在StatelessWidget中使用AppLifecycleState

import 'package:flutter/material.dart';

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with WidgetsBindingObserver {
  AppLifecycleState _appLifecycleState;

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

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    setState(() {
      _appLifecycleState = state;
    });

    // 在这里可以根据不同的生命周期状态执行相应的操作
    switch (state) {
      case AppLifecycleState.resumed:
        // 应用程序进入活动状态
        break;
      case AppLifecycleState.inactive:
        // 应用程序进入非活动状态
        break;
      case AppLifecycleState.paused:
        // 应用程序进入后台暂停状态
        break;
      case AppLifecycleState.detached:
        // 应用程序被销毁
        break;
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('App Lifecycle State'),
      ),
      body: Center(
        child: Text('Current State: $_appLifecycleState'),
      ),
    );
  }
}

void main() {
  runApp(MyApp());
}