setBackgroundKeepAlive method

@override Future<void> setBackgroundKeepAlive(bool enabled)

Opts the session into an Android background keep-alive (wake + Wi-Fi locks) for off-device playback such as casting. Android only; defaults to a no-op so other platforms (and any that do not override it) are safe.

Implementation

@override
Future<void> setBackgroundKeepAlive(bool enabled) async {
  // Best-effort only: the Screen Wake Lock API keeps the screen awake while
  // the page is visible — it does NOT keep a backgrounded tab's CPU/network
  // alive (background tabs are throttled regardless). There is no real
  // background keep-alive primitive on the web platform.
  try {
    final navigator = web.window.navigator as JSObject;
    final wakeLock = navigator.getProperty<JSObject?>('wakeLock'.toJS);
    if (wakeLock == null) return; // Unsupported browser.
    if (enabled) {
      if (_wakeLockSentinel != null) return;
      final promise =
          wakeLock.callMethod<JSPromise>('request'.toJS, 'screen'.toJS);
      _wakeLockSentinel = (await promise.toDart) as JSObject?;
    } else {
      final sentinel = _wakeLockSentinel;
      _wakeLockSentinel = null;
      if (sentinel != null) {
        await sentinel.callMethod<JSPromise>('release'.toJS).toDart;
      }
    }
  } catch (e) {
    // Wake Lock unavailable or rejected (e.g. requires user activation). Ignore.
  }
}