MediaStream: addtrack event

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2017.

The addtrack event is fired when a new MediaStreamTrack object has been added to a MediaStream.

This event is not cancelable and does not bubble.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

js
addEventListener("addtrack", (event) => { })

onaddtrack = (event) => { }

Event type

A MediaStreamTrackEvent. Inherits from Event.

Event MediaStreamTrackEvent

Event properties

Also inherits properties from its parent interface, Event.

MediaStreamTrackEvent.track Read only

A MediaStreamTrack object representing the track which was added to the stream.

Examples

Using addEventListener():

js
const stream = new MediaStream();

stream.addEventListener("addtrack", (event) => {
  console.log(`New ${event.track.kind} track added`);
});

Using the onaddtrack event handler property:

js
const stream = new MediaStream();

stream.onaddtrack = (event) => {
  console.log(`New ${event.track.kind} track added`);
};

Specifications

Specification
Media Capture and Streams
# event-mediastream-addtrack

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
addtrack event
Chrome – Full support
Chrome 26 (Release date: 2013-03-26)
footnote Full support
Edge – Full support
Edge 12 (Release date: 2015-07-29)
footnote Full support
Firefox – Full support
Firefox 50 (Release date: 2016-11-15)
footnote Full support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Full support
Safari 11 (Release date: 2017-09-19)
footnote Full support
Chrome Android – Full support
Chrome Android 26 (Release date: 2013-04-03)
footnote Full support
Firefox for Android – Full support
Firefox for Android 50 (Release date: 2016-11-15)
footnote Full support
Opera Android – Full support
Opera Android 14 (Release date: 2013-05-21)
footnote Full support
Safari on iOS – Full support
Safari on iOS 11 (Release date: 2017-09-19)
footnote Full support
Samsung Internet – Full support
Samsung Internet 1.5 (Release date: 2013-09-25)
footnote Full support
WebView Android – Full support
WebView Android 4.4 (Release date: 2013-12-09)
footnote Full support
WebView on iOS – Full support
WebView on iOS 11 (Release date: 2017-09-19)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

See also