Flutter 监听页面跳转实现类似android的onResume onPause,ios的viewWillDisappear viewDidDisappear

一.监听路由事件

参考链接:How to check when my widget screen comes to visibility in flutter like onResume in Android - Stack Overflow

1.创建一个全局的路由监听

///默认全局路由观测者
final RouteObserver routeObserver = RouteObserver();

2.在App注册这个路由监听

MaterialApp(
  ...
        navigatorObservers:[routeObserver],
  ...   
      )

3.在需要监听的地方混入 RouteAware

with RouteAware

在didChangeDependencies订阅消息

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    routeObserver.subscribe(this, ModalRoute.of(context) as PageRoute);
  }

dispose释放订阅

  @override
  void dispose() {
    routeObserver.unsubscribe(this);
    super.dispose();
  }

4.重写RouteAware的方法

  @override
  void dispose() {
    routeObserver.unsubscribe(this);
    super.dispose();
  }

  @override
  void didPop() {
    super.didPop();
  }

  ///从别的页面返回 类似android的onResume ios的viewWillDisappear
  @override
  void didPopNext() {
    super.didPopNext();
  }
  
  ///首次进入 类似android的onStart
  @override
  void didPush() {
    super.didPush();
  }

  ///打开了别的页面 类似android的onPause ios的viewDidDisappear
  @override
  void didPushNext() {
    super.didPushNext();
  }

 其它:

A页面设置了监听,跳转到B页面.B页面在打开关闭C页面.A页面不会触发监听.

只监听了路由跳转事件,app缩小到桌面,重新打开还不支持

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二.监听app生命周期

参考文档:Flutter使用didChangeAppLifecycleState遇到的问题 - 简书

1.混入 WidgetsBindingObserver

with WidgetsBindingObserver

2.在initState 中添加监听

WidgetsBinding.instance.addObserver(this);

3.在dispose移除监听 

WidgetsBinding.instance.removeObserver(this);

4.重写didChangeAppLifecycleState

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) async {
    print('\n\ndidChangeAppLifecycleState');
    switch (state) {
      case AppLifecycleState.resumed:
        print('\n\nresumed');
        _mymethod();
        break;
      case AppLifecycleState.inactive:
        print('\n\ninactive');
        break;
      case AppLifecycleState.paused:
        print('\n\npaused');
        break;
      case AppLifecycleState.detached:
        print('\n\ndetached');
        break;
    }
  }

---

以上两个方法结合使用即可实现完整的页面隐藏,显示回调

例如:

标记当前页面

//由子页面 返回时刷新
  @override
  void didPopNext() {
    _inCurrentPage = true;
    //TODO 这里做 onResume  方法

     refreshPage();

  }

  //进入子页面
  @override
  void didPushNext() {
    _inCurrentPage = false;
    super.didPushNext();
  }

//由后台返回主屏幕 刷新数据
  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    super.didChangeAppLifecycleState(state);
    if (state == AppLifecycleState.resumed && _inCurrentPage) {
      //TODO 这里做 onResume  方法

      refreshPage();
    }
  }