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()
.
AudioTrackList.onchange = eventHandler;
Set onchange
to a function that should be called whenever tracks are enabled or disabled on the media element.
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.
Specification |
---|
HTML Standard (HTML) # handler-tracklist-onchange |
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
onchange |
37 |
79
12-79
|
33 |
10 |
24 |
7 |
No |
37 |
33 |
24 |
7 |
No |
© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/AudioTrackList/onchange