web APIs
= 'frag_bunny.mp4'; // need to be specific for blink regarding codecs // ./mp4info frag_bunny.mp4 | grep codec var mimecodec = 'video/mp4; codecs="avc1.42e01e, mp4a.40.2"'; if ('mediasource' in window && mediasource.istypesupported(mimecodec)) { var mediasource = new mediasource(); //console.log(mediasource.readystate); // closed video.src = url.createobjecturl(mediasource); mediasource.addeventlistener('sourceopen', sourceopen); } else { console.error('unsupported mime type or codec: ', mimecodec); } function sourceopen (_) { //console.log(this.readystate); // open var mediasource = this; var sourcebuffer = mediasource.addsourcebuffer(mimecodec); fetchab(asseturl, function (buf) { sourcebuffer.addeventlistener('updateend', function (_) { mediasource.endofstream(); vid...
SpeechRecognition: audioend event - Web APIs
bubbles no cancelable no interface event event handler onaudioend examples you can use the audioend event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('audioend', function() { console.log('audio capturing ended'); }); or use the onaudioend event handler property: recognition.onaudioend = function() { console.log('audio capturing ended'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in that specification.
SpeechRecognition: audiostart event - Web APIs
bubbles no cancelable no interface event event handler onaudiostart examples you can use the audiostart event in an onaudiostart method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('audiostart', function() { console.log('audio capturing started'); }); or use the onaudiostart event handler property: recognition.onaudiostart = function() { console.log('audio capturing started'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in that specification.
SpeechRecognition: end event - Web APIs
bubbles no cancelable no interface event event handler property onend examples you can use the end event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('end', function() { console.log('speech recognition service disconnected'); }); or use the onend event handler property: recognition.onend = function() { console.log('speech recognition service disconnected'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in that specification.
SpeechRecognition: error event - Web APIs
bubbles no cancelable no interface speechrecognitionerrorevent event handler property onerror examples you can use the error event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('error', function(event) { console.log('speech recognition error detected: ' + event.error'); }); or use the onerror event handler property: recognition.onerror = function(event) { console.log('speech recognition error detected: ' + event.error'); } specifications specification status comment web speech apithe definition of 'speec...
SpeechRecognition: nomatch event - Web APIs
bubbles no cancelable no interface speechrecognitionevent event handler property onnomatch examples you can use the nomatch event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('nomatch', function() { console.log('speech not recognized'); }); or use the onnomatch event handler property: recognition.onnomatch = function() { console.log('speech not recognized'); } specifications specification status comment web speech apithe de...
SpeechRecognition: result event - Web APIs
you can use the result event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('result', function(event) { var color = event.results[0][0].transcript; diagnostic.textcontent = 'result received: ' + color + '.'; bg.style.backgroundcolor = color; }); or use the onresult event handler property: recognition.onresult = function(event) { var color = event.
SpeechRecognition: soundend event - Web APIs
bubbles no cancelable no interface event event handler property onsoundend examples you can use the soundend event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('soundend', function(event) { console.log('sound has stopped being received'); }); or use the onsoundend event handler property: recognition.onsoundend = function(event) { console.log('sound has stopped being received'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in th...
SpeechRecognition: soundstart event - Web APIs
bubbles no cancelable no interface event event handler property onsoundstart examples you can use the soundstart event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('soundstart', function() { console.log('some sound is being received'); }); or use the onsoundstart event handler property: recognition.onsoundstart = function() { console.log('some sound is being received'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in that specification.
SpeechRecognition: speechend event - Web APIs
bubbles no cancelable no interface event event handler property onspeechend examples you can use the speechend event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('speechend', function() { console.log('speech has stopped being detected'); }); or use the onspeechend event handler property: recognition.onspeechend = function() { console.log('speech has stopped being detected'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in...
SpeechRecognition: speechstart event - Web APIs
bubbles no cancelable no interface event event handler property onspeechstart examples you can use the speechstart event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('speechstart', function() { console.log('speech has been detected'); }); or use the onspeechstart event handler property: recognition.onspeechstart = function() { console.log('speech has been detected'); } specifications specification status comment web speech apithe definition of 'speech recognition events' in tha...
SpeechRecognition: start event - Web APIs
bubbles no cancelable no interface event event handler property onstart examples you can use the start event in an addeventlistener method: var recognition = new webkitspeechrecognition() || new speechrecognition(); recognition.addeventlistener('start', function() { console.log('speech recognition service has started'); }); or use the onstart event handler property: recognition.onstart = function() { console.log('speech recognition service has started'); } specifications specification status comment ...
SpeechRecognition - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
SpeechSynthesis: voiceschanged event - Web APIs
you can use the voiceschanged event in an addeventlistener method: var synth = window.speechsynthesis; synth.addeventlistener('voiceschanged', function() { var voices = synth.getvoices(); for(i = 0; i < voices.length ; i++) { var option = document.createelement('option'); option.textcontent = voices[i].name + ' (' + voices[i].lang + ')'; option.setattribute('data-lang', voices[i].lang); option.setattribute('data-name', voices[i].nam...
SpeechSynthesis - Web APIs
events listen to this event using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
SpeechSynthesisUtterance: boundary event - Web APIs
bubbles no cancelable no interface speechsynthesisevent event handler onboundary examples you can use the boundary event in an addeventlistener method: utterthis.addeventlistener('boundary', function(event) { console.log(event.name + ' boundary reached after ' + event.elapsedtime + ' milliseconds.'); }); or use the onboundary event handler property: utterthis.onboundary = function(event) { console.log(event.name + ' boundary reached after ' + event.elapsedtime + ' milliseconds.'); } specifications specification status comment web speech apithe definition of 'speech synthesis utterance events' ...
SpeechSynthesisUtterance: end event - Web APIs
bubbles no cancelable no interface speechsynthesisevent event handler property onend examples you can use the end event in an addeventlistener method: utterthis.addeventlistener('end', function(event) { console.log('utterance has finished being spoken after ' + event.elapsedtime + ' milliseconds.'); }); or use the onend event handler property: utterthis.onend = function(event) { console.log('utterance has finished being spoken after ' + event.elapsedtime + ' milliseconds.'); } specifications specification status comment web speech apithe definition of 'speech synthesis utterance even...
SpeechSynthesisUtterance: error event - Web APIs
bubbles no cancelable no interface speechsynthesiserrorevent event handler property onerror examples you can use the error event in an addeventlistener method: utterthis.addeventlistener('error', function(event) { console.log('an error has occurred with the speech synthesis: ' + event.error'); }); or use the onerror event handler property: utterthis.onerror = function(event) { console.log('an error has occurred with the speech synthesis: ' + event.error'); } specifications specification status comment web speech apithe definition of 'speech synthes...
SpeechSynthesisUtterance: mark event - Web APIs
bubbles no cancelable no interface speechsynthesisevent event handler property onmark examples you can use the mark event in an addeventlistener method: utterthis.addeventlistener('mark', function(event) { console.log('a mark was reached: ' + event.name); }); or use the onmark event handler property: utterthis.onmark = function(event) { console.log('a mark was reached: ' + event.name); } specifications specification status comment web speech apithe definition of 'speech synthesis utterance events' in that specification.
SpeechSynthesisUtterance: pause event - Web APIs
bubbles no cancelable no interface speechsynthesisevent event handler property onpause examples you can use the pause event in an addeventlistener method: utterthis.addeventlistener('pause', function(event) { console.log('speech paused after ' + event.elapsedtime + ' milliseconds.'); }); or use the onpause event handler property: utterthis.onpause = function(event) { console.log('speech paused after ' + event.elapsedtime + ' milliseconds.'); } specifications specification status comment web speech apithe definition of 'speech synthesis utterance events' in that specification.
SpeechSynthesisUtterance: resume event - Web APIs
bubbles no cancelable no interface speechsynthesisevent event handler property onresume examples you can use the resume event in an addeventlistener method: utterthis.addeventlistener('resume', function(event) { console.log('speech resumed after ' + event.elapsedtime + ' milliseconds.'); }); or use the onresume event handler property: utterthis.onresume = function(event) { console.log('speech resumed after ' + event.elapsedtime + ' milliseconds.'); } specifications specification status comment web speech apithe definition of 'speech synthesis utterance events' in that specification.
SpeechSynthesisUtterance: start event - Web APIs
bubbles no cancelable no interface speechsynthesisevent event handler property onstart examples you can use the start event in an addeventlistener method: utterthis.addeventlistener('start', function(event) { console.log('we have started uttering this speech: ' + event.utterance.text); }); or use the onstart event handler property: utterthis.onstart = function(event) { console.log('we have started uttering this speech: ' + event.utterance.text); } specifications specification status comment web speech apithe definition of 'speech synthesis utterance events' in that specification.
SpeechSynthesisUtterance - Web APIs
events listen to these events using addeventlistener() or by assigning an event listener to the oneventname property of this interface.
Using the Storage Access API - Web APIs
}); note that access requests are automatically denied unless the embedded content is currently processing a user gesture such as a tap or click — so this code needs to be run inside some kind of user gesture-based event handler, for example: btn.addeventlistener('click', () => { // run code here }); ...
Using readable streams - Web APIs
const stream = new readablestream({ start(controller) { interval = setinterval(() => { let string = randomchars(); // add the string to the stream controller.enqueue(string); // show it on the screen let listitem = document.createelement('li'); listitem.textcontent = string; list1.appendchild(listitem); }, 1000); button.addeventlistener('click', function() { clearinterval(interval); readstream(); controller.close(); }) }, pull(controller) { // we don't really need a pull in this example }, cancel() { // this is called if the reader cancels, // so we should stop generating strings clearinterval(interval); } }); in the readstream() function itself, we lock a reader to the stream usi...
SubmitEvent.submitter - Web APIs
let form = document.queryselector("form"); form.addeventlistener("submit", (event) => { let submitter = event.submitter; let handler = submitter.id; if (handler) { processorder(form, handler); } else { showalertmessage("an unknown or unaccepted payment type was selected.
SubmitEvent - Web APIs
let form = document.queryselector("form"); form.addeventlistener("submit", (event) => { let submitter = event.submitter; let handler = submitter.id; if (handler) { processorder(form, handler); } else { showalertmessage("an unknown or unaccepted payment type was selected.
TextTrack.mode - Web APIs
WebAPITextTrackmode
window.addeventlistener("load", event => { let trackelem = document.queryselector("track"); let track = trackelem.track; track.mode = "showing"; for (let index=0; index < track.cues.length; index++) { let cue = track.cues[index]; cue.pauseonexit = true; }; }); specifications specification status comment html living standardthe definition of 'mode' in that specification.
TextTrackList: addtrack event - Web APIs
bubbles no cancelable no interface trackevent event handler property onaddtrack examples using addeventlistener(): const mediaelement = document.queryselector('video, audio'); mediaelement.texttracks.addeventlistener('addtrack', (event) => { console.log(`text track: ${event.track.label} added`); }); using the onaddtrack event handler property: const mediaelement = document.queryselector('video, audio'); mediaelement.texttracks.onaddtrack = (event) => { console.log(`text track: ${event.track.label} added`); }; specifications specification status html living standardthe definition of 'addtrack' in that specification.
TextTrackList: change event - Web APIs
bubbles no cancelable no interface event event handler property onchange examples using addeventlistener(): const mediaelement = document.queryselectorall('video, audio')[0]; mediaelement.texttracks.addeventlistener('change', (event) => { console.log(`'${event.type}' event fired`); }); using the onchange event handler property: const mediaelement = document.queryselector('video, audio'); mediaelement.texttracks.onchange = (event) => { console.log(`'${event.type}' event fired`); }; specifications specification status html living standardthe definition of 'change' in that specification.
TextTrackList.onaddtrack - Web APIs
note: you can also add a handler for the addtrack event using addeventlistener().
TextTrackList.onchange - Web APIs
note: you can also add a handler for the change event using addeventlistener().
TextTrackList.onremovetrack - Web APIs
note: you can also add a handler for the removetrack event using addeventlistener().
TextTrackList: removeTrack event - Web APIs
bubbles no cancelable no interface trackevent event handler property onremovetrack examples using addeventlistener(): const mediaelement = document.queryselector('video, audio'); mediaelement.texttracks.addeventlistener('removetrack', (event) => { console.log(`text track: ${event.track.label} removed`); }); using the onremovetrack event handler property: const mediaelement = document.queryselector('video, audio'); mediaelement.texttracks.onremovetrack = (event) => { console.log(`text track: ${event.track.label} removed`); }; specifications specification status html living standardthe definition of 'removetrack' in that specification.
Touch.clientX - Web APIs
WebAPITouchclientX
// register touchstart and touchend listeners for element 'source' var src = document.getelementbyid("source"); var clientx, clienty; src.addeventlistener('touchstart', function(e) { // cache the client x/y coordinates clientx = e.touches[0].clientx; clienty = e.touches[0].clienty; }, false); src.addeventlistener('touchend', function(e) { var deltax, deltay; // compute the change in x and y coordinates.
