active

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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.

Syntax

var isActive = MediaStream.active;

Value

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

Example

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.

var promise = navigator.mediaDevices.getUserMedia({
  audio: true,
  video: true
});
promise.then(function(stream) {
  var startBtn = document.querySelector('#startBtn');
  startBtn.disabled = stream.active;
};)

Specifications

Specification Status Comment
Media Capture and Streams
The definition of 'active' in that specification.
Editor's Draft Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Microsoft Edge Internet Explorer Opera Safari (WebKit)
Basic support (Yes) 52 (52) ? ? ? ?
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support (Yes) 52.0 (52) ? ? ? ? (Yes)

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