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У меня небольшая проблема с получением информации из блока. Я только начал изучать flutter_bloc из библиотеки блоков, и мне удалось следовать руководству cubit и обновить свой экран, а также наблюдать за изменениями состояния в консоли. Я решил перенести приложение на использование блока вместо cubit и запутался в том, что видел в консоли. Когда происходит изменение состояния или передается событие, я вижу CounterBloc Instance of 'Decrement' вместо просто Decrement . Я решил переопределить toString методы, чтобы показать просто Decrement , но должен быть лучший способ, верно? Это было не так, когда я использовал локоть.

Это мое контрсобытие.дротик

 part of 'counter_bloc.dart';  @immutable abstract class CounterEvent {}  class Increment extends CounterEvent {  // @override  // String toString() =gt; 'Increment'; }  class Decrement extends CounterEvent {  // @override  // String toString() =gt; 'Decrement'; }  

counter_state.дротик

 part of 'counter_bloc.dart';  @immutable abstract class CounterState {  final int counter;   const CounterState(this.counter);   // @override  // String toString() =gt; 'CounterState(counter: $counter)'; }  class CounterInitial extends CounterState {  const CounterInitial(int counter) : super(counter); }  

counter_bloc.дротик

 import 'package:bloc/bloc.dart'; import 'package:flutter/material.dart'; import 'package:meta/meta.dart';  part 'counter_event.dart'; part 'counter_state.dart';  class CounterBloc extends Bloclt;CounterEvent, CounterStategt; {  CounterBloc() : super(const CounterInitial(0)) {  onlt;Incrementgt;(_onIncrement);  onlt;Decrementgt;(_onDecrement);  }   void _onIncrement(Increment event, Emitterlt;CounterStategt; emit) {  emit(CounterInitial(state.counter   1));  }   void _onDecrement(Decrement event, Emitterlt;CounterStategt; emit) {  emit(CounterInitial(state.counter - 1));  } }  

counter_observer.dart

 // import 'package:bloc/bloc.dart'; import 'package:flutter/material.dart'; import 'package:flutter_bloc/flutter_bloc.dart'; // import 'package:flutter_counter/bloc/counter_bloc.dart'; // import 'package:flutter_counter/bloc/counter_bloc.dart';  /// {@template counter_observer} /// [BlocObserver] for the counter application which /// observes all state changes. /// {@endtemplate} class CounterObserver extends BlocObserver {  @override  void onEvent(Bloc bloc, Object? event) {  super.onEvent(bloc, event);  debugPrint('${bloc.runtimeType} $event');  }   @override  void onChange(BlocBase bloc, Change change) {  super.onChange(bloc, change);  debugPrint('${bloc.runtimeType} $change');  }   @override  void onTransition(Bloc bloc, Transition transition) {  super.onTransition(bloc, transition);  debugPrint('${bloc.runtimeType} $transition');  }   @override  void onError(BlocBase bloc, Object error, StackTrace stackTrace) {  super.onError(bloc, error, stackTrace);  debugPrint('${bloc.runtimeType} $error $stackTrace');  } }  

counter_view.dart

 import 'package:flutter/material.dart'; import 'package:flutter_bloc/flutter_bloc.dart'; import 'package:flutter_counter/bloc/counter_bloc.dart'; // import 'package:flutter_counter/counter/counter.dart';  /// {@template counter_view} /// A [StatelessWidget] which reacts to the provided /// [CounterCubit] state and notifies it in response to user input. /// {@endtemplate} class CounterView extends StatelessWidget {  const CounterView({Key? key}) : super(key: key);   @override  Widget build(BuildContext context) {  final textTheme = Theme.of(context).textTheme;  return Scaffold(  appBar: AppBar(  title: const Text('Counter'),  ),  body: Center(  child: BlocBuilderlt;CounterBloc, CounterStategt;(  builder: (context, state) {  return Text(  '${state.counter}',  style: textTheme.headline2,  );  },  ),  ),  floatingActionButton: Column(  mainAxisAlignment: MainAxisAlignment.end,  crossAxisAlignment: CrossAxisAlignment.end,  children: lt;Widgetgt;[  FloatingActionButton(  key: const Key('counterView_increment_floatingActionButton'),  child: const Icon(Icons.add),  onPressed: () =gt; context.readlt;CounterBlocgt;().add(Increment()),  ),  const SizedBox(height: 8),  FloatingActionButton(  key: const Key('counterView_decrement_floatingActionButton'),  child: const Icon(Icons.remove),  onPressed: () =gt; context.readlt;CounterBlocgt;().add(Decrement()),  ),  ],  ),  );  } }  

The cubit I stopped using

 import 'package:bloc/bloc.dart';  /// {@template counter_cubit} /// A [Cubit] which manages an [int] as its state. /// {@endtemplate} class CounterCubit extends Cubitlt;intgt; {  /// {@macro counter_cubit}  CounterCubit() : super(0);   /// Add 1 to the current state.  void increment() =gt; emit(state   1);   /// Subtract 1 from the current state.  void decrement() =gt; emit(state - 1); }  

main.dart

 import 'package:bloc/bloc.dart'; import 'package:flutter/material.dart'; import 'app.dart'; import 'counter_observer.dart';  void main() {  Bloc.observer = CounterObserver();  runApp(const CounterApp()); }  

Edit: I tried testing after overriding toString and it looks like this problem is somehow affecting it.

 ✓ CounterBloc initial state is 0 Expected: CounterInitial:lt;CounterState(counter: 1)gt;  Actual: [CounterInitial:CounterState(counter: 1)]  

counter_bloc_test.dart

 import 'package:bloc_test/bloc_test.dart'; import 'package:flutter_counter/bloc/counter_bloc.dart'; import 'package:test/test.dart';  void main() {  group('CounterBloc', () {  late CounterBloc counterBloc;   setUp(() {  counterBloc = CounterBloc();  });   test('initial state is 0', () {  expect(counterBloc.state, const CounterInitial(0));  });   blocTest(  'emits [1] when CounterEvent.increment is added',  build: () {  return counterBloc;  },  act: (CounterBloc bloc) {  return bloc.add(Increment());  },  expect: () {  return const CounterInitial(1);  },  );   blocTest(  'emits [-1] when CounterEvent.decrement is added',  build: () {  return counterBloc;  },  act: (CounterBloc bloc) {  return bloc.add(Decrement());  },  expect: () {  return const CounterInitial(-1);  },  );  }); }