AudioTrackList.onremovetrack

The AudioTrackList onremovetrack event handler is called when the removetrack event occurs, indicating that an audio track has been removed from the media element, and therefore also from the AudioTrackList.

The event is passed into the event handler in the form of a TrackEvent object, whose track property identifies the track that was removed from the media element's AudioTrackList.

AudioTrackList.onremovetrack = eventHandler;

Set onremovetrack to a function that accepts as input a TrackEvent object which indicates in its track property which audio track has been removed from the media element.

This simple example just fetches the current number of audio tracks in the media element whenever a track is removed from the media element.

document.querySelector("my-video").audioTracks.onremovetrack = function(event) {
  myTrackCount = document.querySelector("my-video").audioTracks.length;
};

The current number of audio tracks remaining in the media element is obtained from AudioTrackList property length.