The AudioTrackList
property onchange
is an event handler which is called when the change
event occurs, indicating that one or more of the AudioTrack
s in the AudioTrackList
have been enabled or disabled.
The event is passed into the event handler in the form of an Event
object; the event doesn't provide any additional information. To determine the new state of media's tracks, you'll have to look at their AudioTrack.enabled
flags.
Note: You can also add a handler for the change
event using addEventListener()
.
Syntax
AudioTrackList.onchange = eventHandler;
Value
Set onchange
to a function that should be called whenever tracks are enabled or disabled on the media element.
Example
This snippet establishes a handler for the change
event that looks at each of the tracks in the list, calling a function to update the state of a user interface control that indicates the current state of the track.
var trackList = document.querySelector("video").audioTracks; trackList.onchange = function(event) { trackList.forEach(function(track) { updateTrackEnabledButton(track.id, track.enabled); }); };
The updateTrackEnabledButton()
, in this example, should be a function that finds a user interface control using the track's id
(perhaps the app uses the track ID as the control element's ID) and the track's enabled
flag to determine which state the control should be in now.
Specifications
Specification | Status | Comment |
---|---|---|
HTML Living Standard The definition of 'AudioTrackList.onchange' in that specification. |
Living Standard | |
HTML5 The definition of 'AudioTrackList.onchange' in that specification. |
Recommendation |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
onchange | Chrome
Full support
45
| Edge
Full support
79
| Firefox
Full support
33
| IE Full support 10 | Opera
Full support
32
| Safari Full support 6.1 | WebView Android Full support 45 | Chrome Android
Full support
45
| Firefox Android
Full support
33
| Opera Android
Full support
32
| Safari iOS Full support 7 | Samsung Internet Android No support No |
Legend
- Full support
- Full support
- No support
- No support
- User must explicitly enable this feature.
- User must explicitly enable this feature.