Touch.clientY - Web APIs
WebAPITouchclientY
// register touchstart and touchend listeners for element 'source' var src = document.getelementbyid("source"); var clientx, clienty; src.addeventlistener('touchstart', function(e) { // cache the client x/y coordinates clientx = e.touches[0].clientx; clienty = e.touches[0].clienty; }, false); src.addeventlistener('touchend', function(e) { var deltax, deltay; // compute the change in x and y coordinates.
Touch.force - Web APIs
WebAPITouchforce
someelement.addeventlistener('touchstart', function(e) { // iterate through the list of touch points and log each touch // point's force.
Touch.identifier - Web APIs
WebAPITouchidentifier
example someelement.addeventlistener('touchmove', function(e) { // iterate through the list of touch points that changed // since the last event and print each touch point's identifier.
Touch.pageX - Web APIs
WebAPITouchpageX
// register a touchmove listeners for the 'source' element var src = document.getelementbyid("source"); src.addeventlistener('touchmove', function(e) { // iterate through the touch points that have moved and log each // of the pagex/y coordinates.
Touch.pageY - Web APIs
WebAPITouchpageY
// register a touchmove listeners for the 'source' element var src = document.getelementbyid("source"); src.addeventlistener('touchmove', function(e) { // iterate through the touch points that have moved and log each // of the pagex/y coordinates.
Touch.radiusX - Web APIs
WebAPITouchradiusX
</div> var src = document.getelementbyid("src"); src.addeventlistener('touchstart', rotate); src.addeventlistener('touchmove', rotate); src.addeventlistener('touchend', rotate); function rotate (e) { var touch = e.changedtouches.item(0); // turn off default event handling e.preventdefault(); // rotate element 'src'.
Touch.screenX - Web APIs
WebAPITouchscreenX
// register a touchstart listeners for the 'source' element var src = document.getelementbyid("source"); src.addeventlistener('touchstart', function(e) { // iterate through the touch points and log each screenx/y coordinate.
Touch.target - Web APIs
WebAPITouchtarget
// register a touchmove listener for the 'source' element var src = document.getelementbyid("source"); src.addeventlistener('touchstart', function(e) { // iterate through the touch points that were activiated // for this element.
TouchEvent.altKey - Web APIs
WebAPITouchEventaltKey
someelement.addeventlistener('touchstart', function(e) { // log the state of this event's modifier keys console.log("altkey = " + e.altkey); console.log("ctrlkey = " + e.ctrlkey); console.log("metakey = " + e.metakey); console.log("shiftkey = " + e.shiftkey); }, false); specifications specification status comment touch events – level 2 draft non-stable version.
TouchEvent.changedTouches - Web APIs
someelement.addeventlistener('touchmove', function(e) { // iterate through the list of touch points that changed // since the last event and print each touch point's identifier.
TouchEvent.touches - Web APIs
someelement.addeventlistener('touchstart', function(e) { // invoke the appropriate handler depending on the // number of touch points.
TouchEvent - Web APIs
using with addeventlistener() and preventdefault() it's important to note that in many cases, both touch and mouse events get sent (in order to let non-touch-specific code still interact with the user).
TouchList.item() - Web APIs
WebAPITouchListitem
target = document.getelementbyid("target"); target.addeventlistener('touchstart', function(ev) { // if this touchstart event started on element target, // set touch to the first item in the targettouches list; // otherwise set touch to the first item in the touches list var touch; if (ev.targettouches.length >= 1) touch = ev.targettouches.item(0); else touch = ev.touches.item(0); }, false); specifications specification stat...
TouchList.length - Web APIs
WebAPITouchListlength
target = document.getelementbyid("target"); target.addeventlistener('touchstart', function(ev) { // if this touchstart event started on element target, // set touch to the first item in the targettouches list; // otherwise set touch to the first item in the touches list var touch; if (ev.targettouches.length >= 1) touch = ev.targettouches.item(0); else touch = ev.touches.item(0); }, false); specifications specification status comment ...
Touch events - Web APIs
function startup() { var el = document.getelementbyid("canvas"); el.addeventlistener("touchstart", handlestart, false); el.addeventlistener("touchend", handleend, false); el.addeventlistener("touchcancel", handlecancel, false); el.addeventlistener("touchmove", handlemove, false); } document.addeventlistener("domcontentloaded", startup); this simply sets up all the event listeners for our <canvas> element so we can handle the touch events as they occur.
TrackEvent - Web APIs
var videoelem = document.queryselector("video"); videoelem.videotracks.addeventlistener("addtrack", handletrackevent, false); videoelem.videotracks.addeventlistener("removetrack", handletrackevent, false); videoelem.audiotracks.addeventlistener("addtrack", handletrackevent, false); videoelem.audiotracks.addeventlistener("removetrack", handletrackevent, false); videoelem.texttracks.addeventlistener("addtrack", handletrackevent, false); videoelem.texttracks.addeventlistener("removetra...
VTTCue - Web APIs
WebAPIVTTCue
example html <video controls src="https://udn.realityripple.com/samples/c6/f8a3489533.webm"></video> css video { width: 320px; height: 180px; } javascript let video = document.queryselector('video'); video.addeventlistener('loadedmetadata', () => { const track = video.addtexttrack("captions", "简体中文subtitles", "zh_cn"); track.mode = "showing"; const cuecn = new vttcue(0, 2.500, '字幕会在0至2.5秒间显示'); track.addcue(cuecn); const cueen = new vttcue(2.6, 4, 'subtitles will display between 2.6 and 4 seconds'); track.addcue(cueen); }); result chrome: please open in jsfiddle to view...
VideoTrackList: addtrack event - Web APIs
bubbles no cancelable no interface trackevent event handler property onaddtrack examples using addeventlistener(): const videoelement = document.queryselector('video'); videoelement.videotracks.addeventlistener('addtrack', (event) => { console.log(`video track: ${event.track.label} added`); }); using the onaddtrack event handler property: const videoelement = document.queryselector('video'); videoelement.videotracks.onaddtrack = (event) => { console.log(`video track: ${event.track.label} added`); }; specifications specification status html living standardthe definition of 'addtrack' in that specification.
VideoTrackList.onaddtrack - Web APIs
note: you can also add a handler for the addtrack event using addeventlistener().
VideoTrackList.onchange - Web APIs
note: you can also add a handler for the change event using addeventlistener().
VideoTrackList.onremovetrack - Web APIs
note: you can also add a handler for the removetrack event using addeventlistener().
VideoTrackList: removetrack event - Web APIs
bubbles no cancelable no interface trackevent event handler property onremovetrack examples using addeventlistener(): const videoelement = document.queryselector('video'); videoelement.videotracks.addeventlistener('removetrack', (event) => { console.log(`video track: ${event.track.label} removed`); }); using the onremovetrack event handler property: const videoelement = document.queryselector('video'); videoelement.videotracks.onremovetrack = (event) => { console.log(`video track: ${event.track.label} removed`); }; specifications specification status html living standardthe definition of 'removetrack' in that specification.
VisualViewport: resize event - Web APIs
bubbles no cancelable no interface event event handler property onresize examples you can use the resize event in an addeventlistener method: visualviewport.addeventlistener('resize', function() { ...
VisualViewport: scroll event - Web APIs
bubbles no cancelable no interface event event handler property onscroll examples you can use the scroll event in an addeventlistener method: visualviewport.addeventlistener('scroll', function() { ...
Visual Viewport API - Web APIs
bottombar.style.transform = 'translate(' + offsetleft + 'px,' + offsettop + 'px) ' + 'scale(' + 1/viewport.scale + ')' }) } window.visualviewport.addeventlistener('scroll', viewporthandler); window.visualviewport.addeventlistener('resize', viewporthandler); specifications specification status comment visual viewport apithe definition of 'visualviewport' in that specification.
WEBGL_lose_context.loseContext() - Web APIs
syntax gl.getextension('webgl_lose_context').losecontext(); examples with this method, you can simulate the webglcontextlost event: var canvas = document.getelementbyid('canvas'); var gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextlost', function(e) { console.log(e); }, false); gl.getextension('webgl_lose_context').losecontext(); // webglcontextevent event with type "webglcontextlost" is logged.
WEBGL_lose_context.restoreContext() - Web APIs
examples with this method, you can simulate the webglcontextrestored event: var canvas = document.getelementbyid('canvas'); var gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextrestored', function(e) { console.log(e); }, false); gl.getextension('webgl_lose_context').restorecontext(); specifications specification status comment webgl_lose_contextthe definition of 'webgl_lose_context.losecontext' in that specification.
WEBGL_lose_context - Web APIs
examples with this extension, you can simulate the webglcontextlost and webglcontextrestored events: const canvas = document.getelementbyid('canvas'); const gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextlost', (event) => { console.log(event); }); gl.getextension('webgl_lose_context').losecontext(); // webglcontextevent event with type "webglcontextlost" is logged.
WakeLockSentinel.release() - Web APIs
wakelockoffbutton.addeventlistener('click', () => { wakelocksentinel.release(); }) specifications specification status comment screen wake lock apithe definition of 'release()' in that specification.
WakeLockSentinel - Web APIs
// create a reference for the wake lock let wakelock = null; // create an async function to request a wake lock const requestwakelock = async () => { try { wakelock = await navigator.wakelock.request('screen'); // listen for our release event wakelock.addeventlistener('release', () => { // if wake lock is released alter the ui accordingly }); } catch (err) { // if wake lock request fails - usually system related, such as battery } } wakelockonbutton.addeventlistener('click', () => { requestwakelock(); }) wakelockoffbutton.addeventlistener('click', () => { if (wakelock !== null) { wakelock.release() .then(() => { wake...
WebGLContextEvent.statusMessage - Web APIs
var canvas = document.getelementbyid('canvas'); var gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextcreationerror', function(e) { console.log('webgl context creation failed:' + e.statusmessage || 'unknown error'); }, false); specifications specification status comment webgl 1.0the definition of 'webglcontextevent.statusmessage' in that specification.
WebGLContextEvent - Web APIs
examples with the help of the webgl_lose_context extension, you can simulate the webglcontextlost and webglcontextrestored events: var canvas = document.getelementbyid('canvas'); var gl = canvas.getcontext('webgl'); canvas.addeventlistener('webglcontextlost', function(e) { console.log(e); }, false); gl.getextension('webgl_lose_context').losecontext(); // webglcontextevent event with type "webglcontextlost" is logged.
WebGLRenderingContext - Web APIs
<p>compare the two canvases.</p> <canvas>your browser does not seem to support html5 canvas.</canvas> <canvas>your browser does not seem to support html5 canvas.</canvas> body { text-align : center; } canvas { display : inline-block; width : 120px; height : 80px; margin : auto; padding : 0; border : none; background-color : black; } window.addeventlistener("load", function() { "use strict" var firstcanvas = document.getelementsbytagname("canvas")[0], secondcanvas = document.getelementsbytagname("canvas")[1]; firstcanvas.width = firstcanvas.clientwidth; firstcanvas.height = firstcanvas.clientheight; [firstcanvas, secondcanvas].foreach(function(canvas) { var gl = canvas.getcontext("webgl") || canvas.getcontext("experimental-we...
A basic 2D WebGL animation example - Web APIs
let uscalingfactor; let uglobalcolor; let urotationvector; let avertexposition; // animation timing let previoustime = 0.0; let degreespersecond = 90.0; initializing the program is handled through a load event handler called startup(): window.addeventlistener("load", startup, false); function startup() { glcanvas = document.getelementbyid("glcanvas"); gl = glcanvas.getcontext("webgl"); const shaderset = [ { type: gl.vertex_shader, id: "vertex-shader" }, { type: gl.fragment_shader, id: "fragment-shader" } ]; shaderprogram = buildshaderprogram(shaderset); aspectratio = glcanvas.width/glcanvas.heigh...
Basic scissoring - Web APIs
<p>result of of scissoring.</p> <canvas>your browser does not seem to support html5 canvas.</canvas> body { text-align : center; } canvas { display : block; width : 280px; height : 210px; margin : auto; padding : 0; border : none; background-color : black; } window.addeventlistener("load", function setupwebgl (evt) { "use strict" window.removeeventlistener(evt.type, setupwebgl, false); var paragraph = document.queryselector("p"); var canvas = document.queryselector("canvas"); // the following two lines set the size (in css pixels) of // the drawing buffer to be identical to the size of the // canvas html element, as determined by css.
Canvas size and WebGL - Web APIs
<p>compare the two canvases.</p> <canvas>your browser does not seem to support html5 canvas.</canvas> <canvas>your browser does not seem to support html5 canvas.</canvas> body { text-align : center; } canvas { display : inline-block; width : 120px; height : 80px; margin : auto; padding : 0; border : none; background-color : black; } window.addeventlistener("load", function() { "use strict" var firstcanvas = document.getelementsbytagname("canvas")[0], secondcanvas = document.getelementsbytagname("canvas")[1]; firstcanvas.width = firstcanvas.clientwidth; firstcanvas.height = firstcanvas.clientheight; [firstcanvas, secondcanvas].foreach(function(canvas) { var gl = canvas.getcontext("webgl") || canvas.getcontext("experimental-we...
Clearing with colors - Web APIs
window.addeventlistener("load", function setupwebgl (evt) { "use strict" // cleaning after ourselves.
