Bloc: Flutter login example with drawer, BlocBuilder not triggered after state change

Created on 4 Mar 2019  ·  22Comments  ·  Source: felangel/bloc

I took your login example and tried to play with it a little and I added a drawer with some entriues and a logout button at the bottom of it.

This is the drawer code:

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_login/authentication/authentication.dart';

class AppDrawer extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final AuthenticationBloc authenticationBloc =
        BlocProvider.of<AuthenticationBloc>(context);

    return Drawer(
      child: Column(
        children: <Widget>[
          MediaQuery.removePadding(
            context: context,
            removeTop: true,
            child: Expanded(
              child: ListView(
                padding: const EdgeInsets.only(top: 8.0),
                children: <Widget>[
                  ListTile(
                    leading: Icon(Icons.group),
                    title: Text("Page 1"),
                    onTap: () {
                      Navigator.pushReplacementNamed(context, '/page1');
                    },
                  ),
                  ListTile(
                    leading: Icon(Icons.group),
                    title: Text("Home"),
                    onTap: () {
                      Navigator.pushReplacementNamed(context, '/');
                    },
                  ),
                  ListTile(
                    leading: Icon(Icons.exit_to_app),
                    title: Text('Logout'),
                    onTap: () {
                      Navigator.pop(context);
                      authenticationBloc.dispatch(LoggedOut());
                    },
                  )
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }
}

then I created a new page page1.dart:

import 'package:flutter/material.dart';
import 'package:flutter_login/app_drawer.dart';

class Page1 extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Page1'),
      ),
      drawer: AppDrawer(),
      body: Text('Hi there'),
    );
  }
}

and finally I updated the home_page.dart to add the drawer:

import 'package:flutter/material.dart';

import 'package:flutter_bloc/flutter_bloc.dart';

import 'package:flutter_login/authentication/authentication.dart';
import 'package:flutter_login/app_drawer.dart';

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final AuthenticationBloc authenticationBloc =
        BlocProvider.of<AuthenticationBloc>(context);

    return Scaffold(
      appBar: AppBar(
        title: Text('Home'),
      ),
      drawer: AppDrawer(),
      body: Container(
        child: Center(
            child: RaisedButton(
          child: Text('logout'),
          onPressed: () {
            authenticationBloc.dispatch(LoggedOut());
          },
        )),
      ),
    );
  }
}

main.dart:

import 'package:flutter/material.dart';

import 'package:bloc/bloc.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:user_repository/user_repository.dart';

import 'package:flutter_login/authentication/authentication.dart';
import 'package:flutter_login/splash/splash.dart';
import 'package:flutter_login/login/login.dart';
import 'package:flutter_login/home/home.dart';
import 'package:flutter_login/common/common.dart';

import 'package:flutter_login/page1.dart';

class SimpleBlocDelegate extends BlocDelegate {
  @override
  void onTransition(Transition transition) {
    print(transition);
  }

  @override
  void onError(Object error, StackTrace stacktrace) {
    print(error);
  }
}

void main() {
  BlocSupervisor().delegate = SimpleBlocDelegate();
  runApp(App(userRepository: UserRepository()));
}

class App extends StatefulWidget {
  final UserRepository userRepository;

  App({Key key, @required this.userRepository}) : super(key: key);

  @override
  State<App> createState() => _AppState();
}

class _AppState extends State<App> {
  AuthenticationBloc _authenticationBloc;
  UserRepository get _userRepository => widget.userRepository;

  @override
  void initState() {
    _authenticationBloc = AuthenticationBloc(userRepository: _userRepository);
    _authenticationBloc.dispatch(AppStarted());
    super.initState();
  }

  @override
  void dispose() {
    _authenticationBloc.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return BlocProvider<AuthenticationBloc>(
      bloc: _authenticationBloc,
      child: MaterialApp(
        routes: {
          '/page1': (_) => Page1(),
        },
        home: BlocBuilder<AuthenticationEvent, AuthenticationState>(
          bloc: _authenticationBloc,
          builder: (BuildContext context, AuthenticationState state) {
            if (state is AuthenticationUninitialized) {
              return SplashPage();
            }
            if (state is AuthenticationAuthenticated) {
              return HomePage();
            }
            if (state is AuthenticationUnauthenticated) {
              return LoginPage(userRepository: _userRepository);
            }
            if (state is AuthenticationLoading) {
              return LoadingIndicator();
            }
          },
        ),
      ),
    );
  }
}

When i try to logout, the bloc correctly change the state to AuthenticationUnauthenticated, but the BlocBuilder builder method is not triggered and the login page is not displayed.

