authentication - 如何在Bloc Login Flutter中使用带有身份验证的抽屉导航中的路线

Question

我实现了Flutter Bloc Login示例，就像指南页面here一样:

接下来，我在页面上添加了NavigationDrawer。

但是我不知道如何在页面之间导航，我尝试了普通的 Navigator.push ，但没有用，并且我在MaterialApp中使用了路由，但不幸的是，这种方式没有用。

main.dart

void main() {
  BlocSupervisor.delegate = SimpleBlocDelegate();
  final userRepository = UserRepository();
  runApp(
    BlocProvider<AuthenticationBloc>(
      create: (context) {
        return AuthenticationBloc(userRepository: userRepository)
          ..add(AppStarted());
      },
      child: App(userRepository: userRepository),
    ),
  );
}

class App extends StatelessWidget {
  final UserRepository userRepository;
  App({Key key, @required this.userRepository}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: BlocBuilder<AuthenticationBloc, AuthenticationState>(
        builder: (context, state) {
          if (state is AuthenticationAuthenticated) {
            //return Counter();
            //return ListPage();
            return ProfilePage();
          }
          if (state is AuthenticationUnauthenticated) {
            return LoginPage(userRepository: userRepository);
          }
          if (state is AuthenticationLoading) {
            return LoadingIndicator();
          }
          return SplashPage();
        },
      ),
      initialRoute: '/',
      routes: {
        '/': (context) => SplashPage(),
        '/counter': (context) => Counter(),
        '/profile': (context) => ProfilePage(),
        '/list': (context) => ListPage(),
      },
    );
  }
}

navigation_drawer.dart

  Widget build(BuildContext context) {
    return Drawer(
      child: ListView(
        // Important: Remove any padding from the ListView.
        padding: EdgeInsets.zero,
        children: <Widget>[
          Container(...),
          ListTile(
            title: Text('Profile'),
            onTap: () {
              /* TODO: check token is not null */
              Navigator.pushNamed(context, '/profile');

              },
          ),
          ListTile(
            title: Text('Counter'),
            onTap: () {
              Navigator.pushNamed(context, '/counter');
            },
          ),
          ListTile(
            title: Text('My List'),
            onTap: () {
              Navigator.pushNamed(context, '/list');
            },
          ),
        ],
      ),
    );
  }

Answer 1

很简单，您忘记使用支架小部件作为的子代。如下所示:
main.dart

void main() {
 BlocSupervisor.delegate = SimpleBlocDelegate();
 final userRepository = UserRepository();
 runApp(
 BlocProvider<AuthenticationBloc>(
 create: (context) {
 return AuthenticationBloc(userRepository: userRepository)
 ..add(AppStarted());
 },
 child: App(userRepository: userRepository),
 ),
 );
}

class App extends StatelessWidget {
 final UserRepository userRepository;
 App({Key key, @required this.userRepository}) : super(key: key);

 @override
 Widget build(BuildContext context) {
 return MaterialApp(
 debugShowCheckedModeBanner: false,
 home: Scaffold(
 drawer: build(context),
 body: BlocBuilder<AuthenticationBloc, AuthenticationState>(
 builder: (context, state) {
 if (state is AuthenticationAuthenticated) {
 //return Counter();
 //return ListPage();
 return ProfilePage();
 }
 if (state is AuthenticationUnauthenticated) {
 return LoginPage(userRepository: userRepository);
 }
 if (state is AuthenticationLoading) {
 return LoadingIndicator();
 }
 return SplashPage();
 },
 ),
 ),
 initialRoute: '/',
 routes: {
 '/': (context) => SplashPage(),
 '/counter': (context) => Counter(),
 '/profile': (context) => ProfilePage(),
 '/list': (context) => ListPage(),
 },
 );
 }
}

navigation_drawer.dart

Widget build(BuildContext context) {
  return Drawer(
    child: ListView(
      // Important: Remove any padding from the ListView.
      padding: EdgeInsets.zero,
      children: <Widget>[
        Container(...),
        ListTile(
          title: Text('Profile'),
          onTap: () {
            /* TODO: check token is not null */
            Navigator.pushNamed(context, '/profile');

          },
        ),
        ListTile(
          title: Text('Counter'),
          onTap: () {
            Navigator.pushNamed(context, '/counter');
          },
        ),
        ListTile(
          title: Text('My List'),
          onTap: () {
            Navigator.pushNamed(context, '/list');
          },
        ),
      ],
    ),
  );
}

但我不建议您以这种方式与集团合作。