TextTrackList: addtrack event

Syntax

Use the event name in addEventListener():

js

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

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

js

onaddtrack = (event) => { }

Event type

A TrackEvent. Inherits from Event.

Examples

Using addEventListener():

js

const mediaElement = document.querySelector("video, audio");

mediaElement.textTracks.addEventListener("addtrack", (event) => {
  console.log(`Text track: ${event.track.label} added`);
});

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

js

const mediaElement = document.querySelector("video, audio");

mediaElement.textTracks.onaddtrack = (event) => {
  console.log(`Text track: ${event.track.label} added`);
};