flutter: Transition { currentState: LoginInitial, event: LoginButtonPressed { username: , password:  }, nextState: LoginLoading }
flutter: Transition { currentState: LoginLoading, event: LoginButtonPressed { username: , password:  }, nextState: LoginInitial }
flutter: Transition { currentState: AuthenticationUnauthenticated, event: LoggedIn { token: token }, nextState: AuthenticationLoading }
flutter: Transition { currentState: AuthenticationLoading, event: LoggedIn { token: token }, nextState: AuthenticationAuthenticated }
flutter: Transition { currentState: AuthenticationAuthenticated, event: LoggedOut, nextState: AuthenticationLoading }
flutter: Transition { currentState: AuthenticationLoading, event: LoggedOut, nextState: AuthenticationUnauthenticated }

Can you help please?
Note that you have to visite Page 1 to reproduce this issue.

bloc

question
Source
picture boukmi

Most helpful comment

@janardhanmupparaju if you push new routes onto the stack you need to pop them before you add the LoggedOut event.

Navigator.of(context).popUntil(ModalRoute.withName('/'));
// then add/dispatch LoggedOut()

Thank you @felangel , it was working. i just added that line before dispatch LoggedOut().

picture janardhanmupparaju on 12 Feb 2020
🚀1 ❤1 🎉1 😄1 👍1

All 22 comments

@boukmi thanks for opening an issue!

I think the issue you’re facing is you are disposing the widget along with BlocBuilder when you use pushReplacementNamed. I would recommend just using push and pop otherwise you destroy the underlying views in the navigation stack.

Let me know if that helps 👍

felangel picture felangel on 4 Mar 2019

@felangel thank you for your quick reply
I updated the drawer code:

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_login/authentication/authentication.dart';

import 'package:flutter_login/page1.dart';
import 'package:flutter_login/home/home.dart';

class AppDrawer extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final AuthenticationBloc authenticationBloc =
        BlocProvider.of<AuthenticationBloc>(context);

    return BlocBuilder<AuthenticationEvent, AuthenticationState>(
      bloc: authenticationBloc,
      builder: (BuildContext context, AuthenticationState state) {
        return Drawer(
          child: Column(
            children: <Widget>[
              MediaQuery.removePadding(
                context: context,
                removeTop: true,
                child: Expanded(
                  child: ListView(
                    padding: const EdgeInsets.only(top: 8.0),
                    children: <Widget>[
                      ListTile(
                        leading: Icon(Icons.group),
                        title: Text("Page 1"),
                        onTap: () {
                          Navigator.push(
                            context,
                            MaterialPageRoute(builder: (_) => Page1()),
                          );
                        },
                      ),
                      ListTile(
                        leading: Icon(Icons.group),
                        title: Text("Home"),
                        onTap: () {
                          Navigator.push(
                            context,
                            MaterialPageRoute(builder: (_) => HomePage()),
                          );
                        },
                      ),
                      ListTile(
                        leading: Icon(Icons.exit_to_app),
                        title: Text('Logout'),
                        onTap: () {
                          authenticationBloc.dispatch(LoggedOut());
                        },
                      )
                    ],
                  ),
                ),
              ),
            ],
          ),
        );
      },
    );
  }
}