Hello GLSL - Web APIs
t-size : inherit; margin : auto; padding : 0.6em; } <script type="x-shader/x-vertex" id="vertex-shader"> #version 100 void main() { gl_position = vec4(0.0, 0.0, 0.0, 1.0); gl_pointsize = 64.0; } </script> <script type="x-shader/x-fragment" id="fragment-shader"> #version 100 void main() { gl_fragcolor = vec4(0.18, 0.54, 0.34, 1.0); } </script> ;(function(){ "use strict" window.addeventlistener("load", setupwebgl, false); var gl, program; function setupwebgl (evt) { window.removeeventlistener(evt.type, setupwebgl, false); if (!(gl = getrenderingcontext())) return; var source = document.queryselector("#vertex-shader").innerhtml; var vertexshader = gl.createshader(gl.vertex_shader); gl.shadersource(vertexshader,source); gl.compileshader(vertexshader); source = documen...
Raining rectangles - Web APIs
ng>0</strong>.</p> <canvas>your browser does not seem to support html5 canvas.</canvas> body { text-align : center; } canvas { display : block; width : 280px; height : 210px; margin : auto; padding : 0; border : none; background-color : black; } button { display : block; font-size : inherit; margin : auto; padding : 0.6em; } ;(function(){ "use strict" window.addeventlistener("load", setupanimation, false); var gl, timer, rainingrect, scoredisplay, missesdisplay; function setupanimation (evt) { window.removeeventlistener(evt.type, setupanimation, false); if (!(gl = getrenderingcontext())) return; gl.enable(gl.scissor_test); rainingrect = new rectangle(); timer = settimeout(drawanimation, 17); document.queryselector("canvas") .addeventlis...
Textures from code - Web APIs
; } </script> <script type="x-shader/x-fragment" id="fragment-shader"> #version 100 precision mediump float; void main() { vec2 fragmentposition = 2.0*gl_pointcoord - 1.0; float distance = length(fragmentposition); float distancesqrd = distance * distance; gl_fragcolor = vec4( 0.2/distancesqrd, 0.1/distancesqrd, 0.0, 1.0 ); } </script> ;(function(){ "use strict" window.addeventlistener("load", setupwebgl, false); var gl, program; function setupwebgl (evt) { window.removeeventlistener(evt.type, setupwebgl, false); if (!(gl = getrenderingcontext())) return; var source = document.queryselector("#vertex-shader").innerhtml; var vertexshader = gl.createshader(gl.vertex_shader); gl.shadersource(vertexshader,source); gl.compileshader(vertexshader); source = documen...
Animating textures in WebGL - Web APIs
t we'll use to retrieve the video frames: // will set to true when video can be copied to texture var copyvideo = false; function setupvideo(url) { const video = document.createelement('video'); var playing = false; var timeupdate = false; video.autoplay = true; video.muted = true; video.loop = true; // waiting for these 2 events ensures // there is data in the video video.addeventlistener('playing', function() { playing = true; checkready(); }, true); video.addeventlistener('timeupdate', function() { timeupdate = true; checkready(); }, true); video.src = url; video.play(); function checkready() { if (playing && timeupdate) { copyvideo = true; } } return video; } first we create a video element.
Signaling and video calling - Web APIs
function handleuserlistmsg(msg) { var i; var listelem = document.queryselector(".userlistbox"); while (listelem.firstchild) { listelem.removechild(listelem.firstchild); } msg.users.foreach(function(username) { var item = document.createelement("li"); item.appendchild(document.createtextnode(username)); item.addeventlistener("click", invite, false); listelem.appendchild(item); }); } after getting a reference to the <ul> which contains the list of user names into the variable listelem, we empty the list by removing each of its child elements.
A simple RTCDataChannel sample - Web APIs
function startup() { connectbutton = document.getelementbyid('connectbutton'); disconnectbutton = document.getelementbyid('disconnectbutton'); sendbutton = document.getelementbyid('sendbutton'); messageinputbox = document.getelementbyid('message'); receivebox = document.getelementbyid('receivebox'); // set event listeners for user interface widgets connectbutton.addeventlistener('click', connectpeers, false); disconnectbutton.addeventlistener('click', disconnectpeers, false); sendbutton.addeventlistener('click', sendmessage, false); } this is quite straightforward.
WebSocket: close event - Web APIs
examplesocket.addeventlistener('close', (event) => { console.log('the connection has been closed successfully.'); )}; you can perform the same actions using the event handler property, like this: examplesocket.onclose = function (event) { console.log('the connection has been closed successfully.'); }; specifications specification status html living standardthe definition of 'websocket close' in...
WebSocket: error event - Web APIs
bubbles no cancelable no interface event event handler property onerror examples // create websocket connection const socket = new websocket('ws://localhost:8080'); // listen for possible errors socket.addeventlistener('error', function (event) { console.log('websocket error: ', event); }); specifications specification status html living standardthe definition of 'websocket error' in that specification.
WebSocket: message event - Web APIs
const socket = new websocket('ws://localhost:8080'); // listen for messages socket.addeventlistener('message', function (event) { console.log('message from server ', event.data); }); specifications specification status html living standardthe definition of 'websocket message' in that specification.
WebSocket.onerror - Web APIs
WebAPIWebSocketonerror
you can also add an error event handler using addeventlistener().
WebSocket: open event - Web APIs
const socket = new websocket('ws://localhost:8080'); // connection opened socket.addeventlistener('open', (event) => { socket.send('hello server!'); }); specifications specification status html living standardthe definition of 'websocket open' in that specification.
Writing a WebSocket server in C# - Web APIs
textarea> <button>send</button> <div id=output></div> <script> // http://www.websocket.org/echo.html var button = document.queryselector("button"), output = document.queryselector("#output"), textarea = document.queryselector("textarea"), // wsuri = "ws://echo.websocket.org/", wsuri = "ws://127.0.0.1/", websocket = new websocket(wsuri); button.addeventlistener("click", onclickbutton); websocket.onopen = function (e) { writetoscreen("connected"); dosend("websocket rocks"); }; websocket.onclose = function (e) { writetoscreen("disconnected"); }; websocket.onmessage = function (e) { writetoscreen("<span>response: " + e.data + "</span>"); }; websocket.onerror = function (e) { writetoscr...
Starting up and shutting down a WebXR session - Web APIs
in basic form, code to do this final setup might look something like this: async function runsession(session) { let worlddata; session.addeventlistener("end", onsessionend); let canvas = document.queryselector("canvas"); gl = canvas.getcontext("webgl", { xrcompatible: true }); // set up webgl data and such worlddata = loadglprograms(session, "worlddata.xml"); if (!worlddata) { return null; } // finish configuring webgl worlddata.session.updaterenderstate({ baselayer: new xrwebgllayer(worlddata.session, gl) }); /...
Web audio spatialization basics - Web APIs
() => moveboombox(direction, move)); return move; } wiring up our controls wiring up out control buttons is comparatively simple — now we can listen for a mouse event on our controls and run this function, as well as stop it when the mouse is released: // for each of our controls, move the boombox and change the position values movecontrols.foreach(function(el) { let moving; el.addeventlistener('mousedown', function() { let direction = this.dataset.control; if (moving && moving.frameid) { window.cancelanimationframe(moving.frameid); } moving = moveboombox(direction); }, false); window.addeventlistener('mouseup', function() { if (moving && moving.frameid) { window.cancelanimationframe(moving.frameid); } ...
Using the Web Storage API - Web APIs
on the events page (see events.js) the only javascript is as follows: window.addeventlistener('storage', function(e) { document.queryselector('.my-key').textcontent = e.key; document.queryselector('.my-old').textcontent = e.oldvalue; document.queryselector('.my-new').textcontent = e.newvalue; document.queryselector('.my-url').textcontent = e.url; document.queryselector('.my-storage').textcontent = json.stringify(e.storagearea); }); here we add an event listener to the window ob...
Using Web Workers - Web APIs
calling start() is only needed if the message event is wired up via the addeventlistener() method.
Window: DOMContentLoaded event - Web APIs
examples basic usage window.addeventlistener('domcontentloaded', (event) => { console.log('dom fully loaded and parsed'); }); specifications specification status html living standard living standard ...
Window: afterprint event - Web APIs
bubbles no cancelable no interface event event handler property onafterprint examples using addeventlistener(): window.addeventlistener('afterprint', (event) => { console.log('after print'); }); using the onafterprint event handler property: window.onafterprint = (event) => { console.log('after print'); }; specifications specification status html living standard living standard ...
Window: animationcancel event - Web APIs
window.addeventlistener('animationcancel', () => { console.log('animation canceled'); }); the same, but using the onanimationcancel property instead of addeventlistener(): window.onanimationcancel = () => { console.log('animation canceled'); }; see a live example of this event.
Window: animationend event - Web APIs
examples this example listens for the animationend event: window.addeventlistener('animationend', () => { console.log('animation ended'); }); the same, but using the onanimationend event handler property: window.onanimationend = () => { console.log('animation ended'); }; see a live example of this event.
Window: animationiteration event - Web APIs
examples this code uses animationiteration to keep track of the number of iterations an animation has completed: let iterationcount = 0; window.addeventlistener('animationiteration', () => { iterationcount++; console.log(`animation iteration count: ${iterationcount}`); }); the same, but using the onanimationiteration event handler property: let iterationcount = 0; window.onanimationiteration = () => { iterationcount++; console.log(`animation iteration count: ${iterationcount}`); }; see a live example of this event.
Window: animationstart event - Web APIs
examples this listens for the animationstart event and logs a message when it is fired: window.addeventlistener('animationstart', () => { console.log('animation started'); }); the same, but using onanimationstart: window.onanimationstart = () => { console.log('animation started'); }; see a live example of this event.
Window: appinstalled event - Web APIs
bubbles no cancelable no interface event event handler onappinstalled examples you can use the appinstalled event in an addeventlistener method: window.addeventlistener('appinstalled', function() { console.log('thank you for installing our app!'); }); or use the onappinstalled event handler property: window.onappinstalled = function() { console.log('thank you for installing our app!'); }; ...
Window: beforeprint event - Web APIs
bubbles no cancelable no interface event event handler property onbeforeprint examples using addeventlistener(): window.addeventlistener('beforeprint', (event) => { console.log('before print'); }); using the onbeforeprint event handler property: window.onbeforeprint = (event) => { console.log('before print'); }; specifications specification status html living standard living standard ...
Window: beforeunload event - Web APIs
window.addeventlistener('beforeunload', (event) => { // cancel the event as stated by the standard.
Window.clearImmediate() - Web APIs
examples let immediateid = setimmediate(() => { // run some code } document.getelementbyid("button") .addeventlistener(() => { clearimmediate(immediateid); }); specifications specification status comment efficient script yielding the definition of 'setimmediate' in that specification.
Window: clipboardchange event - Web APIs
bubbles no cancelable no interface clipboardevent event handler property none examples javascript window.addeventlistener('clipboardchange', () => { console.log('clipboard contents changed'); }); specifications specification status clipboard api and eventsthe definition of 'clipboardchange event' in that specification.
Window: copy event - Web APIs
WebAPIWindowcopy event
examples window.addeventlistener('copy', (event) => { console.log('copy action initiated') }); specifications specification status clipboard api and events working draft ...
Window: cut event - Web APIs
WebAPIWindowcut event
examples window.addeventlistener('cut', (event) => { console.log('cut action initiated') }); specifications specification status clipboard api and events working draft ...
Window.devicePixelRatio - Web APIs
then the updatepixelratio() function is called once to display the starting value, after which the media query is created using matchmedia() and addeventlistener() is called to set up updatepixelratio() as a handler for the change event.
Window: devicemotion event - Web APIs
} window.addeventlistener("devicemotion", handlemotionevent, true); specifications specification status deviceorientation event specificationthe definition of 'devicemotion event' in that specification.
Window: deviceorientation event - Web APIs
bubbles no cancelable no interface deviceorientationevent event handler property window.ondeviceorientation examples if (window.deviceorientationevent) { window.addeventlistener("deviceorientation", function(event) { // alpha: rotation around z-axis var rotatedegrees = event.alpha; // gamma: left to right var lefttoright = event.gamma; // beta: front back motion var fronttoback = event.beta; handleorientationevent(fronttoback, lefttoright, rotatedegrees); }, true); } var handleorientationevent = function(front...
Window: error event - Web APIs
plate-areas: "control log"; } .controls { grid-area: control; display: flex; align-items: center; justify-content: center; } .event-log { grid-area: log; } .event-log-contents { resize: none; } label, button { display: block; } button { height: 2rem; margin: .5rem; } img { width: 0; height: 0; } js const log = document.queryselector('.event-log-contents'); window.addeventlistener('error', (event) => { log.textcontent = log.textcontent + `${event.type}: ${event.message}\n`; console.log(event) }); const scripterror = document.queryselector('#script-error'); scripterror.addeventlistener('click', () => { const badcode = 'const s;'; eval(badcode); }); result specifications specification status ui events working draft ...
Window: gamepadconnected event - Web APIs
bubbles no cancelable no interface gamepadevent event handler property ongamepadconnected examples window.addeventlistener('gamepadconnected', event => { // all buttons and axes values can be accessed through event.gamepad; }); specifications specification status gamepad working draft ...
