Flutter开发之——监听堆栈变化，2024我的Android大厂面试之旅

在Flutter中，你可以使用Navigator的overrides属性来监听路由堆栈的变化。以下是一个简单的示例，展示如何在Flutter应用中监听路由堆栈的变化：

import 'package:flutter/material.dart';
 
void main() {
  runApp(MyApp());
}
 
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: HomePage(),
      navigatorObservers: [MyNavigatorObserver()],
    );
  }
}
 
class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: TextButton(
          child: Text('Go to Details Page'),
          onPressed: () {
            Navigator.push(context, MaterialPageRoute(builder: (context) => DetailsPage()));
          },
        ),
      ),
    );
  }
}
 
class DetailsPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Details Page')),
      body: Center(
        child: TextButton(
          child: Text('Go back'),
          onPressed: () {
            Navigator.pop(context);
          },
        ),
      ),
    );
  }
}
 
class MyNavigatorObserver extends NavigatorObserver {
  @override
  void didPush(Route route, Route previousRoute) {
    print('Did push route: $route');
  }
 
  @override
  void didPop(Route route, Route previousRoute) {
    print('Did pop route: $route');
  }
 
  @override
  void didRemove(Route route, Route previousRoute) {
    print('Did remove route: $route');
  }
 
  @override
  void didStartUserGesture(Route route, Route previousRoute) {
    print('Did start user gesture on route: $route');
  }
 
  @override
  void didStopUserGesture() {
    print('Did stop user gesture');
  }
}

在这个示例中，我们定义了一个MyNavigatorObserver类，它扩展了NavigatorObserver并覆盖了相关的方法来监听路由堆栈的变化。然后，我们将这个观察者添加到了MaterialApp的navigatorObservers属性中。当用户进行页面导航时，相关的方法会被调用，并打印出相关的路由信息。