Still does not work and now I'm getting this error when I click on logout button:
```
flutter: ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
flutter: The following assertion was thrown while finalizing the widget tree:
flutter: setState() or markNeedsBuild() called when widget tree was locked.
flutter: This _ModalScope widget cannot be marked as needing to build because the framework is
flutter: locked.
flutter: The widget on which setState() or markNeedsBuild() was called was:
flutter: _ModalScope-LabeledGlobalKey<_ModalScopeState>#36518
flutter:
flutter: When the exception was thrown, this was the stack:
flutter: #0 Element.markNeedsBuild.
package:flutter/…/widgets/framework.dart:3514
flutter: #1 Element.markNeedsBuild
package:flutter/…/widgets/framework.dart:3523
flutter: #2 State.setState
package:flutter/…/widgets/framework.dart:1138
flutter: #3 _ModalScopeState._routeSetState
package:flutter/…/widgets/routes.dart:622
flutter: #4 ModalRoute.setState
package:flutter/…/widgets/routes.dart:721
flutter: #5 ModalRoute.changedInternalState
package:flutter/…/widgets/routes.dart:1192
flutter: #6 _ModalRoute&TransitionRoute&LocalHistoryRoute.removeLocalHistoryEntry
package:flutter/…/widgets/routes.dart:506
flutter: #7 LocalHistoryEntry.remove
package:flutter/…/widgets/routes.dart:337
flutter: #8 DrawerControllerState.dispose
package:flutter/…/material/drawer.dart:242
flutter: #9 StatefulElement.unmount
package:flutter/…/widgets/framework.dart:3916
flutter: #10 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1696
flutter: #11 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #12 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #13 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #14 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #15 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #16 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #17 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #18 MultiChildRenderObjectElement.visitChildren
package:flutter/…/widgets/framework.dart:4965
flutter: #19 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #20 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #21 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #22 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #23 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #24 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #25 _InactiveElements._unmount
flutter: #29 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #30 SingleChildRenderObjectElement.visitChildren
package:flutter/…/widgets/framework.dart:4864
flutter: #31 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #32 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #33 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #34 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #35 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #36 SingleChildRenderObjectElement.visitChildren
package:flutter/…/widgets/framework.dart:4864
flutter: #37 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #38 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #39 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #40 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #41 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #42 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #43 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #44 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #45 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #46 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #47 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #48 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #49 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #50 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #51 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #52 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #53 _InactiveElements._unmount.
package:flutter/…/widgets/framework.dart:1694
flutter: #54 ComponentElement.visitChildren
package:flutter/…/widgets/framework.dart:3770
flutter: #55 _InactiveElements._unmount
package:flutter/…/widgets/framework.dart:1692
flutter: #56 ListIterable.forEach (dart:_internal/iterable.dart:39:13)
flutter: #57 _InactiveElements._unmountAll
package:flutter/…/widgets/framework.dart:1705
flutter: #58 BuildOwner.finalizeTree.
package:flutter/…/widgets/framework.dart:2359
flutter: #59 BuildOwner.lockState
package:flutter/…/widgets/framework.dart:2191
flutter: #60 BuildOwner.finalizeTree
package:flutter/…/widgets/framework.dart:2358
flutter: #61 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding&WidgetsBinding.drawFrame
package:flutter/…/widgets/binding.dart:702
flutter: #62 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding._handlePersistentFrameCallback
package:flutter/…/rendering/binding.dart:268
flutter: #63 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback
package:flutter/…/scheduler/binding.dart:988
flutter: #64 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame
flutter: #65 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._handleDrawFrame
package:flutter/…/scheduler/binding.dart:840
flutter: #69 _invoke (dart:ui/hooks.dart:209:10)
flutter: #70 _drawFrame (dart:ui/hooks.dart:168:3)
flutter: (elided 3 frames from package dart:async)
flutter: ════════════════════════════════════════════════════════════════════════════════════════════════════
flutter: Transition { currentState: AuthenticationLoading, event: LoggedOut, nextState: AuthenticationUnauthenticated }

Thank you for your help and sorry to disturb you

boukmi picture boukmi on 4 Mar 2019

No problem! Can you please share the full source code with me on github?

