This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The onvoiceschanged
property of the SpeechSynthesis
interface represents an event handler that will run when the list of SpeechSynthesisVoice
objects that would be returned by the SpeechSynthesis.getVoices()
method has changed (when the voiceschanged event fires.)
This may occur when speech synthesis is being done on the server-side and the voices list is being determined asynchronously, or when client-side voices are installed/uninstalled while a speech synthesis application is running.
Syntax
speechSynthesisInstance.onvoiceschanged = function() { ... };
Examples
This could be used to populate a list of voices that the user can choose between when the event fires (see our Speak easy synthesis demo.) Note that Firefox doesn't support it at present, and will just return a list of voices when SpeechSynthesis.getVoices()
is fired. With Chrome however, you have to wait for the event to fire before populating the list, hence the bottom if statement seen below.
var voices = []; function populateVoiceList() { voices = synth.getVoices(); for(i = 0; i < voices.length ; i++) { var option = document.createElement('option'); option.textContent = voices[i].name + ' (' + voices[i].lang + ')'; if(voices[i].default) { option.textContent += ' -- DEFAULT'; } option.setAttribute('data-lang', voices[i].lang); option.setAttribute('data-name', voices[i].name); voiceSelect.appendChild(option); } } populateVoiceList(); if (speechSynthesis.onvoiceschanged !== undefined) { speechSynthesis.onvoiceschanged = populateVoiceList; }
Specifications
Specification | Status | Comment |
---|---|---|
Web Speech API The definition of 'onvoiceschanged' in that specification. |
Draft |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
onvoiceschanged | Chrome Full support 33 | Edge Full support 14 | Firefox Full support 49 | IE No support No | Opera No support No | Safari No support No | WebView Android Full support 4.4.3 | Chrome Android Full support 33 | Firefox Android
Full support
62
| Opera Android No support No | Safari iOS No support No | Samsung Internet Android Full support 3.0 |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- User must explicitly enable this feature.
- User must explicitly enable this feature.