Cubit state change problem in flutter cubit

Question

So I am trying cubit state management and through that I am trying to login a user to second screen. The error occurs in cubit states changing as it's stuck on initial State. Upon pressing the login button the cubit functions are called for authentication and if the input is right it changes state to authstate else it goes to errorstate.

code of text button where cubit func is called.

TextButton(
    onPressed: () {
      //context.cubit<LoginCubit>().emailAuth(mailController.text!);
      context
          .cubit<LoginCubit>()
          .Auth(mailController.text!, passwordController.text!);
      print('object');
      if (state is AuthState) {
        Navigator.of(context).pushNamed('/Second');
      } else if (state is ErrorState) {
        AlertDialog(
          title: const Text('ERROR'),
          content: Text('retry'),
          actions: <Widget>[
            TextButton(
                onPressed: () {
                  Navigator.of(context).pushNamed('/First');
                },
                child: const Text('retry'))
          ],
        );
      } else {
        print(state.toString());
      }
    },
    child: Text('Login')),

Cubit class:

class LoginCubit extends Cubit<LoginState> {
  LoginCubit() : super(InitialState());
  
  Auth(String email , String password){
    print('test');
    if((email.isEmpty || !email.contains('@'))||(password.isEmpty || password.length < 8)){
      print('test2');
      emit(ErrorState());
    }
    else {
      print('test3');
      emit (AuthState());
    }
    print('test4');
  }
}

Cubit State:

abstract class LoginState{}

class InitialState extends LoginState{

  @override
  String get status => 'Loading';
}
class AuthState extends LoginState{
  @override
  String get status => 'Authenticated';
}

class ErrorState extends LoginState{
  @override
  String get status => 'Error';
}

You have some prints in your code... do you get test2 or test3? — MCB, Oct 12 '22 at 07:08
this is the print o/p: test test2 test4 object Instance of 'InitialState' but despite of getting test2 the state doesnt changes to errorstate — Aditya Pandey, Oct 12 '22 at 07:13
How do you know that the state isn't changing? Because of debugging or because the error page isn't showing? — MCB, Oct 12 '22 at 09:25
Through debugging, however i have found the error. It was a UI error rather than state change issue. Adding solutions to it in the comment. — Aditya Pandey, Oct 13 '22 at 10:32

score 1 · Accepted Answer · answered Oct 12 '22 at 09:19

Follow this way

TextButton(
onPressed: () {
  BlocProvider.of<LoginCubit>(context)
      .Auth("", "");
  final state = BlocProvider.of<LoginCubit>(context).state;

  if (state is AuthState) {
    //   Navigator.of(context).pushNamed('/Second');
    log("Nav to Second");
  } else if (state is ErrorState) {
    log("Dialog");
    //   AlertDialog(
    //     title: const Text('ERROR'),
    //     content: Text('retry'),
    //     actions: <Widget>[
    //       TextButton(
    //           onPressed: () {
    //             Navigator.of(context).pushNamed('/First');
    //           },
    //           child: const Text('retry'))
    //     ],
    //   );
  } else {
    log(state.toString());
  }
},
child: Text('Login')),

score 0 · Answer 2 · answered Oct 13 '22 at 10:34

So I have found the issue and it wasn't of state change rather than it was of UI issue. Where I was calling alertdialog directly rather than building a context for it.

Solution:

showDialog(
                                  context: context,
                                  builder: (BuildContext context)=>AlertDialog(
                                    title: const Text('ERROR'),
                                    content: Text('retry'),
                                    actions: <Widget>[
                                      TextButton(onPressed: (){
                                        Navigator.pop(context);
                                      }, child: const Text('retry'))
                                    ],
                                  )
                              );

Cubit state change problem in flutter cubit

2 Answers2