felangel picture felangel on 4 Mar 2019

Of course and thank you so much!

Here is the link to the github repository
https://github.com/boukmi/flutter_login

boukmi picture boukmi on 4 Mar 2019

@boukmi I just opened a PR with some enhancements to make everything work the way I expect you wanted. Let me know if that helps 👍

felangel picture felangel on 4 Mar 2019
👍1

@felangel thank you so much for your help.
I'll check it out in the morning and let you, it's getting late in Europe now 👍

boukmi picture boukmi on 4 Mar 2019
👍1

@boukmi sounds good! Closing this for now but feel free to comment with any further questions/concerns and I'll gladly reopen it 😄

felangel picture felangel on 4 Mar 2019
👍1

It worked 👍 thanks a lot

boukmi picture boukmi on 4 Mar 2019
👍2 🚀1 🎉1

The only downside I see is that it removes animation when navigating between pages.

boukmi picture boukmi on 4 Mar 2019

@boukmi yeah check out
https://github.com/felangel/bloc/issues/18 for one way to retain animations.

felangel picture felangel on 4 Mar 2019
👍1

Awesome I’ll try it!

boukmi picture boukmi on 4 Mar 2019

Hi @felangel and I'm sorry to disturb you again but I'm trying to make this example work perfectly.
I updated the home_page.dart to retain animations like so:

import 'package:flutter/material.dart';

import 'package:flutter_bloc/flutter_bloc.dart';

import 'package:flutter_login/home/home.dart';
import 'package:flutter_login/authentication/authentication.dart';
import 'package:flutter_login/app_drawer.dart';
import 'package:flutter_login/page1.dart';

class HomePage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  final HomeBloc _homeBloc = HomeBloc();
  final PageController _pageController = PageController();

  _HomePageState() {
    _homeBloc.state.listen(
      (state) {
        if (state is HomePageActive) {
          _pageController.animateToPage(
            0, // HomePage
            curve: Curves.ease,
            duration: Duration(milliseconds: 300),
          );
          return;
        }
        if (state is Page1Active) {
          _pageController.animateToPage(
            1, // LoginPage
            curve: Curves.ease,
            duration: Duration(milliseconds: 300),
          );
        }
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      bloc: _homeBloc,
      child: PageView(
        physics: NeverScrollableScrollPhysics(),
        children: [
          _HomePage(),
          Page1(),
        ],
        controller: _pageController,
      ),
    );
  }

  @override
  void dispose() {
    _homeBloc.dispose();
    super.dispose();
  }
}

class _HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final AuthenticationBloc authenticationBloc =
        BlocProvider.of<AuthenticationBloc>(context);

    return Scaffold(
      appBar: AppBar(
        title: Text('Home'),
      ),
      drawer: AppDrawer(),
      body: Container(
        child: Center(
          child: RaisedButton(
            child: Text('logout'),
            onPressed: () {
              authenticationBloc.dispatch(LoggedOut());
            },
          ),
        ),
      ),
    );
  }
}

But I have a strange behaviour when I click on Home button.
animations

Any idea why?

boukmi picture boukmi on 4 Mar 2019

Hi, I am having login n logout issue with bloc, While I am logging in it is not changing the screen on main.dart, I debug it, main.dart bloc builder not updating the state there. While i do hard restart then it changes the screen. here is my code https://github.com/pardipbhatti8791/login-issue . Please help me out with this.

pardipbhatti8791 picture pardipbhatti8791 on 11 Aug 2019

same is happening for the logout. I tried a lot but no solution found yet.

pardipbhatti8791 picture pardipbhatti8791 on 11 Aug 2019

@pardipbhatti8791 I took a look and it's because you're both using BlocProvider and manually disposing the bloc yourself. The rule is whoever creates the bloc should dispose it so whenever you're using BlocProvider(builder: (context) => MyBloc(), child: ...) BlocProvider will automatically handle disposing the bloc for you.

With that said, your TribeApp widget no longer needs to be a StatefulWidget.

class TribeApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final authenticationBloc = BlocProvider.of<IfAuthenticatedBloc>(context);
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: BlocBuilder<IfAuthenticatedBloc, IfAuthenticatedState>(
        builder: (BuildContext context, IfAuthenticatedState state) {
          if (state is Unauthenticated) {
            return SlidesScreen();
          }

          if (state is Authenticated) {
            return Scaffold(
              body: Container(
                child: Center(
                  child: RaisedButton(
                    onPressed: () => authenticationBloc.dispatch(LoggedOut()),
                    child: Text('Log Out'),
                  ),
                ),
              ),
            );
          }

          return SplashScreen();
        },
      ),
      routes: {
        LoginScreen.route: (context) => LoginScreen(),
        SlidesScreen.route: (context) => SlidesScreen(),
      },
    );
  }
}

Hope that helps 👍

felangel picture felangel on 12 Aug 2019

I tried the stateless widget as well without disposing. But still getting
the same. My client is keep asking me updates, And I am stuck here in state
management. Seems like I need to go back to React Native. I am Javascript
developer. I thought should try Flutter I liked it but state management is
huge issue here.

On Mon, Aug 12, 2019 at 3:42 AM Felix Angelov notifications@github.com
wrote:

@pardipbhatti8791 https://github.com/pardipbhatti8791 I took a look and
