Bad state: Cannot emit new states after calling close - flutter

Question

I'm using flutter_form_bloc (https://pub.dev/packages/flutter_form_bloc) and I created two classes, the first is the login page:
class LoginScreen extends StatelessWidget {
const LoginScreen({super.key});
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Flutter - Parse Server',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: FutureBuilder<bool>(
future: hasUserLogged(),
builder: (context, snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.none:
case ConnectionState.waiting:
return SafeArea(
child: Scaffold(
body: Center(
child: Container(
width: 100,
height: 100,
child: CircularProgressIndicator()),
),
),
);
default:
if (snapshot.hasData && snapshot.data!) {
return UserPage();
} else {
return LoginPage();
}
}
}),
);
}
}
class LoginPage extends StatefulWidget {
#override
_LoginPageState createState() => _LoginPageState();
}
class _LoginPageState extends State<LoginPage> {
final controllerUsername = TextEditingController();
final controllerPassword = TextEditingController();
final controllerConfirmPassword = TextEditingController();
bool isLoggedIn = false;
#override
Widget build(BuildContext context) {
return SafeArea(
child: SafeArea(
child: Scaffold(
body: SingleChildScrollView(
...
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
const Text(
'Don\'t have an Account? ',
overflow: TextOverflow.ellipsis,
),
new InkWell(
child: new Text(
'Sign Up',
style: TextStyle(
color: Colors.black,
fontWeight: FontWeight.bold,
),
),
onTap: () => Navigator.of(context).pushReplacement(
MaterialPageRoute(
builder: (_) =>
const listRegistrationScreen2()))),
],
),
),
);
}
class UserPage extends StatelessWidget {
...
}
And the second is list registration:
class listRegistrationScreen2 extends StatelessWidget {
const listRegistrationScreen2({super.key});
#override
Widget build(BuildContext context) {
return _listRegistrationScreen();
}
}
class _listRegistrationScreen extends StatefulWidget {
#override
__listRegistrationScreen createState() => __listRegistrationScreen();
}
class __listRegistrationScreen extends State<_listRegistrationScreen> {
static var flag = false;
...
#override
void initState() {
formBloc = null;
super.initState();
}
#override
void dispose() {
formBloc = null;
super.dispose();
}
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
resizeToAvoidBottomInset: false,
appBar: AppBar(
iconTheme: IconThemeData(
color: Colors.black,
),
centerTitle: true,
actions: [
IconButton(
onPressed: () {
Navigator.of(context).pushReplacement(
MaterialPageRoute(builder: (_) => const LoginScreen()));
},
icon: Icon(Icons.arrow_back))
],
),
body: BlocProvider(
create: (context) => ConditionalFieldsForm(),
child: Builder(
builder: (context) {
formBloc = BlocProvider.of<ConditionalFieldsForm>(context);
return Theme(
data: Theme.of(context).copyWith(
inputDecorationTheme: InputDecorationTheme(
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(20),
),
),
),
child: SafeArea(
child: Scaffold(
body: FormBlocListener<ConditionalFieldsForm, String,
String>(
onSubmitting: {
...
},
onSubmissionFailed: (context, state) {
LoadingDialog.hide(context);
},
onSuccess: (context, state) {
LoadingDialog.hide(context);
},
onFailure: (context, state) {
LoadingDialog.hide(context);
ScaffoldMessenger.of(context).showSnackBar(
SnackBar(content: Text(state.failureResponse!)));
},
child: SingleChildScrollView(
physics: const ClampingScrollPhysics(),
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Column(
...
),
ElevatedButton(
onPressed: formBloc.submit,
child: Text('SUBMIT'),
),
],
),
),
),
),
),
),
);
},
),
)),
);
}
}
class LoadingDialog extends StatelessWidget {
...
}
class ConditionalFieldsForm extends FormBloc<String, String> {
static final roles = SelectFieldBloc(
validators: [FieldBlocValidators.required],
items: ['Trainee', 'Employer', 'Department'],
);
static final TraineeEmail = TextFieldBloc(
validators: [FieldBlocValidators.required, FieldBlocValidators.email],
);
...
ConditionalFieldsForm() {
addFieldBlocs(
fieldBlocs: [
roles,
],
);
...
#override
Future<void> close() {
TraineeEmail.close();
TraineePassword.close();
TraineeConfirmPassword.close();
TraineeDOB.close();
TraineePhoneNumber.close();
TraineeSkills.close();
TraineeNationality.close();
TraineeAddress.close();
TraineeCurrentInstituation.close();
TraineeMajor.close();
TraineeName.close();
TraineeGender.close();
EmployerPhoneNumber.close();
EmployerWebsite.close();
EmployerPassword.close();
EmployerEmail.close();
EmployerAddressID.close();
EmployerDescription.close();
EmployerName.close();
DepartmentPhoneNumber.close();
DepartmentPassword.close();
DepartmentEmail.close();
DepartmentAddressID.close();
DepartmentCategory.close();
DepartmentName.close();
roles.close();
terms.close();
traineeRegistred.close();
employerRegistred.close();
return super.close();
}
#override
onSubmitting() async {
}
}
The problem is when I navigate from login to list registration page then back to login page and try to back again to list registration page I got this error:
error message screen
I tried to use dispose and change login screen from state less to state full but that didn't work with me.