cubit returns a null value - flutter

Question

I am facing very weird problem. i am using bloc with freezed, injectable and dartz. i just need to get data from SQl database and display it when a today page opened.
The code of UI is:
class TodayPage extends HookWidget {
const TodayPage();
#override
Widget build(BuildContext context) {
return BlocProvider<ScheduledNotesCubit>(
lazy:false,
create: (context) => getIt<ScheduledNotesCubit>()
..countDoneNoteOutOfAllNotes()
..retrieveData(),
child: BlocBuilder<ScheduledNotesCubit, ScheduledNotesState>(
builder: (context, state) {
return ListView.builder(
itemCount: state.maybeMap(
orElse: () {}, getNotesCount: (g) => g.noteCount),
itemBuilder: (BuildContext context, int index) {
return Text(
"${state.maybeMap(orElse: () {}, getNotes: (notes) {
return notes.getNotes[index]['content'];
})}",
);
},
);
},
),
);
}
}
The code of state is:
#freezed
class ScheduledNotesState with _$ScheduledNotesState {
const factory ScheduledNotesState.initial() = _Initial;
const factory ScheduledNotesState.getNotes({required List<Map<String, dynamic>> getNotes}) = _GetNotes;
const factory ScheduledNotesState.getNotesCount({required int noteCount}) = _GetNotesCount;
const factory ScheduledNotesState.getCountDoneNoteOutOfAllNotes({required String getCountDoneNoteOutOfAllNotes}) = _GetCountDoneNoteOutOfAllNotes;
const factory ScheduledNotesState.updateIsDoneNote({required int updateIsDoneNote}) = _UpdateIsDoneNote;
}
The code of cubit is:
#injectable
class ScheduledNotesCubit extends Cubit<ScheduledNotesState> {
ScheduledNotesCubit(this._noteRepository)
: super(const ScheduledNotesState.initial());
final NoteRepository _noteRepository;
// retrieve data
void retrieveData() async {
return emit(ScheduledNotesState.getNotes(
getNotes: await _noteRepository.retrieveData()));
}
}
This Cubit Does not return a value in listView, instead it returns null values, But When i try to do so it works!!!!!!
the updated cubit code is:
#injectable
class ScheduledNotesCubit extends Cubit<ScheduledNotesState> {
ScheduledNotesCubit(this._noteRepository)
: super(const ScheduledNotesState.initial());
final NoteRepository _noteRepository;
// retrieve data
void retrieveData() async {
var d= await _noteRepository.retrieveData(); //-->updated
var x= d[1]['content']; //-->updated
print("\n $x \n") ; // -->updated
return emit(ScheduledNotesState.getNotes(
getNotes: await _noteRepository.retrieveData()));
}
}

Answer 1

Can you try add lazy to false for BlocProvider, and update this code:
void retrieveData() {
_noteRepository.retrieveData().then((value) {
emit(ScheduledNotesState.getNotes(getNotes: value));
});
}

Answer 2

The solution is create a data class for the cubit, instead of creating a sealed classes.