it's because you're both using BlocProvider and manually disposing the
bloc yourself. The rule is whoever creates the bloc should dispose it so
whenever you're using BlocProvider(builder: (context) => MyBloc(), child:
...) BlocProvider will automatically handle disposing the bloc for you.

With that said, your TribeApp widget no longer needs to be a
StatefulWidget.

class TribeApp extends StatelessWidget {

@override

Widget build(BuildContext context) {

final authenticationBloc = BlocProvider.of<IfAuthenticatedBloc>(context);

return MaterialApp(

  title: 'Flutter Demo',

  theme: ThemeData(

    primarySwatch: Colors.blue,

  ),

  home: BlocBuilder<IfAuthenticatedBloc, IfAuthenticatedState>(

    builder: (BuildContext context, IfAuthenticatedState state) {

      if (state is Unauthenticated) {

        return SlidesScreen();

      }



      if (state is Authenticated) {

        return Scaffold(

          body: Container(

            child: Center(

              child: RaisedButton(

                onPressed: () => authenticationBloc.dispatch(LoggedOut()),

                child: Text('Log Out'),

              ),

            ),

          ),

        );

      }



      return SplashScreen();

    },

  ),

  routes: {

    LoginScreen.route: (context) => LoginScreen(),

    SlidesScreen.route: (context) => SlidesScreen(),

  },

);

}

}

Hope that helps 👍

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pardipbhatti8791 picture pardipbhatti8791 on 12 Aug 2019

Still not taking me home after login, progress Indicator start then nothing
happens. I need to hard restart again then it took me to home screen.

On Mon, Aug 12, 2019 at 3:46 AM Pardip Bhatti pardipbhatti8791@gmail.com
wrote:

I tried the stateless widget as well without disposing. But still getting
the same. My client is keep asking me updates, And I am stuck here in state
management. Seems like I need to go back to React Native. I am Javascript
developer. I thought should try Flutter I liked it but state management is
huge issue here.

On Mon, Aug 12, 2019 at 3:42 AM Felix Angelov notifications@github.com
wrote:

@pardipbhatti8791 https://github.com/pardipbhatti8791 I took a look
and it's because you're both using BlocProvider and manually disposing
the bloc yourself. The rule is whoever creates the bloc should dispose it
so whenever you're using BlocProvider(builder: (context) => MyBloc(),
child: ...) BlocProvider will automatically handle disposing the bloc
for you.

With that said, your TribeApp widget no longer needs to be a
StatefulWidget.

class TribeApp extends StatelessWidget {

@override

Widget build(BuildContext context) {

final authenticationBloc = BlocProvider.of<IfAuthenticatedBloc>(context);

return MaterialApp(

  title: 'Flutter Demo',

  theme: ThemeData(

    primarySwatch: Colors.blue,

  ),

  home: BlocBuilder<IfAuthenticatedBloc, IfAuthenticatedState>(

    builder: (BuildContext context, IfAuthenticatedState state) {

      if (state is Unauthenticated) {

        return SlidesScreen();

      }



      if (state is Authenticated) {

        return Scaffold(

          body: Container(

            child: Center(

              child: RaisedButton(

                onPressed: () => authenticationBloc.dispatch(LoggedOut()),

                child: Text('Log Out'),

              ),

            ),

          ),

        );

      }



      return SplashScreen();

    },

  ),

  routes: {

    LoginScreen.route: (context) => LoginScreen(),

    SlidesScreen.route: (context) => SlidesScreen(),

  },

);

}

}

Hope that helps 👍

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pardipbhatti8791 picture pardipbhatti8791 on 12 Aug 2019

@pardipbhatti8791 can you message me on gitter? I'm more than happy to help you debug the issue further but I don't have valid credentials to actually login.

felangel picture felangel on 12 Aug 2019

Just did

On Mon, Aug 12, 2019 at 4:14 AM Felix Angelov notifications@github.com
wrote:

@pardipbhatti8791 https://github.com/pardipbhatti8791 can you message
me on gitter https://gitter.im/bloc_package/Lobby

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pardipbhatti8791 picture pardipbhatti8791 on 12 Aug 2019

Hi @felangel ,

In my app navigating multiple screens and after came back to HomeScreen in HomeScreen menu click on logout it should go loginScreen but not happening using bloc.
example-1:
i am using bloc in my application and after login->homePage->tabBars->newScreen->anotherNewScreen->click on back to Home screen and if i click on logout it is not navigating to login screen.
example -2:
i am using this example
https://github.com/boukmi/flutter_login
->in the above example also not working multiple navigation.
->in the above example i just added the new screen and navigating from page 1 to newScreen and in newScreen click on logout. then it should move to login screen but not working.

janardhanmupparaju picture janardhanmupparaju on 11 Feb 2020

@janardhanmupparaju if you push new routes onto the stack you need to pop them before you add the LoggedOut event.

Navigator.of(context).popUntil(ModalRoute.withName('/'));
// then add/dispatch LoggedOut()
felangel picture felangel on 11 Feb 2020
🚀1 🎉1

@janardhanmupparaju if you push new routes onto the stack you need to pop them before you add the LoggedOut event.

Navigator.of(context).popUntil(ModalRoute.withName('/'));
// then add/dispatch LoggedOut()

Thank you @felangel , it was working. i just added that line before dispatch LoggedOut().

janardhanmupparaju picture janardhanmupparaju on 12 Feb 2020
🚀1 ❤1 🎉1 😄1 👍1
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