Project Bloc

Project Structure

BLoC packages MUST be created in app_bloc/:

app_bloc/
└── feature_name/
    ├── lib/
    │   ├── feature_name_bloc.dart  # Barrel export file
    │   └── src/
    │       ├── bloc.dart           # BLoC class with event handlers
    │       ├── event.dart          # Event definitions
    │       └── state.dart          # State class with status enum
    ├── test/
    │   └── feature_name_bloc_test.dart
    └── pubspec.yaml

BLoC Pattern Conventions

Event Naming

• Events are named as actions: LoadData, SubmitForm, ChangeTheme
• Use past tense for completed actions: DataLoaded, FormSubmitted

State Structure

• States use a status enum: initial, loading, completed, error
• Use copyWith() for immutable state updates
• Extend Equatable for proper state comparison

Event Handlers

• Prefix handlers with _on: _onLoadData, _onSubmitForm
• Use Emitter<State> for state emissions
• Handle errors with try-catch and emit error states

Reference Implementation

ThemeBloc (app_bloc/theme/) serves as the reference implementation:

class ThemeBloc extends Bloc<ThemeEvent, ThemeState> {
  ThemeBloc(this.pref) : super(ThemeState.initial(pref)) {
    on<ChangeTheme>(_onThemeChanged);
    on<ChangeThemeMode>(_onThemeModeChanged);
  }

  Future<void> _onThemeChanged(
    ChangeTheme event,
    Emitter<ThemeState> emitter,
  ) async {
    emitter(state.copyWith(theme: event.theme));
    pref.setString('themeName', event.theme.name);
  }
}

Dependencies

In pubspec.yaml, use workspace resolution: