Flutter 如何监听App页面是否隐藏

使用AppLifecycleListener 来监听 想在那个页面监听就在那个页面初始化 别忘记还有销毁

class _HomePageState extends State<HomePage> with WidgetsBindingObserver {

  @override
  void initState() {
    super.initState();

    WidgetsFlutterBinding.ensureInitialized(); // 确保初始化Flutter的绑定
    WidgetsBinding.instance!.addObserver(this); // 添加观察者
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    // 在这里处理生命周期事件
    switch (state) {
      case AppLifecycleState.inactive:
        print('App is inactive');
        break;
      case AppLifecycleState.resumed://进入前台
        print('App is resumed');
        break;
      case AppLifecycleState.paused://进入后台
        print('App is paused');
        break;
      case AppLifecycleState.detached:
        print('App is suspending');
        break;
      case AppLifecycleState.hidden:
        // TODO: Handle this case.
        throw UnimplementedError();
    }
  }
@override
void dispose() {
  WidgetsBinding.instance!.removeObserver(lifecycleHandler); // 移除观察者
  super.dispose();
}
}