VideoTrackList: addtrack event

The addtrack event is fired when a video track is added to a VideoTrackList.

Syntax

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

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

onaddtrack = (event) => { }

Event type

A TrackEvent. Inherits from Event.

Event properties

In addition to the properties listed below, properties from the parent interface, Event, are available.

track Read only

The newly-added VideoTrack the event is in reference to.

Examples

Using addEventListener():

const videoElement = document.querySelector("video");

videoElement.videoTracks.addEventListener("addtrack", (event) => {
  console.log(`Video track: ${event.track.label} added`);
});

Using the onaddtrack event handler property:

const videoElement = document.querySelector("video");

videoElement.videoTracks.onaddtrack = (event) => {
  console.log(`Video track: ${event.track.label} added`);
};

Specifications

Browser compatibility

See also

• Related events: removetrack, change
• This event on AudioTrackList targets: addtrack
• This event on MediaStream targets: addtrack
• Media Capture and Streams API
• WebRTC