Window: gamepaddisconnected event - Web APIs
bubbles no cancelable no interface gamepadevent event handler property ongamepaddisconnected examples window.addeventlistener('gamepaddisconnected', event => { console.log('lost connection with the gamepad.'); }); specifications specification status gamepad working draft ...
Window: hashchange event - Web APIs
bubbles yes cancelable no interface hashchangeevent event handler onhashchange examples you can use the hashchange event in an addeventlistener method: window.addeventlistener('hashchange', function() { console.log('the hash has changed!') }, false); or use the onhashchange event handler property: function locationhashchanged() { if (location.hash === '#cool-feature') { console.log("you're visiting a cool feature!"); } } window.onhashchange = locationhashchanged; specifications specification status comment html living standardthe definition of 'hashchange' in t...
Window: languagechange event - Web APIs
bubbles no cancelable no interface event event handler onlanguagechange examples you can use the languagechange event in an addeventlistener method: window.addeventlistener('languagechange', function() { console.log('languagechange event detected!'); }); or use the onlanguagechange event handler property: window.onlanguagechange = function(event) { console.log('languagechange event detected!'); }; specification specification status html living standardthe definition of 'languagechange' in that specification.
window.location - Web APIs
WebAPIWindowlocation
rolly + (_nodey - _scrolly) * _itframe / nframes); document.documentelement.scrollleft = math.round(_scrollx + (_nodex - _scrollx) * _itframe / nframes); if (_usehash && _itframe === nframes) { location.hash = _bookmark; } _itframe++; } function _chkowner () { if (_isbot) { _isbot = false; return; } if (_scrollid > -1) { clearinterval(_scrollid); _scrollid = -1; } } if (window.addeventlistener) { window.addeventlistener("scroll", _chkowner, false); } else if (window.attachevent) { window.attachevent("onscroll", _chkowner); } return function (sbookmark, busehash) { var onode = document.queryselector(sbookmark); _scrolly = document.documentelement.scrolltop; _scrollx = document.documentelement.scrollleft; _bookmark = sbookmark; _usehash = busehash === true; _nodex = on...
Window: message event - Web APIs
ble no interface messageevent event handler property onmessage examples suppose a script sends a message to a different browsing context, such as another <iframe>, using code like this: const targetframe = window.top.frames[1]; const targetorigin = 'https://example.org'; const windowmessagebutton = document.queryselector('#window-message'); windowmessagebutton.addeventlistener('click', () => { targetframe.postmessage('hello there', targetorigin); }); the receiver can listen for the message using addeventlistener() with code like this: window.addeventlistener('message', (event) => { console.log(`received message: ${event.data}`); }); alternatively the listener could use the onmessage event handler property: window.onmessage = (event) => { console.log(`re...
Window: messageerror event - Web APIs
bubbles no cancelable no interface messageevent event handler property onmessageerror examples listen for messageerror using addeventlistener(): window.addeventlistener('messageerror', (event) => { console.error(event); }); the same, but using the onmessageerror event handler property: window.onmessageerror = (event) => { console.error(event); }; specifications specification status html living standard living standard ...
Window: offline event - Web APIs
bubbles no cancelable no interface event event handler property onoffline examples // addeventlistener version window.addeventlistener('offline', (event) => { console.log("the network connection has been lost."); }); // onoffline version window.onoffline = (event) => { console.log("the network connection has been lost."); }; specifications specification status html living standardthe definition of 'offline event' in that specification.
window.ondeviceorientation - Web APIs
}; window.addeventlistener('deviceorientation', function(event) { ...
Window.ondeviceorientationabsolute - Web APIs
}; window.addeventlistener('deviceorientationabsolute', function(event) { ...
Window: online event - Web APIs
bubbles no cancelable no interface event event handler property ononline examples // addeventlistener version window.addeventlistener('online', (event) => { console.log("you are now connected to the network."); }); // ononline version window.ononline = (event) => { console.log("you are now connected to the network."); }; specifications specification status html living standardthe definition of 'online event' in that specification.
Window: orientationchange event - Web APIs
bubbles no cancelable no interface event event handler onorientationchange example you can use the orientationchange event in an addeventlistener method: window.addeventlistener("orientationchange", function(event) { console.log("the orientation of the device is now " + event.target.screen.orientation.angle); }); or use the onorientationchange event handler property: window.onorientationchange = function(event) { console.log("the orientation of the device is now " + event.target.screen.orientation.angle); }; specifications specification status compatibility standardthe definition of 'orientationchange' in that specification.
Window: pagehide event - Web APIs
window.addeventlistener("pagehide", event => { if (event.persisted) { /* the page isn't being discarded, so it can be reused later */ } }, false); this can also be written using the onpagehide event handler property on the window: window.onpagehide = event => { if (event.persisted) { /* the page isn't being discarded, so it can be reused later */ } } specifications specification status ...
Window: pageshow event - Web APIs
"persisted" : "not persisted"; console.log('event:', event.type, '-', ispersisted); break; default: console.log('event:', event.type); break; } }; events.foreach(eventname => window.addeventlistener(eventname, eventlogger) ); html <p>open the console and watch the output as you navigate to and from this page.
Window: paste event - Web APIs
examples window.addeventlistener('paste', (event) => { console.log('paste action initiated') }); specifications specification status clipboard api and events working draft ...
Window: popstate event - Web APIs
examples a page at http://example.com/example.html running the following code will generate logs as indicated: window.addeventlistener('popstate', (event) => { console.log("location: " + document.location + ", state: " + json.stringify(event.state)); }); history.pushstate({page: 1}, "title 1", "?page=1"); history.pushstate({page: 2}, "title 2", "?page=2"); history.replacestate({page: 3}, "title 3", "?page=3"); history.back(); // logs "location: http://example.com/example.html?page=1, state: {"page":1}" history.back(); // logs ...
Window: rejectionhandled event - Web APIs
bubbles no cancelable no interface promiserejectionevent event handler property onrejectionhandled example you can use the rejectionhandled event to log promises that get rejected to the console, along with the reasons why they were rejected: window.addeventlistener("rejectionhandled", event => { console.log("promise rejected; reason: " + event.reason); }, false); specifications specification status comment html living standardthe definition of 'rejectionhandled' in that specification.
Window.sessionStorage - Web APIs
// get the text field that we're going to track let field = document.getelementbyid("field"); // see if we have an autosave value // (this will only happen if the page is accidentally refreshed) if (sessionstorage.getitem("autosave")) { // restore the contents of the text field field.value = sessionstorage.getitem("autosave"); } // listen for changes in the text field field.addeventlistener("change", function() { // and save the results into the session storage object sessionstorage.setitem("autosave", field.value); }); note: please refer to the using the web storage api article for a full example.
Window: storage event - Web APIs
bubbles no cancelable no interface storageevent event handler property onstorage examples log the samplelist item to the console when the storage event fires: window.addeventlistener('storage', () => { // when local storage changes, dump the list to // the console.
Window: transitioncancel event - Web APIs
examples this code adds a listener to the transitioncancel event: window.addeventlistener('transitioncancel', () => { console.log('transition canceled'); }); the same, but using the ontransitioncancel property instead of addeventlistener(): window.ontransitioncancel = () => { console.log('transition canceled'); }; see a live example of this event.
Window: transitionend event - Web APIs
examples this code adds a listener to the transitionend event: window.addeventlistener('transitionend', () => { console.log('transition ended'); }); the same, but using the ontransitionend property instead of addeventlistener(): window.ontransitionend = () => { console.log('transition ended'); }; see a live example of this event.
Window: transitionrun event - Web APIs
examples this code adds a listener to the transitionrun event: window.addeventlistener('transitionrun', () => { console.log('transition is running but hasn't necessarily started transitioning yet'); }); the same, but using the ontransitionrun property instead of addeventlistener(): window.ontransitionrun = () => { console.log('transition started running'); }; see a live example of this event.
Window: transitionstart event - Web APIs
examples this code adds a listener to the transitionstart event: window.addeventlistener('transitionstart', () => { console.log('started transitioning'); }); the same, but using the ontransitionstart property instead of addeventlistener(): window.ontransitionrun = () => { console.log('started transitioning'); }; see a live example of this event.
WindowClient.focus() - Web APIs
example self.addeventlistener('notificationclick', function(event) { console.log('on notification click: ', event.notification.tag); event.notification.close(); // this looks to see if the current is already open and // focuses if it is event.waituntil(clients.matchall({ type: "window" }).then(function(clientlist) { for (var i = 0; i < clientlist.length; i++) { var client = clientlist[i]; if (client...
WindowClient.focused - Web APIs
example self.addeventlistener('notificationclick', function(event) { console.log('on notification click: ', event.notification.tag); event.notification.close(); // this looks to see if the current is already open and // focuses if it is event.waituntil(clients.matchall({ type: "window" }).then(function(clientlist) { for (var i = 0; i < clientlist.length; i++) { var client = clientlist[i]; if (client.url == '/' && 'focus' in client) { if(!client.focused) return client.focus(); } } } if (clients.openwindow) return clients.openwindow('/')...
WindowClient - Web APIs
example self.addeventlistener('notificationclick', function(event) { console.log('on notification click: ', event.notification.tag); event.notification.close(); // this looks to see if the current is already open and // focuses if it is event.waituntil(clients.matchall({ type: "window" }).then(function(clientlist) { for (var i = 0; i < clientlist.length; i++) { var client = clientlist[i]; if (...
WindowEventHandlers.onafterprint - Web APIs
syntax window.addeventlistener("afterprint", function(event) { ...
WindowEventHandlers.onbeforeprint - Web APIs
syntax window.addeventlistener("beforeprint", function(event) { ...
WindowEventHandlers.onmessage - Web APIs
syntax window.addeventlistener('message', function(event) { ...
WindowEventHandlers.onrejectionhandled - Web APIs
syntax window.addeventlistener("rejectionhandled", function(event) { ...
WindowOrWorkerGlobalScope.caches - Web APIs
this.addeventlistener('install', function(event) { event.waituntil( caches.open('v1').then(function(cache) { return cache.addall([ '/sw-test/', '/sw-test/index.html', '/sw-test/style.css', '/sw-test/app.js', '/sw-test/image-list.js', '/sw-test/star-wars-logo.jpg', '/sw-test/gallery/', '/sw-test/gallery/bountyhunters.jpg', '/sw-test/gal...
Worker: message event - Web APIs
bubbles no cancelable no interface messageevent event handler property onmessage examples this code creates a new worker and listens to messages from it using addeventlistener(): const worker = new worker("static/scripts/worker.js"); worker.addeventlistener('message', (event) => { console.log(`received message from worker: ${event.data}`) }); alternatively, it could listen using the onmessage event handler property: const worker = new worker("static/scripts/worker.js"); worker.onmessage = (event) => { console.log(`received message from worker: ${event.data...
Worker: messageerror event - Web APIs
bubbles no cancelable no interface messageevent event handler property onmessageerror examples create a worker, and listen for message and messageerror events using addeventlistener(): // inside main.js const worker = new worker("static/scripts/worker.js"); worker.addeventlistener("message", (event) => { console.error(`received message from worker: ${event}`); }); worker.addeventlistener("messageerror", (event) => { console.error(`error receiving message from worker: ${event}`); }); the same, but using the onmessageerror event handler property: // inside main.js const worker = new worker("static/scripts/worker.js"); worker.onmes...
Worker.prototype.postMessage() - Web APIs
d code: var myworker = new chromeworker(self.path + 'myworker.js'); function handlemessagefromworker(msg) { console.log('incoming message from worker, msg:', msg); switch (msg.data.atopic) { case 'do_sendmainarrbuff': sendmainarrbuff(msg.data.abuf) break; default: throw 'no atopic on incoming message to chromeworker'; } } myworker.addeventlistener('message', handlemessagefromworker); // ok lets create the buffer and send it var arrbuf = new arraybuffer(8); console.info('arrbuf.bytelength pre transfer:', arrbuf.bytelength); myworker.postmessage( { atopic: 'do_sendworkerarrbuff', abuf: arrbuf // the array buffer that we passed to the transferrable section 3 lines below }, [ arrbuf // the array buffer we ...
WorkerGlobalScope: languagechange event - Web APIs
bubbles no cancelable no interface event event handler onlanguagechange examples you can use the languagechange event in an addeventlistener method: worker.addeventlistener('languagechange', function() { console.log('languagechange event detected!'); }); or use the onlanguagechange event handler property: worker.onlanguagechange = function(event) { console.log('languagechange event detected!'); }; specification specification status html living standardthe definition of 'languagechange' in that specification.
XMLDocument.load() - Web APIs
WebAPIXMLDocumentload
examples var xmldoc = document.implementation.createdocument("", "test", null); function documentloaded (e) { alert(new xmlserializer().serializetostring(e.target)); // gives querydata.xml contents as string } xmldoc.addeventlistener("load", documentloaded, false); xmldoc.load('querydata.xml'); see also the load sample in the xml tests directory.
