Web/API/MediaStream/addtrack event

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

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.	Candidate Recommendation

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
addtrack event	Chrome Full support Yes	Edge Full support 12	Firefox Full support 50	IE No support No	Opera No support No	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 50	Opera Android No support No	Safari iOS Full support Yes	Samsung Internet Android Full support Yes

Legend

Full support  

Full support

No support  

No support

See also

• Related events: removetrack
• This event on AudioTrackList targets: addtrack
• This event on VideoTrackList targets: addtrack
• Media Streams API
• WebRTC

MediaStream: addtrack event by Mozilla Contributors is licensed under CC-BY-SA 2.5.