To read from one State to Another in flutter_bloc - flutter

Question

I have been working on an app, here the basic structure looks like.
Having a MultiblocProvider. With two routes.
Route generateRoute(RouteSettings routeSettings) {
switch (routeSettings.name) {
case BASE_ROUTE:
return MaterialPageRoute(
builder: (_) => BlocProvider(
create: (context) => SignupCubit(),
child: SignUp(),
),
);
case OTP_VERIFY:
return MaterialPageRoute(
builder: (_) => MultiBlocProvider(
providers: [
BlocProvider(
create: (context) => VerifyCubit(),
),
BlocProvider(
create: (context) => SignupCubit(),
),
],
child: Verify(),
),
);
default:
return MaterialPageRoute(builder: (_) => Broken());
}
}
In OTP_Verify route I am giving access to two Cubit, VerifyCubit() and SignupCubit().
Now, what i am doing is,
There is two Screen, one is SignUp and the other is Verify. In SignUp Screen, if the state is SignUpSuccess, I am navigating to verify OTP screen.
class SignUp extends StatelessWidget {
const SignUp({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
double deviceHeight = MediaQuery.of(context).size.height;
return Scaffold(
body: BlocListener<SignupCubit, SignupState>(
listener: (context, state) {
if (state is SignUpError) {
showToast("Please try again");
} else if (state is SignupSuccess) {
print(state.email);
Navigator.pushNamed(context, OTP_VERIFY); <--- Here
} else if (state is EmailValidationError) {
showToast("Not valid email");
}
},
child: SafeArea(
bottom: false,
child: CustomScrollView(
slivers: [
.... rest of code....
In VerifyOTP screen, i am trying to read state of current SignUpCubit
....other code....
ElevatedButton(
style: ElevatedButton.styleFrom(
minimumSize: const Size.fromHeight(45),
primary: Theme.of(context).primaryColor),
onPressed: () {
final signUpState = BlocProvider.of<SignupCubit>(context).state; <--- Here
if (signUpState is SignupSuccess) {
print(signUpState.email);
}
BlocProvider.of<VerifyCubit>(context).setOtp(otp);
},
child: const Text('Verify'),
),
.....other code.....
This is my SignUpState
part of 'signup_cubit.dart';
#immutable
abstract class SignupState {}
class SignupIntial extends SignupState {}
class SignUpError extends SignupState {}
class SignupSuccess extends SignupState {
final String email;
SignupSuccess({required this.email});
}
class EmailValidationError extends SignupState {}
Now what I am assuming is I already emitted SignupSuccess in first page and I could read it in second page if I have provided that state by MultiBlocProvider.
But its not happening. Insted I am getting SignUpIntial.
Can someone please help, what i could be doing wrong, or is my method even valid ?

Answer 1

that's because you provide a new instance of the SignupCubit while routing to Verify Screen. thus BlocProvider.of<SignupCubit>(context).state will return the state of the cubit above it which is still in the initial state.
I don't know why you need to check the state of the SignupCubit in the Verify Since you only navigate to it when it's SignupSuccess but anyway, a quick workaround is that you declare and initialize an instance of SignupCubit and use it in the provider around the SignUp and Verify Screens.