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web api interface

XRSessionEvent

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Secure context

The WebXR Device API’s XRSessionEvent interface describes an event which indicates the change of the state of an XRSession. These events occur, for example, when the session ends or the visibility of its context changes.

Constructor

Instance properties

In addition to properties inherited from its parent interface, Event, XRSessionEvent provides the following:

Instance methods

While XRSessionEvent defines no methods, it inherits methods from its parent interface, Event.

Session event types

The following events are represented using the XRSessionEvent interface, and are permitted values for its type property.

  • end
    • : Fired at the session when it has ended, after being terminated by the application or the user agent.
  • visibilitychange
    • : Fired at the session whenever its visibility state changes.

Examples

This example creates a listener that watches for the visibility state of the session to change. It reacts by calling a function mySessionVisible() with a Boolean indicating whether or not the session is visible; this function might, for instance, spin up or reconfigure a worker that handles rendering the scene.

xrSession.addEventListener("visibilitychange", (e) => {
  switch (e.session.visibilityState) {
    case "visible":
    case "visible-blurred":
      mySessionVisible(true);
      break;
    case "hidden":
      mySessionVisible(false);
      break;
  }
});

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.