详解flutter如何实现局部导航管理

///工具类：用于局部导航管理
class LocalNavigator extends StatelessWidget {
  final Widget child;
  const LocalNavigator(this.child, {Key? key}) : super(key: key);
  @override
  Widget build(BuildContext context) {
    return Navigator(
      initialRoute: '/',
      onGenerateRoute: (settings) {
        return MaterialPageRoute(
          settings: const RouteSettings(name: '/'),
          builder: (context) {
            return child;
          },
        );
      },
    );
  }
}

/// 通过局部导航开启一个弹窗
  static Future<T?> showLocalDialog<T>(
    BuildContext context,
    Widget child,
  ) {
    return showDialog<T?>(
      context: context,
      builder: (context) {
        return Dialog(
          child: SizedBox(
            width: 200,
            height: 300,
            child: LocalNavigator(child),
          ),
        );
      },
    );
  }

void main() {
  runApp(const Material(
    child: MyApp(),
  ));
}
class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('demo'),
        ),
        body: StatefulBuilder(
          builder: (context, setState) {
            return Center(
              child: TextButton(
                child: const Text('打开弹窗'),
                onPressed: () {
                 showLocalDialog<String?>(context, const _PageA())
                      .then(
                    (data) {
                      //接收来自 dialog 的回调数据
                      if (data != null) {
                        Fluttertoast.showToast(msg: 'mainPage 接收数据：$data');
                      }
                    },
                  );
                },
              ),
            );
          },
        ),
      ),
    );
  }
}
class _PageA extends StatelessWidget {
  const _PageA({Key? key}) : super(key: key);
  void jumpPageB(BuildContext context) {
    Navigator.push<String?>(
      context,
      MaterialPageRoute(
        builder: (context) => const _PageB(),
      ),
    ).then(
      (data) {
        if (data != null) {
          //接收来自 pageB 的回调数据
          Fluttertoast.showToast(msg: 'pageA 接收数据：$data');
        }
      },
    );
  }
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('PageA')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            TextButton(
              onPressed: () {
                jumpPageB(context);
              },
              child: const Text('跳转页面B'),
            ),
          ],
        ),
      ),
    );
  }
}
class _PageB extends StatelessWidget {
  const _PageB({Key? key}) : super(key: key);
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('PageB')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            TextButton(
              onPressed: () {
                Navigator.of(context).pop('我是来自pageB的数据');
              },
              child: const Text('返回pageA'),
            ),
            const SizedBox(height: 20),
            TextButton(
              onPressed: () {
                Navigator.of(context, rootNavigator: true).pop('我是来自pageC的数据');
              },
              child: const Text('关闭整个弹窗'),
            ),
          ],
        ),
      ),
    );
  }
}

Navigator.push<String?>(
      context,
      MaterialPageRoute(
        builder: (context) => const _PageB(),
      ),
    ).then(
      (data) {
        if (data != null) {
          //接收来自 pageB 的回调数据
          Fluttertoast.showToast(msg: 'pageA 接收数据：$data');
        }
      },
    );