How to check the security state of an XMLHTTPRequest over SSL - Web APIs
gerprint + "\n"); var validity = cert.validity.queryinterface(ci.nsix509certvalidity); dump("\tvalid from " + validity.notbeforegmt + "\n"); dump("\tvalid until " + validity.notaftergmt + "\n"); } } catch(err) { alert(err); } } function test(url) { var req = cc["@mozilla.org/xmlextras/xmlhttprequest;1"].createinstance(); req.open('get', url, true); req.addeventlistener("error", function(e) { var error = createtcperrorfromfailedxhr(req); dumpsecurityinfo(req, error); }, false); req.onload = function(e) { dumpsecurityinfo(req); }; req.send(); } then test("https://addons.mozilla.org"); produced the following output in my console: connection status: succeeded security info: security state: secure common...
XMLHttpRequest.overrideMimeType() - Web APIs
// interpret the received data as plain text req = new xmlhttprequest(); req.overridemimetype("text/plain"); req.addeventlistener("load", callback, false); req.open("get", url); req.send(); specifications specification status comment xmlhttprequestthe definition of 'overridemimetype()' in that specification.
XMLHttpRequest: timeout event - Web APIs
bubbles no cancelable no interface progressevent event handler property ontimeout examples const client = new xmlhttprequest(); client.open('get', 'http://www.example.org/example.txt'); client.ontimeout = () => { console.error('timeout!!') }; client.send(); you could also set up the event handler using the addeventlistener() method: client.addeventlistener('timeout', () => { console.error("timeout!!"); }); specifications specification status comment xmlhttprequestthe definition of 'timeout event' in that specification.
XMLHttpRequest - Web APIs
more recent browsers, including firefox, also support listening to the xmlhttprequest events via standard addeventlistener() apis in addition to setting on* properties to a handler function.
XRInputSourceEvent() - Web APIs
xrsession.addeventlistener("select", event => { let targetraypose = event.frame.getpose(event.inputsource.targetrayspace, myrefspace); if (targetraypose) { let hit = myhittest(targetraypose.transform); if (hit) { /* handle the hit */ } } }); specifications specification status comment webxr device apithe definition of 'xrinputsourceevent' in that specification.
XRInputSourceEvent - Web APIs
xrsession.addeventlistener("select", event => { let targetraypose = event.frame.getpose(event.inputsource.targetrayspace, myrefspace); if (targetraypose) { let hit = myhittest(targetraypose.transform); if (hit) { /* handle the hit */ } } }); specifications specification status comment webxr device apithe definition of 'xrinputsourceevent' in that specification.
XRInputSourcesChangeEvent - Web APIs
xrsession.addeventlistener("inputsourceschange", oninputsourceschange); function oninputsourceschange(event) { for (let input of event.added) { if (input.targetraymode == "tracked-pointer") { loadcontrollermesh(input); } } } you can also add a handler for inputsourceschange events by setting the oninputsourceschange event handler: xrsession.oninputsourceschange = oninputsourceschange; specifications ...
XRPose.transform - Web APIs
WebAPIXRPosetransform
xrsession.addeventlistener("select", event => { let source = event.inputsource; let frame = event.frame; let targetraypose = frame.getpose(source.targetrayspace, myrefspace); let targetobject = findtargetusingray(targetray.transform.matrix); if (source.targetraymode == "tracked-pointer") { if (source.handedness == user.handedness) { targetobject.primaryaction(); } else { targetobject.offhanda...
XRReferenceSpace.getOffsetReferenceSpace() - Web APIs
canvas.oncontextmenu = (event) => { event.preventdefault(); }; canvas.addeventlistener("mousemove", (event) => { if (event.buttons & 2) { rotateviewby(event.movementx, event.movementy); } }); next, the rotateviewby() function, which updates the mouse look direction's yaw and pitch based on the mouse delta values from the mousemove event.
XRReferenceSpace: reset event - Web APIs
first, you can use the addeventlistener() method: viewerrefspace.addeventlistener("reset", (event) => { /* perform reset related tasks */ }); the second option is to set the xrreferencespace object's onreset event handler property: viewerrefspace.onreset = (event) => { /* perform reset related tasks */ }; specifications specification status comment webxr device apithe definition of 'reset event' in th...
XRReferenceSpace - Web APIs
in addition to using addeventlistener(), you can establish a reset event handler by setting the onreset event handler property.
XRReferenceSpaceEvent.transform - Web APIs
xrreferencespace.addeventlistener("reset", event => { for (let obj of scene.objects) { mat4.multiply(obj.transform, obj.transform, event.transform); } }); specifications specification status comment webxr device apithe definition of 'xrreferencespaceevent.transform' in that specification.
XRRigidTransform.position - Web APIs
example to create a reference space which can be used to place an object at eye level (assuming eye level is 1.5 meters): function onsessionstarted(xrsession) { xrsession.addeventlistener("end", onsessionended); gl = initgraphics(xrsession); let gllayer = new xrwebgllayer(xrsession, gl); xrsession.updaterenderstate({ baselayer: gllayer }); if (immersivesession) { xrsession.requestreferencespace("bounded-floor").then((refspace) => { refspacecreated(refspace); }).catch(() => { session.requestreferencespace("local-floor").then(refspacecreated); }); ...
XRSession: end event - Web APIs
bubbles no cancelable no interface xrsessionevent event handler xrsession.onend example to be informed when a webxr session comes to an end, you can add a handler to your xrsession instance using addeventlistener(), like this: xrsession.addeventlistener("end", function(event) { /* the session has shut down */ }); alternatively, you can use the xrsession.onend event handler property to establish a handler for the end event: xrsession.onend = function(event) { /* the session has shut down */ } specifications specification status comment webxr device apithe definition of ...
XRSession.requestAnimationFrame() - Web APIs
function startxrsession() { navigator.xr.requestsession('immersive-vr').then((session) => { xrsession = session xrsession.addeventlistener('end', onxrsessionended) // do necessary session setup here.
XRSession: visibilitychange event - Web APIs
examples this example demonstrates how to listen for a visibilitychange event on a webxr session, using addeventlistener() to begin listening for the event: navigator.xr.requestsession("inline").then((xrsession) => { xrsession.addeventlistener("visibilitychange", e => { switch(e.session.visiblitystate) { case "visible": case "visible-blurred": mysessionvisible(true); break; case "hidden": mysessionvisible(false); break; } }); }); when a visibility sta...
XRSessionEvent() - Web APIs
xrsession.addeventlistener("visibilitystate", e => { switch(e.session.visibilitystate) { case "visible": case "visible-blurred": mysessionvisible(true); break; case "hidden": mysessionvisible(false); break; } }); specifications specification status comment webxr device apithe definition of 'xrsessionevent() constructor' in that specification.
XRSessionEvent.session - Web APIs
xrsession.addeventlistener("visibilitychange", e => { switch(e.session.visibilitystate) { case "hidden": myenablerendering(true); break; case "visible": case "visible-blurred": myenablerendering(false); break; } }); this calls a function that reacts to the session's visibility state change.
XRSessionEvent - Web APIs
xrsession.addeventlistener("visibilitystate", e => { switch(e.session.visibilitystate) { case "visible": case "visible-blurred": mysessionvisible(true); break; case "hidden": mysessionvisible(false); break; } }); specifications specification status comment webxr device apithe definition of 'xrsessionevent' in that specification.
XRSystem: devicechange event - Web APIs
if (navigator.xr) { navigator.xr.addeventlistener("devicechange", event => { navigator.xr.issessionsupported("immersive-vr") .then(immersiveok) => { if (immersiveok) { enablexrbutton.disabled = false; } else { enablexrbutton.disabled = true; } }); }); } when devicechange is received, the handler set up in this code calls the xr method issessionsupported() to find out if there's a device availabl...
XRSystem: isSessionSupported() - Web APIs
if (navigator.xr) { navigator.xr.issessionsupported('immersive-vr') .then((issupported) => { if (issupported) { userbutton.addeventlistener('click', onbuttonclicked); userbutton.innerhtml = 'enter xr'; userbutton.disabled = false; } }); } function onbuttonclicked() { if (!xrsession) { navigator.xr.requestsession('immersive-vr') .then((session) => { xrsession = session; // onsessionstarted() not shown for reasons of brevity and clarity.
XRSystem - Web APIs
WebAPIXRSystem
if (navigator.xr) { immersivebutton.addeventlistener("click", onbuttonclicked); navigator.xr.issessionsupported('immersive-vr') .then((issupported) => { if (issupported) { immersivebutton.disabled = false; } else { immersivebutton.disabled = true; }); } function onbuttonclicked() { if (!xrsession) { navigator.xr.requestsession('immersive-vr') .then(() => { // onsessionstarted() not shown for reasons of bre...
mssitemodejumplistitemremoved - Web APIs
syntax event property object.oncandidatewindowhide = handler; addeventlistener method object.addeventlistener("mssitemodejumplistitemremoved", handler, usecapture) general info synchronous no bubbles no cancelable no note this event is raised once for every item that has been removed since the last time mssitemodeshowjumplist was called.
ARIA live regions - Accessibility
planets_info) { planettitle.textcontent = planets_info[planet].title; planetdescription.textcontent = planets_info[planet].description; } else { planettitle.textcontent = 'no planet selected'; planetdescription.textcontent = 'select a planet to view its description'; } } const renderplanetinfobutton = document.queryselector('#renderplanetinfobutton'); renderplanetinfobutton.addeventlistener('click', event => { const planetsselect = document.queryselector('#planetsselect'); const selectedplanet = planetsselect.options[planetsselect.selectedindex].value; renderplanetinfo(selectedplanet); }); as the user selects a new planet, the information in the live region will be announced.
Using the link role - Accessibility
e.target : e.srcelement; if (ref) { window.open(ref.getattribute('data-href'), '_blank'); } } } spanelem.addeventlistener('click', navigatelink); spanelem.addeventlistener('keydown', navigatelink); result notes if pressing the link triggers an action but does not change browser focus or navigate to a new page, you might wish to consider using the button role instead of the link role.
ARIA: switch role - Accessibility
document.queryselectorall(".switch").foreach(function(theswitch) { theswitch.addeventlistener("click", handleclickevent, false); }); function handleclickevent(evt) { let el = evt.target; if (el.getattribute("aria-checked") == "true") { el.setattribute("aria-checked", "false"); } else { el.setattribute("aria-checked", "true"); } } css the purpose of the css is to establish a look and feel for the switch that's reminiscent of the power switch paradigm.
ARIA: tab role - Accessibility
window.addeventlistener("domcontentloaded", () => { const tabs = document.queryselectorall('[role="tab"]'); const tablist = document.queryselector('[role="tablist"]'); // add a click event handler to each tab tabs.foreach(tab => { tab.addeventlistener("click", changetabs); }); // enable arrow navigation between tabs in the tab list let tabfocus = 0; tablist.addeventlistener("keydown", e => { /...
Web applications and ARIA FAQ - Accessibility
document.getelementbyid("update-button").addeventlistener("click", function (e) { updateprogress(75); e.preventdefault(); }, false); } initdemo(); how do assistive technologies work?
-webkit-text-stroke-color - CSS: Cascading Style Sheets
pha-value> = <number> | <percentage><hue> = <number> | <angle> examples varying the stroke color html <p>text with stroke</p> <input type="color" value="#ff0000"> css p { margin: 0; font-size: 4em; -webkit-text-stroke-width: 3px; -webkit-text-stroke-color: #ff0000; /* can be changed in the live sample */ } javascript var colorpicker = document.queryselector("input"); colorpicker.addeventlistener("change", function(evt) { document.queryselector("p").style.webkittextstrokecolor = evt.target.value; }); results specifications specification status comment compatibility standardthe definition of '-webkit-text-stroke-color' in that specification.
::before (:before) - CSS: Cascading Style Sheets
WebCSS::before
m; background: lightgrey; font-family: sans-serif; } li.done { background: #ccff99; } li.done::before { content: ''; position: absolute; border-color: #009933; border-style: solid; border-width: 0 0.3em 0.25em 0; height: 1em; top: 1.3em; left: 0.6em; margin-top: -1em; transform: rotate(45deg); width: 0.5em; } javascript var list = document.queryselector('ul'); list.addeventlistener('click', function(ev) { if (ev.target.tagname === 'li') { ev.target.classlist.toggle('done'); } }, false); here is the above code example running live.
:disabled - CSS: Cascading Style Sheets
WebCSS:disabled
shipping address:</label> <input type="checkbox" id="billing-checkbox" checked> <br> <input type="text" placeholder="name" disabled> <input type="text" placeholder="address" disabled> <input type="text" placeholder="zip code" disabled> </fieldset> </form> css input[type="text"]:disabled { background: #ccc; } javascript // wait for the page to finish loading document.addeventlistener('domcontentloaded', function () { // attach `change` event listener to checkbox document.getelementbyid('billing-checkbox').onchange = togglebilling; }, false); function togglebilling() { // select the billing text fields var billingitems = document.queryselectorall('#billing input[type="text"]'); // toggle the billing text fields for (var i = 0; i < billingitems.length; i++) { ...
:first - CSS: Cascading Style Sheets
WebCSS:first
syntax :first examples html <p>first page.</p> <p>second page.</p> <button>print!</button> css @page :first { margin-left: 50%; margin-top: 50%; } p { page-break-after: always; } javascript document.queryselector("button").addeventlistener('click', () => { window.print(); }); result press the "print!" button to print the example.
