XRSystem: devicechange event

A devicechange event is fired on an XRSystem object whenever the whenever the availability of immersive XR devices has changed; for example, a VR headset or AR goggles have been connected or disconnected. It's a generic Event with no added properties.

Note: Not to be confused with the MediaDevices devicechange event.

Bubbles No
Cancelable No
Interface Event
Event handler XRSystem.ondevicechange

Usage notes

devicechange events are not delivered if the document which owns the XRSystem object has been granted permission to do so through the xr-spatial-tracking feature policy.

You can use this event to, for example, monitor for the availability of a WebXR-compatible device so that you can enable a UI element which the user can use to activate immersive mode. This is shown in the example below.

Example

The example shown here handles the devicechange event by toggling the availability of the "Enter XR" button based on whether or not any immersive devices are currently available.

if (navigator.xr) {
  navigator.xr.addEventListener("devicechange", event => {
    navigator.xr.isSessionSupported("immersive-vr")
    .then(immersiveOK) => {
      if (immersiveOK) {
        enableXRButton.disabled = false;
      } else {
        enableXRButton.disabled = true;
      }
    });
  });
}

When devicechange is received, the handler set up in this code calls the XR method isSessionSupported() to find out if there's a device available that can handle immersive VR presentations. If there is, the button to enter XR mode is enabled; otherwise it's disabled.

You can also use the ondevicechange event handler property to set a single handler for devicechange events:

if (navigator.xr) {
  navigator.xr.ondevicechange = event => {
    /* ... etc ... */
  };
}

Specifications

Specification Status Comment
WebXR Device API
The definition of 'devicechange event' in that specification.
Working Draft Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
devicechange event
Experimental
Chrome Full support 79Edge Full support 79Firefox No support NoIE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android Full support 79Firefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android Full support 11.2

Legend

Full support  
Full support
No support  
No support
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.

See also