onPushSubscriptionChange property
An event handler fired whenever a pushsubscriptionchange event occurs — when a push subscription has been invalidated, or is about to be invalidated (e.g. when a push service sets an expiration time).
Implementation
Stream<PushEvent> get onPushSubscriptionChange =>
_onPushSubscriptionChange ??=
callbackToStream(_delegate, 'onpushsubscriptionchange', PushEvent._);