:is() (:matches(), :any()) - CSS: Cascading Style Sheets
WebCSS:is
matcheditems = document.queryselectorall(':-webkit-any(header, main, footer) p'); } catch(e) { try { matcheditems = document.queryselectorall(':-moz-any(header, main, footer) p'); } catch(e) { console.log('your browser doesn\'t support :is(), :matches(), or :any()'); } } } } matcheditems.foreach(applyhandler); function applyhandler(elem) { elem.addeventlistener('click', function(e) { alert('this paragraph is inside a ' + e.target.parentnode.nodename); }); } simplifying list selectors the :is() pseudo-class can greatly simplify your css selectors.
Using CSS animations - CSS: Cascading Style Sheets
var element = document.getelementbyid("watchme"); element.addeventlistener("animationstart", listener, false); element.addeventlistener("animationend", listener, false); element.addeventlistener("animationiteration", listener, false); element.classname = "slidein"; this is pretty standard code; you can get details on how it works in the documentation for eventtarget.addeventlistener().
align-content - CSS: Cascading Style Sheets
n value="safe end">safe end</option> <option value="unsafe end">unsafe end</option> <option value="safe flex-end">safe flex-end</option> <option value="unsafe flex-end">unsafe flex-end</option> </select> </div> javascript var values = document.getelementbyid('values'); var display = document.getelementbyid('display'); var container = document.getelementbyid('container'); values.addeventlistener('change', function (evt) { container.style.aligncontent = evt.target.value; }); display.addeventlistener('change', function (evt) { container.classname = evt.target.value; }); result specifications specification status comment css box alignment module level 3the definition of 'align-content' in that specification.
align-items - CSS: Cascading Style Sheets
nd">safe self-end</option> <option value="unsafe self-end">unsafe self-end</option> <option value="safe flex-end">safe flex-end</option> <option value="unsafe flex-end">unsafe flex-end</option> </select> </div> javascript var values = document.getelementbyid('values'); var display = document.getelementbyid('display'); var container = document.getelementbyid('container'); values.addeventlistener('change', function (evt) { container.style.alignitems = evt.target.value; }); display.addeventlistener('change', function (evt) { container.classname = evt.target.value; }); result specifications specification status comment css box alignment module level 3the definition of 'align-items' in that specification.
<blend-mode> - CSS: Cascading Style Sheets
<option>luminosity</option> </select> css div { width: 300px; height: 300px; background: url(https://media.prod.mdn.mozit.cloud/attachments/2020/07/29/17350/3b4892b7e820122ac6dd7678891d4507/firefox.png) no-repeat center, linear-gradient(to bottom, blue, orange); } javascript const selectelem = document.queryselector('select'); const divelem = document.queryselector('div'); selectelem.addeventlistener('change', () => { divelem.style.backgroundblendmode = selectelem.value; }); result specifications specification status comment compositing and blending level 1the definition of '<blend-mode>' in that specification.
border-image-repeat - CSS: Cascading Style Sheets
on me!</div> <select id="repetition"> <option value="stretch">stretch</option> <option value="repeat">repeat</option> <option value="round">round</option> <option value="space">space</option> <option value="stretch repeat">stretch repeat</option> <option value="space round">space round</option> </select> javascript var repetition = document.getelementbyid("repetition"); repetition.addeventlistener("change", function (evt) { document.getelementbyid("bordered").style.borderimagerepeat = evt.target.value; }); results specifications specification status comment css backgrounds and borders module level 3the definition of 'border-image-repeat' in that specification.
border-image-slice - CSS: Cascading Style Sheets
ice: 30; border-image-repeat: round; } li { display: flex; place-content: center; } javascript const widthslider = document.getelementbyid('width'); const sliceslider = document.getelementbyid('slice'); const widthoutput = document.getelementbyid('width-output'); const sliceoutput = document.getelementbyid('slice-output'); const divelem = document.queryselector('div > div'); widthslider.addeventlistener('input', () => { const newvalue = widthslider.value + 'px'; divelem.style.borderwidth = newvalue; widthoutput.textcontent = newvalue; }) sliceslider.addeventlistener('input', () => { const newvalue = sliceslider.value; divelem.style.borderimageslice = newvalue; sliceoutput.textcontent = newvalue; }) result specifications specification status comment c...
clip-path - CSS: Cascading Style Sheets
WebCSSclip-path
110px 100px)">circle</option> <option value="url(#cross)" selected>cross</option> <option value="inset(20px round 20px)">inset</option> <option value="path('m 0 200 l 0,110 a 110,90 0,0,1 240,100 l 200 340 z')">path</option> </select> css #clipped { margin-bottom: 20px; clip-path: url(#cross); } javascript const clippathselect = document.getelementbyid("clippath"); clippathselect.addeventlistener("change", function (evt) { document.getelementbyid("clipped").style.clippath = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'clip-path' in that specification.
<color> - CSS: Cascading Style Sheets
eturn false; } if (stringtotest === "transparent") { return false; } const image = document.createelement("img"); image.style.color = "rgb(0, 0, 0)"; image.style.color = stringtotest; if (image.style.color !== "rgb(0, 0, 0)") { return true; } image.style.color = "rgb(255, 255, 255)"; image.style.color = stringtotest; return image.style.color !== "rgb(255, 255, 255)"; } inputelem.addeventlistener('change', () => { if(validtextcolor(inputelem.value)) { divelem.style.backgroundcolor = inputelem.value; divelem.textcontent = ''; } else { divelem.style.backgroundcolor = 'white'; divelem.textcontent = 'invalid color value'; } }); result rgb syntax variations this example shows the many ways in which a single color can be created with the various rgb color syntaxes.
display - CSS: Cascading Style Sheets
WebCSSdisplay
span { background-color: black; color: white; margin: 1px; } article, span { padding: 10px; border-radius: 7px; } article, div { margin: 20px; } javascript const articles = document.queryselectorall('.container'); const select = document.queryselector('select'); function updatedisplay() { articles.foreach((article) => { article.style.display = select.value; }); } select.addeventlistener('change', updatedisplay); updatedisplay(); result note: you can find more examples in the pages for each separate display data type, linked above.
<easing-function> - CSS: Cascading Style Sheets
animation: 1.5s infinite alternate; } @keyframes move-right { from { left: 10%; } to { left: 90%; } } li { display: flex; align-items: center; justify-content: center; margin-bottom: 20px; } javascript const selectelem = document.queryselector('select'); const startbtn = document.queryselector('button'); const divelem = document.queryselector('div > div'); startbtn.addeventlistener('click', () => { if(startbtn.textcontent === 'start animation') { divelem.style.animationname = 'move-right'; startbtn.textcontent = 'stop animation'; divelem.style.animationtimingfunction = selectelem.value; } else { divelem.style.animationname = 'unset'; startbtn.textcontent = 'start animation'; } }); selectelem.addeventlistener('change', () => { divelem.style.anima...
<filter-function> - CSS: Cascading Style Sheets
: 20px; } input { width: 60% } output { width: 5%; text-align: center; } select { width: 40%; margin-left: 2px; } javascript const selectelem = document.queryselector('select'); const divelem = document.queryselector('div'); const slider = document.queryselector('input'); const output = document.queryselector('output'); const curvalue = document.queryselector('p code'); selectelem.addeventlistener('change', () => { setslider(selectelem.value); setdiv(selectelem.value); }); slider.addeventlistener('input', () => { setdiv(selectelem.value); }); function setslider(filter) { if(filter === 'blur') { slider.value = 0; slider.min = 0; slider.max = 30; slider.step = 1; slider.setattribute('data-unit', 'px'); } else if(filter === 'brightness' || filter === 'contrast'...
flex - CSS: Cascading Style Sheets
WebCSSflex
-container"> <div class="flex-item" id="flex">flex box (click to toggle raw box)</div> <div class="raw-item" id="raw">raw box</div> </div> css #flex-container { display: flex; flex-direction: row; } #flex-container > .flex-item { flex: auto; } #flex-container > .raw-item { width: 5rem; } var flex = document.getelementbyid("flex"); var raw = document.getelementbyid("raw"); flex.addeventlistener("click", function() { raw.style.display = raw.style.display == "none" ?
font-kerning - CSS: Cascading Style Sheets
ij</textarea> css div { font-size: 2rem; font-family: serif; } #nokern { font-kerning: none; } #kern { font-kerning: normal; } javascript let input = document.getelementbyid('input'); let kern = document.getelementbyid('kern'); let nokern = document.getelementbyid('nokern'); input.addeventlistener('keyup', function() { kern.textcontent = input.value; /* update content */ nokern.textcontent = input.value; }); kern.textcontent = input.value; /* initialize content */ nokern.textcontent = input.value; specifications specification status comment css fonts module level 3the definition of 'font-kerning' in that specification.
font-style - CSS: Cascading Style Sheets
> p { margin-top: 0; margin-bottom: 0; } javascript let slantlabel = document.queryselector('label[for="slant"]'); let slantinput = document.queryselector('#slant'); let sampletext = document.queryselector('.sample'); function update() { let slant = `oblique ${slantinput.value}deg`; slantlabel.textcontent = `font-style: ${slant};`; sampletext.style.fontstyle = slant; } slantinput.addeventlistener('input', update); update(); accessibility concerns large sections of text set with a font-style value of italic may be difficult for people with cognitive concerns such as dyslexia to read.
font-weight - CSS: Cascading Style Sheets
1; } .container > p { margin-top: 0; margin-bottom: 0; } javascript let weightlabel = document.queryselector('label[for="weight"]'); let weightinput = document.queryselector('#weight'); let sampletext = document.queryselector('.sample'); function update() { weightlabel.textcontent = `font-weight: ${weightinput.value};`; sampletext.style.fontweight = weightinput.value; } weightinput.addeventlistener('input', update); update(); accessibility concerns people experiencing low vision conditions may have difficulty reading text set with a font-weight value of 100 (thin/hairline) or 200 (extra light), especially if the font has a low contrast color ratio.
image-orientation - CSS: Cascading Style Sheets
/* can be changed in the live sample */ } html <img id="image" src="https://udn.realityripple.com/samples/db/4f9fbd7dfb.svg" alt="orientation taken from the image"> <select id="imageorientation"> <option value="from-image">from-image</option> <option value="none">none</option> </select> javascript var imageorientation = document.getelementbyid("imageorientation"); imageorientation.addeventlistener("change", function (evt) { document.getelementbyid("image").style.imageorientation = evt.target.value; }); result specifications specification status comment css images module level 3the definition of 'image-orientation' in that specification.
justify-content - CSS: Cascading Style Sheets
line">first baseline</option> <option value="last baseline">last baseline</option> <option value="space-between" selected>space-between</option> <option value="space-around">space-around</option> <option value="space-evenly">space-evenly</option> <option value="stretch">stretch</option> </select> javascript var justifycontent = document.getelementbyid("justifycontent"); justifycontent.addeventlistener("change", function (evt) { document.getelementbyid("container").style.justifycontent = evt.target.value; }); result specifications specification status comment css box alignment module level 3the definition of 'justify-content' in that specification.
<length> - CSS: Cascading Style Sheets
WebCSSlength
gin-left: 20px; } .results { margin-top: 10px; } .input-container { position: absolute; display: flex; justify-content: flex-start; align-items: center; height: 50px; } label { margin: 0 10px 0 20px; } javascript const inputdiv = document.queryselector('.inner'); const inputelem = document.queryselector('input'); const resultsdiv = document.queryselector('.results'); inputelem.addeventlistener('change', () => { inputdiv.style.width = inputelem.value; const result = document.createelement('div'); result.classname = 'result'; result.style.width = inputelem.value; result.innerhtml = `<code>width: ${inputelem.value}</code>`; resultsdiv.appendchild(result); inputelem.value = ''; inputelem.focus(); }) result specifications specification status comment ...
mask-clip - CSS: Cascading Style Sheets
WebCSSmask-clip
ng-box">padding-box</option> <option value="border-box" selected>border-box</option> <option value="margin-box">margin-box</option> <option value="fill-box">fill-box</option> <option value="stroke-box">stroke-box</option> <option value="view-box">view-box</option> <option value="no-clip">no-clip</option> </select> javascript var clipbox = document.getelementbyid("clipbox"); clipbox.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.maskclip = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'mask-clip' in that specification.
mask-composite - CSS: Cascading Style Sheets
ze: 100% 100%; mask-composite: add; /* can be changed in the live sample */ } html <div id="masked"> </div> <select id="compositemode"> <option value="add">add</option> <option value="subtract">subtract</option> <option value="intersect">intersect</option> <option value="exclude">exclude</option> </select> javascript var clipbox = document.getelementbyid("compositemode"); clipbox.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.maskcomposite = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'mask-composite' in that specification.
mask-mode - CSS: Cascading Style Sheets
WebCSSmask-mode
: url(https://mdn.mozillademos.org/files/12668/mdn.svg); mask-mode: alpha; /* can be changed in the live sample */ } html <div id="masked"> </div> <select id="maskmode"> <option value="alpha">alpha</option> <option value="luminance">luminance</option> <option value="match-source">match-source</option> </select> javascript var maskmode = document.getelementbyid("maskmode"); maskmode.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.maskmode = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'mask-mode' in that specification.
