MediaStream.active

The active read-only property of the MediaStream interface returns a Boolean value which is true if the stream is currently active; otherwise, it returns false. A stream is considered active if at least one of its MediaStreamTracks is not in the MediaStreamTrack.ended state. Once every track has ended, the stream's active property becomes false.

A Boolean value which is true if the stream is currently active; otherwise, the value is false.

In this example, a new stream whose source is the user's local camera and microphone is requested using getUserMedia(). When that stream becomes available (that is, when the returned Promise is fulfilled, a button on the page is updated based on whether or not the stream is currently active.

const promise = navigator.mediaDevices.getUserMedia({
  audio: true,
  video: true
});

promise.then((stream) => {
  const startBtn = document.querySelector('#startBtn');
  startBtn.disabled = stream.active;
});