flutter 检测生命周期 进行相关操作

@override
void initState() {
  super.initState();
//注册
  WidgetsBinding.instance.addObserver(this);

}

@override
void dispose() {
  super.dispose();
//注销 
  WidgetsBinding.instance.removeObserver(this);
 
}
//主要检测生命周期 
@override
void didChangeAppLifecycleState(AppLifecycleState state) {
  //每次唤醒进行检查挨app更新
  if (state == AppLifecycleState.resumed) {
    checkAppVersion();
  }
}

 

class FlutterLifeCycleState extends State
    with WidgetsBindingObserver {
  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this); //添加观察者
  }

  ///生命周期变化时回调
//  resumed:应用可见并可响应用户操作
//  inactive:用户可见，但不可响应用户操作
//  paused:已经暂停了，用户不可见、不可操作
//  suspending：应用被挂起，此状态IOS永远不会回调
  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    super.didChangeAppLifecycleState(state);
    print("@@@@@@@@@  didChangeAppLifecycleState: $state");
   //每次唤醒进行检查更新
    if (state == AppLifecycleState.resumed) {
      checkAppVersion();
    }
  }

  ///当前系统改变了一些访问性活动的回调
  @override
  void didChangeAccessibilityFeatures() {
    super.didChangeAccessibilityFeatures();
    print("@@@@@@@@@ didChangeAccessibilityFeatures");
  }

  /// Called when the system is running low on memory.
  ///低内存回调
  @override
  void didHaveMemoryPressure() {
    super.didHaveMemoryPressure();
    print("@@@@@@@@@ didHaveMemoryPressure");
  }

  /// Called when the system tells the app that the user's locale has
  /// changed. For example, if the user changes the system language
  /// settings.
  ///用户本地设置变化时调用，如系统语言改变
  @override
  void didChangeLocales(List locale) {
    super.didChangeLocales(locale);
    print("@@@@@@@@@ didChangeLocales");
  }

  /// Called when the application's dimensions change. For example,
  /// when a phone is rotated.
  ///应用尺寸改变时回调，例如旋转
  @override
  void didChangeMetrics() {
    super.didChangeMetrics();
    Size size = WidgetsBinding.instance.window.physicalSize;
    print("@@@@@@@@@ didChangeMetrics  ：宽：${size.width} 高：${size.height}");
  }

  /// {@macro on_platform_brightness_change}
  @override
  void didChangePlatformBrightness() {
    super.didChangePlatformBrightness();
    print("@@@@@@@@@ didChangePlatformBrightness");
  }

  ///文字系数变化
  @override
  void didChangeTextScaleFactor() {
    super.didChangeTextScaleFactor();
    print(
        "@@@@@@@@@ didChangeTextScaleFactor  ：${WidgetsBinding.instance.window.textScaleFactor}");
  }

  @override
  Widget build(BuildContext context) {
    return Container(
      child: Center(
        child: Text("flutter"),
      ),
    );
  }

  @override
  void dispose() {
    super.dispose();
    WidgetsBinding.instance.removeObserver(this); //销毁观察者
  }
}