flutter firebase logout fail

Question

state management is too difficult.

Login through firebase works normally and logout works well the first time.

However, if you log in and go to another screen, you cannot log out.

What went wrong?

• logout provider

'''

Future logout() async {
    await firebaseAuth.signOut();
  }

'''

• Pages using logout

'''

Widget build(BuildContext context) {
    final loginProvider = Provider.of<AuthProvider>(context);
    return Scaffold(
        appBar: AppBar(
          actions: [
            IconButton(
              onPressed: () async => await loginProvider.logout(),
              icon: Icon(
                Icons.settings,
                color: Colors.white,
              ),
            )
         
      
        ),

If I modify it like below, it works fine. But I don't know if it's the right way.

'''

onPressed: () async => await loginProvider.logout().then(
                  (value) => Navigator.of(context).pushReplacement(
                      MaterialPageRoute(
                          builder: (BuildContext context) => Wrapper()))),

• Login Provider

'''

Future login(String email, String password) async {
    setLoading(true);
    try {
      UserCredential authResult = await firebaseAuth.signInWithEmailAndPassword(
          email: email, password: password);
      User? user = authResult.user;
      setLoading(false);
      return user;
    } on SocketException {
      setMessage('No internet');
    } catch (e) {
      setLoading(false);
      setMessage(e.toString());
    }
    notifyListeners();
  }

'''

'''

• Login Screen

'''

Container(
                    height: 50.0,
                    margin: EdgeInsets.only(top: 20.0),
                    width: MediaQuery.of(context).size.width * 0.8,
                    child: MaterialButton(
                        color: Color(0xffe50815),
                        shape: RoundedRectangleBorder(
                          borderRadius: BorderRadius.circular(10.0),
                        ),
                        onPressed: () async {
                          if (this._formKey.currentState!.validate()) {
                            print('email : ${this.idCt.text}');
                            print('password : ${this.pwCt.text}');
                            await loginProvider.login(
                                this.idCt.text.trim(), this.pwCt.text.trim());
                          }
                        },
                        child: loginProvider.isLoading
                            ? CircularProgressIndicator()
                            : Text("LOGIN",
                                style: new TextStyle(
                                    fontSize: 12.0,
                                    fontWeight: FontWeight.bold,
                                    color: Colors.white))),
                  ),

'''

• provider

  class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final _init = Firebase.initializeApp();
    return FutureBuilder(
        future: _init,
        builder: (BuildContext context, snapshot) {
          if (snapshot.hasError) {
            return Column(
              children: [
                Icon(Icons.error),
                Center(
                  child: Text('something went wrong!'),
                ),
              ],
            );
          } else if (snapshot.hasData) {
            return MultiProvider(
              providers: [
                ChangeNotifierProvider<AuthProvider>.value(
                  value: AuthProvider(),
                ),
                StreamProvider<User?>.value(
                  value: AuthProvider().user,
                  initialData: null,
                  catchError: (_, err) => null,
                ),
                ChangeNotifierProvider(
                    create: (BuildContext context) =>
                        MovieNowPlayingProvider()),
                ChangeNotifierProvider(
                    create: (BuildContext context) => TvPopularProvider()),
              ],
              child: MaterialApp(
                debugShowCheckedModeBanner: false,
                home: SplashScreen(),
              ),
            );
          }
          return Container();
        });
  }
  

  }

• Wrapper '''

  class Wrapper extends StatelessWidget {
  const Wrapper({Key? key}) : super(key: key);
  
  @override
  Widget build(BuildContext context) {
    final user = Provider.of<User?>(context);
    if (user != null) {
      return MainScreen();
    }
    return Authentication();
  }
  

  }

'''

Answer 1

Using .then and then navigating to the wrapper is not wrong but you might want to restructure the onPressed code to this:

    onPressed: () async {
      await loginProvider.logout();
      Navigator.of(context).pushReplacement(
        MaterialPageRoute(
          builder: (BuildContext context) => Wrapper())
      );
    },

Since you're using async/await, it's more consistent to use just that instead of combining it with .then.