MediaStream: addtrack event

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.

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

addEventListener('addtrack', event => { });

onaddtrack = event => { };

An MediaStreamTrackEvent. Inherits from Event.

Also inherits properties from its parent interface, Event.

track Read only

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

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`);
};

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