mask-origin - CSS: Cascading Style Sheets
x">content-box</option> <option value="padding-box">padding-box</option> <option value="border-box" selected>border-box</option> <option value="margin-box">margin-box</option> <option value="fill-box">fill-box</option> <option value="stroke-box">stroke-box</option> <option value="view-box">view-box</option> </select> javascript var origin = document.getelementbyid("origin"); origin.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.maskorigin = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'mask-origin' in that specification.
mask-position - CSS: Cascading Style Sheets
</option> <option value="bottom">bottom</option> <option value="top right" selected>top right</option> <option value="center center">center center</option> <option value="bottom left">bottom left</option> <option value="10px 20px">10px 20px</option> <option value="60% 20%">60% 20%</option> </select> javascript var maskposition = document.getelementbyid("maskposition"); maskposition.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.maskposition = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'mask-position' in that specification.
mask-repeat - CSS: Cascading Style Sheets
d"> </div> <select id="repetition"> <option value="repeat-x">repeat-x</option> <option value="repeat-y">repeat-y</option> <option value="repeat" selected>repeat</option> <option value="space">space</option> <option value="round">round</option> <option value="no-repeat">no-repeat</option> </select> javascript content var repetition = document.getelementbyid("repetition"); repetition.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.maskrepeat = evt.target.value; }); result multiple mask image support you can specify a different <repeat-style> for each mask image, separated by commas: .examplethree { mask-image: url('mask1.png'), url('mask2.png'); mask-repeat: repeat-x, repeat-y; } each image is matched with the corresponding repeat style, fro...
mask-size - CSS: Cascading Style Sheets
WebCSSmask-size
html <div id="masked"> </div> <select id="masksize"> <option value="auto">auto</option> <option value="40% 80%">40% 80%</option> <option value="50%" selected>50%</option> <option value="200px 100px">200px 100px</option> <option value="cover">cover</option> <option value="contain">contain</option> </select> javascript var masksize = document.getelementbyid("masksize"); masksize.addeventlistener("change", function (evt) { document.getelementbyid("masked").style.masksize = evt.target.value; }); result specifications specification status comment css masking module level 1the definition of 'mask-size' in that specification.
place-items - CSS: Cascading Style Sheets
al</option> <option value="first baseline auto">first baseline auto</option> <option value="last baseline normal">last baseline normal</option> <option value="stretch auto">stretch auto</option> </select> </div> javascript var values = document.getelementbyid('values'); var display = document.getelementbyid('display'); var container = document.getelementbyid('container'); values.addeventlistener('change', function (evt) { container.style.placeitems = evt.target.value; }); display.addeventlistener('change', function (evt) { container.classname = evt.target.value; }); css #container { height:200px; width: 240px; place-items: center; /* you can change this value by selecting another option in the list */ background-color: #8c8c8c; } .flex { display: flex; flex-wrap: wr...
<transform-function> - CSS: Cascading Style Sheets
rm: rotatey(-90deg) translatez(50px); } .top { background: rgba(210,210,0,.7); transform: rotatex(90deg) translatez(50px); } .bottom { background: rgba(210,0,210,.7); transform: rotatex(-90deg) translatez(50px); } .select-form { margin-top: 50px; } javascript const selectelem = document.queryselector('select'); const example = document.queryselector('#example-element'); selectelem.addeventlistener('change', () => { if(selectelem.value === 'choose a function') { return; } else { example.style.transform = `rotate3d(1, 1, 1, 30deg) ${selectelem.value}`; settimeout(function() { example.style.transform = 'rotate3d(1, 1, 1, 30deg)'; }, 2000) } }) result specifications specification status comment css transforms level 2the definition of...
transform-style - CSS: Cascading Style Sheets
background: rgba(0,0,210,.7); transform: rotatey(-90deg) translatez(50px); } .top { background: rgba(210,210,0,.7); transform: rotatex(90deg) translatez(50px); } .bottom { background: rgba(210,0,210,.7); transform: rotatex(-90deg) translatez(50px); } javascript const cube = document.getelementbyid('example-element'); const checkbox = document.getelementbyid('preserve'); checkbox.addeventlistener('change', () => { if(checkbox.checked) { cube.style.transformstyle = 'preserve-3d'; } else { cube.style.transformstyle = 'flat'; } }) result specifications specification status comment css transforms level 2the definition of 'transform-style' in that specification.
Used value - CSS: Cascading Style Sheets
avascript function updateusedwidth(id) { var div = document.queryselector(`#${id}`); var par = div.queryselector('.show-used-width'); var wid = window.getcomputedstyle(div)["width"]; par.textcontent = `used width: ${wid}.`; } function updateallusedwidths() { updateusedwidth("no-width"); updateusedwidth("width-50"); updateusedwidth("width-inherit"); } updateallusedwidths(); window.addeventlistener('resize', updateallusedwidths); result difference from computed value css 2.0 defined only computed value as the last step in a property's calculation.
white-space - CSS: Cascading Style Sheets
#css-code { background-color: rgb(220, 220, 220); font-size: 16px; font-family: monospace; } #css-code select { font-family: inherit; } #results { background-color: rgb(230, 230, 230); overflow-x: scroll; height: 400px; white-space: normal; font-size: 14px; } var select = document.queryselector("#css-code select"); var results = document.queryselector("#results p"); select.addeventlistener("change", function(e) { results.setattribute("style", "white-space: "+e.target.value); }) <p> lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
will-change - CSS: Cascading Style Sheets
var el = document.getelementbyid('element'); // set will-change when the element is hovered el.addeventlistener('mouseenter', hintbrowser); el.addeventlistener('animationend', removehint); function hintbrowser() { // the optimizable properties that are going to change // in the animation's keyframes block this.style.willchange = 'transform, opacity'; } function removehint() { this.style.willchange = 'auto'; } specifications specification status comment css will chang...
Getting Started - Developer guides
<button id="ajaxbutton" type="button">make a request</button> <script> (function() { var httprequest; document.getelementbyid("ajaxbutton").addeventlistener('click', makerequest); function makerequest() { httprequest = new xmlhttprequest(); if (!httprequest) { alert('giving up :( cannot create an xmlhttp instance'); return false; } httprequest.onreadystatechange = alertcontents; httprequest.open('get', 'test.html'); httprequest.send(); } function alertcontents() { if (httprequest.readystate === xmlhttp...
Web Audio playbackRate explained - Developer guides
5b/8cd6da9c65.webm" type='video/webm' /> </video> <form> <input id="pbr" type="range" value="1" min="0.5" max="4" step="0.1" > <p>playback rate <span id="currentpbr">1</span></p> </form> and apply some javascript to it: window.onload = function () { var v = document.getelementbyid("myvideo"); var p = document.getelementbyid("pbr"); var c = document.getelementbyid("currentpbr"); p.addeventlistener('input',function(){ c.innerhtml = p.value; v.playbackrate = p.value; },false); }; finally, we listen for the input event firing on the <input> element, allowing us to react to the playback rate control being changed.
Media events - Developer guides
you can easily watch for these events, using code such as the following: var v = document.getelementsbytagname("video")[0]; v.addeventlistener("seeked", function() { v.play(); }, true); v.currenttime = 10.0; this example fetches the first video element in the document and attaches an event listener to it, watching for the seeked event, which is sent whenever a seek operation completes.
Mutation events - Developer guides
ement, removed)) { callback(); // allow garbage collection observer.disconnect(); observer = undefined; } }); }); }); observer.observe(document, { childlist: true, subtree: true }); }; usage you can register a listener for mutation events using element.addeventlistener as follows: element.addeventlistener("domnodeinserted", function (event) { // ...
Event developer guide - Developer guides
WebGuideEvents
two common styles are: the generalized addeventlistener() and a set of specific on-event handlers.media eventsvarious events are sent when handling media that are embedded in html documents using the <audio> and <video> elements; this section lists them and provides some helpful information about using them.mouse gesture eventsgecko 1.9.1 added support for several mozilla-specific dom events used to handle mouse gestures.
Index - Developer guides
WebGuideIndex
two common approaches are addeventlistener() and the specific onevent handlers.
Printing - Developer guides
note: you can also use window.onbeforeprint and window.onafterprint to assign handlers for these events, but using eventtarget.addeventlistener() is preferred.
Applying color to HTML elements using CSS - HTML: Hypertext Markup Language
let colorpicker = document.getelementbyid("colorpicker"); let box = document.getelementbyid("box"); let output = document.getelementbyid("output"); box.style.bordercolor = colorpicker.value; colorpicker.addeventlistener("input", function(event) { box.style.bordercolor = event.target.value; }, false); colorpicker.addeventlistener("change", function(event) { output.innertext = "color set to " + colorpicker.value + "."; }, false); the input event is sent every time the value of the element changes; that is, every time the user adjusts the color in the color picker.
Allowing cross-origin use of images and canvas - HTML: Hypertext Markup Language
starting the download the code that starts the download (say, when the user clicks a "download" button), looks like this: function startdownload() { let imageurl = "https://cdn.glitch.com/4c9ebeb9-8b9a-4adc-ad0a-238d9ae00bb5%2fmdn_logo-only_color.svg?1535749917189"; downloadedimg = new image; downloadedimg.crossorigin = "anonymous"; downloadedimg.addeventlistener("load", imagereceived, false); downloadedimg.src = imageurl; } we're using a hard-coded url here (imageurl), but that could easily come from anywhere.
<a>: The Anchor element - HTML: Hypertext Markup Language
WebHTMLElementa
anvas { background: #fff; border: 1px dashed; } a { display: inline-block; background: #69c; color: #fff; padding: 5px 10px; } javascript var canvas = document.queryselector('canvas'), c = canvas.getcontext('2d'); c.fillstyle = 'hotpink'; function draw(x, y) { if (isdrawing) { c.beginpath(); c.arc(x, y, 10, 0, math.pi*2); c.closepath(); c.fill(); } } canvas.addeventlistener('mousemove', event => draw(event.offsetx, event.offsety) ); canvas.addeventlistener('mousedown', () => isdrawing = true); canvas.addeventlistener('mouseup', () => isdrawing = false); document.queryselector('a').addeventlistener('click', event => event.target.href = canvas.todataurl() ); result security and privacy <a> elements can have consequences for users’ security and privacy.
<audio>: The Embed Audio element - HTML: Hypertext Markup Language
WebHTMLElementaudio
you can also use addeventlistener() to listen for the addtrack and removetrack events.
<details>: The Details disclosure element - HTML: Hypertext Markup Language
WebHTMLElementdetails
you can use an event listener for the toggle event to detect when the widget changes state: details.addeventlistener("toggle", event => { if (details.open) { /* the element was toggled open */ } else { /* the element was toggled closed */ } }); examples a simple disclosure example this example shows a <details> element with no provided summary.
<input type="file"> - HTML: Hypertext Markup Language
WebHTMLElementinputfile
input.addeventlistener('change', updateimagedisplay); whenever the updateimagedisplay() function is invoked, we: use a while loop to empty the previous contents of the preview <div>.
<input type="number"> - HTML: Hypertext Markup Language
WebHTMLElementinputnumber
5px; } and finally, the javascript: let metersinputgroup = document.queryselector('.metersinputgroup'); let feetinputgroup = document.queryselector('.feetinputgroup'); let metersinput = document.queryselector('#meters'); let feetinput = document.queryselector('#feet'); let inchesinput = document.queryselector('#inches'); let switchbtn = document.queryselector('input[type="button"]'); switchbtn.addeventlistener('click', function() { if(switchbtn.getattribute('class') === 'meters') { switchbtn.setattribute('class', 'feet'); switchbtn.value = 'enter height in meters'; metersinputgroup.style.display = 'none'; feetinputgroup.style.display = 'block'; feetinput.setattribute('required', ''); inchesinput.setattribute('required', ''); metersinput.removeattribute('required'); ...
<input type="radio"> - HTML: Hypertext Markup Language
WebHTMLElementinputradio
name="contact" value="mail"> <label for="contactchoice3">mail</label> </div> <div> <button type="submit">submit</button> </div> </form> <pre id="log"> </pre> then we add some javascript to set up an event listener on the submit event, which is sent when the user clicks the "submit" button: var form = document.queryselector("form"); var log = document.queryselector("#log"); form.addeventlistener("submit", function(event) { var data = new formdata(form); var output = ""; for (const entry of data) { output = output + entry[0] + "=" + entry[1] + "\r"; }; log.innertext = output; event.preventdefault(); }, false); try this example out and see how there's never more than one result for the contact group.
<input type="time"> - HTML: Hypertext Markup Language
WebHTMLElementinputtime
var starttime = document.getelementbyid("starttime"); var valuespan = document.getelementbyid("value"); starttime.addeventlistener("input", function() { valuespan.innertext = starttime.value; }, false); when a form including a time input is submitted, the value is encoded before being included in the form's data.
<input>: The Input (Form Input) element - HTML: Hypertext Markup Language
WebHTMLElementinput
if you wanted to instead display custom error messages, you could use javascript like the following: const nameinput = document.queryselector('input'); const form = document.queryselector('form'); nameinput.addeventlistener('input', () => { nameinput.setcustomvalidity(''); nameinput.checkvalidity(); }); nameinput.addeventlistener('invalid', () => { if(nameinput.value === '') { nameinput.setcustomvalidity('enter your username!'); } else { nameinput.setcustomvalidity('usernames can only contain upper and lowercase letters.
