dispose method
Widget 被销毁时,通常会在此方法中移除监听或清理数据等,整个生命周期只会执行一次
Implementation
@override
void dispose() {
_dispatchLifecycleState(LifecycleState.onDestroy);
///WidgetsBindingObserver 注销
WidgetsBinding.instance.removeObserver(this);
///解绑
LifecycleRouteObserver.routeObserver.unsubscribe(this);
}