VideoTrackList: addtrack event

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

Syntax

Use the event name in addEventListener():

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

Alternatively, assign to the event handler property of the interface:

onaddtrack = (event) => { }

Event type

A TrackEvent. Inherits from Event.

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 (but note that this replaces other event listeners added using onaddtrack, if any):

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

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