<p>: The Paragraph element - HTML: Hypertext Markup Language
WebHTMLElementp
switch back!">use pilcrow for paragraphs</button> </p> css p { margin: 0; text-indent: 3ch; } p.pilcrow { text-indent: 0; display: inline; } p.pilcrow + p.pilcrow::before { content: " ¶ "; } javascript document.queryselector('button').addeventlistener('click', function (event) { document.queryselectorall('p').foreach(function (paragraph) { paragraph.classlist.toggle('pilcrow'); }); var newbuttontext = event.target.dataset.toggletext; var oldtext = event.target.innertext; event.target.innertext = newbuttontext; event.target.dataset.toggletext = oldtext; }); result accessibility concerns breaking up content into paragraphs h...
<template>: The Content Template element - HTML: Hypertext Markup Language
WebHTMLElementtemplate
consider the following html and javascript: html <div id="container"></div> <template id="template"> <div>click me</div> </template> javascript const container = document.getelementbyid("container"); const template = document.getelementbyid("template"); function clickhandler(event) { alert("clicked a div"); } const firstclone = template.content.clonenode(true); firstclone.addeventlistener("click", clickhandler); container.appendchild(firstclone); const secondclone = template.content.firstelementchild.clonenode(true); secondclone.addeventlistener("click", clickhandler); container.appendchild(secondclone); result firstclone is a documentfragment instance, so while it gets appended inside the container as expected, clicking on it does not trigger the click event.
<track>: The Embed Text Track element - HTML: Hypertext Markup Language
WebHTMLElementtrack
let texttrackelem = document.getelementbyid("texttrack"); texttrackelem.addeventlistener("cuechange", (event) => { let cues = event.target.track.activecues; }); in addition, you can use the oncuechange event handler: let texttrackelem = document.getelementbyid("texttrack"); texttrackelem.oncuechange = (event) => { let cues = event.target.track.activecues; }); examples <video controls poster="/images/sample.gif"> <source src="sample.mp4" type="video/mp4"> <source src="...
<video>: The Video Embed element - HTML: Hypertext Markup Language
WebHTMLElementvideo
you can also use addeventlistener() to listen for the addtrack and removetrack events.
Using the application cache - HTML: Hypertext Markup Language
function onupdateready() { console.log('found new version!'); } window.applicationcache.addeventlistener('updateready', onupdateready); if(window.applicationcache.status === window.applicationcache.updateready) { onupdateready(); } to manually start testing for a new manifest file, you can use window.applicationcache.update().
CSP: script-src - HTTP
examples violation case given this csp header: content-security-policy: script-src https://example.com/ the following script is blocked and won't be loaded or executed: <script src="https://not-example.com/js/library.js"></script> note that inline event handlers are blocked as well: <button id="btn" onclick="dosomething()"> you should replace them with addeventlistener calls: document.getelementbyid("btn").addeventlistener('click', dosomething); unsafe inline script note: disallowing inline styles and inline scripts is one of the biggest security wins csp provides.
Loops and iteration - JavaScript
ion>opera</option> </select> </p> <p><input id="btn" type="button" value="how many are selected?" /></p> </form> <script> function howmany(selectobject) { let numberselected = 0; for (let i = 0; i < selectobject.options.length; i++) { if (selectobject.options[i].selected) { numberselected++; } } return numberselected; } let btn = document.getelementbyid('btn'); btn.addeventlistener('click', function() { alert('number of options selected: ' + howmany(document.selectform.musictypes)); }); </script> do...while statement the do...while statement repeats until a specified condition evaluates to false.
JavaScript modules - JavaScript
over in main.js we've grabbed a reference to each button using a document.queryselector() call, for example: let squarebtn = document.queryselector('.square'); we then attach an event listener to each button so that when pressed, the relevant module is dynamically loaded and used to draw the shape: squarebtn.addeventlistener('click', () => { import('./modules/square.js').then((module) => { let square1 = new module.square(mycanvas.ctx, mycanvas.listid, 50, 50, 100, 'blue'); square1.draw(); square1.reportarea(); square1.reportperimeter(); }) }); note that, because the promise fulfillment returns a module object, the class is then made a subfeature of the object, hence we now need to access the cons...
Using Promises - JavaScript
you can capture these for analysis and handling by your code—or just to avoid having them cluttering up your output—by adding a handler for the unhandledrejection event, like this: window.addeventlistener("unhandledrejection", event => { /* you might start here by adding code to examine the promise specified by event.promise and the reason in event.reason */ event.preventdefault(); }, false); by calling the event's preventdefault() method, you tell the javascript runtime not to do its default action when rejected promises go unhandled.
Memory Management - JavaScript
for a number var s = 'azerty'; // allocates memory for a string var o = { a: 1, b: null }; // allocates memory for an object and contained values // (like object) allocates memory for the array and // contained values var a = [1, null, 'abra']; function f(a) { return a + 2; } // allocates a function (which is a callable object) // function expressions also allocate an object someelement.addeventlistener('click', function() { someelement.style.backgroundcolor = 'blue'; }, false); allocation via function calls some function calls result in object allocation.
Error.prototype.lineNumber - JavaScript
examples using linenumber var e = new error('could not parse input'); throw e; console.log(e.linenumber) // 2 alternative example using error event window.addeventlistener('error', function(e) { console.log(e.linenumber); // 5 }); var e = new error('could not parse input'); throw e; this is not a standard feature and lacks widespread support.
Promise - JavaScript
sertadjacenthtml('beforeend', val + ') promise fulfilled (async code terminated)'); }).catch((reason) => { // log the rejection reason console.log(`handle rejected promise (${reason}) here.`); }); // end log.insertadjacenthtml('beforeend', thispromisecount + ') promise made (sync code terminated)'); } if ("promise" in window) { let btn = document.getelementbyid("btn"); btn.addeventlistener("click",testpromise); } else { log = document.getelementbyid('log'); log.innerhtml = "live example not available as your browser doesn't support the <code>promise<code> interface."; } this example is started by clicking the button.
eval() - JavaScript
}, 1000); // instead of elt.setattribute("onclick", "...") use: elt.addeventlistener('click', function() { ...
Function expression - JavaScript
the function returns the square of its argument: var x = function(y) { return y * y; }; using a function as a callback more commonly it is used as a callback: button.addeventlistener('click', function(event) { console.log('button is clicked!') }) using an immediately executed function expression an anonymous function is created and called: (function() { console.log('code runs!') })(); specifications specification ecmascript (ecma-262)the definition of 'function definitions' in that specification.
import - JavaScript
const main = document.queryselector("main"); for (const link of document.queryselectorall("nav > a")) { link.addeventlistener("click", e => { e.preventdefault(); import('/modules/my-module.js') .then(module => { module.loadpageinto(main); }) .catch(err => { main.textcontent = err.message; }); }); } specifications specification ecmascript (ecma-262)the definition of 'imports' in that specification.
Codecs used by WebRTC - Web media technologies
let codeclist = null; peerconnection.addeventlistener("icegatheringstatechange", (event) => { if (peerconnection.icegatheringstate === "complete") { const senders = peerconnection.getsenders(); senders.foreach((sender) => { if (sender.track.kind === "video") { codeclist = sender.getparameters().codecs; return; } }); } codeclist = null; }); the event handler for icegatheringstatechange is established; ...
pointer-events - SVG: Scalable Vector Graphics
the rect underneath will change color whether you are clicking on the circle or the rect itself --> <rect x="10" y="0" height="10" width="10" fill="black" /> <circle cx="15" cy="5" r="4" fill="white" pointer-events="none" /> </svg> window.addeventlistener('mouseup', (e) => { // let's pick a random color between #000000 and #ffffff const color = math.round(math.random() * 0xffffff) // let's format the color to fit css requirements const fill = '#' + color.tostring(16).padstart(6,'0') // let's apply our color in the // element we actually clicked on e.target.style.fill = fill }) as a presentation attribute, it can be applied to a...
restart - SVG: Scalable Vector Graphics
WebSVGAttributerestart
pe="xml" attributename="y" from="30" to="100" dur="5s" repeatcount="1" restart="always" /> </rect> <rect x="120" y="30" width="100" height="100"> <animate attributetype="xml" attributename="y" from="30" to="100" dur="5s" repeatcount="1" restart="whennotactive"/> </rect> <a id="restart"><text y="20">restart animation</text></a> </svg> document.getelementbyid("restart").addeventlistener("click", evt => { document.queryselectorall("animate").foreach(element => { element.beginelement(); }); }); usage notes value always | whennotactive | never default value always animatable no always this value indicates that the animation can be restarted at any time.
textLength - SVG: Scalable Vector Graphics
it starts by stashing references to the elements it will need to access, using document.getelementbyid(): const widthslider = document.getelementbyid("widthslider"); const widthdisplay = document.getelementbyid("widthdisplay"); const textelement = document.getelementbyid("hello"); const baselength = math.floor(textelement.textlength.baseval.value); widthslider.value = baselength; widthslider.addeventlistener("input", function(event) { textelement.textlength.baseval.newvaluespecifiedunits( svglength.svg_lengthtype_px, widthslider.valueasnumber); widthdisplay.innertext = widthslider.value; }, false); widthslider.dispatchevent(new event("input")); after fetching the element references, an eventlistener is established by calling addeventlistener() on the slider control, to receive any input...
visibility - SVG: Scalable Vector Graphics
.17 7.41 8.59 6 10l6 6 6-6z" /> <path d="m12 8l-6 6 1.41 1.41l12 10.83l4.59 4.58l18 14z" class="invisible" /> <path d="m0 0h24v24h0z" fill="none" /> </svg> <span> click me </span> </button> css svg { display: inline !important; } span { vertical-align: 50%; } button { line-height: 1em; } .invisible { visibility: hidden; } javascript document.queryselector("button").addeventlistener("click", function (evt) { this.queryselector("svg > path:nth-of-type(1)").classlist.toggle("invisible"); this.queryselector("svg > path:nth-of-type(2)").classlist.toggle("invisible"); }); specifications specification status comment css level 2 (revision 1)the definition of 'visibility' in that specification.
<script> - SVG: Scalable Vector Graphics
WebSVGElementscript
while svg's script element is equivalent to the html <script> element, it has some discrepancies, like it uses the href attribute instead of src and it doesn't support ecmascript modules so far (see browser compatibility below for details) html,body,svg { height:100% } <svg viewbox="0 0 10 10" xmlns="http://www.w3.org/2000/svg"> <script> // <![cdata[ window.addeventlistener('domcontentloaded', () => { function getcolor () { const r = math.round(math.random() * 255).tostring(16).padstart(2,'0') const g = math.round(math.random() * 255).tostring(16).padstart(2,'0') const b = math.round(math.random() * 255).tostring(16).padstart(2,'0') return `#${r}${g}${b}` } document.queryselector('circle').addeventlistener('click', (e) => { ...
SVG documentation index - SVG: Scalable Vector Graphics
WebSVGIndex
379 scripting graphics, svg, scripting, default, eventlisteners, preventing, setproperty one can override default browser behaviors with the evt.preventdefault( ) method, add eventlisteners to objects with the syntax element.addeventlistener(event, function, usecapture), and set element properties with syntax svgelement.style.setproperty("fill-opacity", "0.0", "").
Types of attacks - Web security
ndpoints that require a post request, it's possible to programmatically trigger a <form> submit (perhaps in an invisible <iframe>) when the page is loaded: <form action="https://bank.example.com/withdraw" method="post"> <input type="hidden" name="account" value="bob"> <input type="hidden" name="amount" value="1000000"> <input type="hidden" name="for" value="mallory"> </form> <script>window.addeventlistener('domcontentloaded', (e) => { document.queryselector('form').submit(); }</script> there are a few techniques that should be used to prevent this from happening: get endpoints should be idempotent—actions that enact a change and do not simply retrieve data should require sending a post (or other http method) request.
Using custom elements - Web Components
class customelement extends htmlelement { constructor(...args) { const self = super(...args); // self functionality written in here // self.addeventlistener(...) // return the right context return self; } } if you don't need to perform any operation in the constructor, you can simply omit it so that its native behavior (see following) will be preserved.
Using the Mozilla JavaScript interface to XSL Transformations - XSLT: Extensible Stylesheet Language Transformations
var testtransform = document.implementation.createdocument("", "test", null); // just an example to get a transform into a script as a dom // xmldocument.load is asynchronous, so all processing happens in the // onload handler testtransform.addeventlistener("load", onload, false); testtransform.load("test-transform.xml"); function onload() { processor.importstylesheet(testtransform); } xsltprocessor.importstylesheet() requires one argument, a dom node.
Compiling a New C/C++ Module to WebAssembly - WebAssembly
<button class="mybutton">run myfunction</button> now add the following code at the end of the first <script> element: document.queryselector('.mybutton') .addeventlistener('click', function() { alert('check console'); var result = module.ccall( 'myfunction', // name of c function null, // return type null, // argument types null // arguments ); }); this illustrates how ccall() is used to call the exported function.