Bloc: State Changes are not Correctly Emitted

Created on 7 May 2020 · 2Comments · Source: felangel/bloc

Describe the bug
I have recently come across the following issue in my project. With this configuration of bloc, state and event classes state changes occur in the BLoC but are not properly emitted. If I add an event to the BLoC, it is registered and the state is changed as expected, but the new state is not emitted.

The UI

````dart
void main() {
runApp(MyApp());
}

class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}

class _MyAppState extends State {
final TestBloc testBloc = TestBloc();

@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'State Demo',
home: BlocBuilder(
bloc: testBloc,
builder: (context, state) {
return Scaffold(
appBar: AppBar(),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
(state as IdleState).entries.toString(),
),
SizedBox(height: 20),
FlatButton(
child: Text("Add Entry"),
onPressed: () => testBloc.add(
AddEntryEvent(
Random().nextInt(100000),
Random().nextInt(100000),
),
),
)
],
),
),
);
}),
);
}

@override
void dispose() {
testBloc.close();
super.dispose();
}
}
````

The BLoC

````dart
class TestBloc extends Bloc {
@override
TestState get initialState => IdleState(HashMap());

@override
Stream mapEventToState(TestEvent event) async* {
if(event is AddEntryEvent && state is IdleState){
HashMap newEntries = (state as IdleState).entries;
newEntries[event.index] = event.entry;

  yield IdleState(newEntries);
}

}
}
````

The State

````dart
abstract class TestState extends Equatable {
const TestState();
}

class IdleState extends TestState {
final HashMap entries;

IdleState(this.entries);

@override
List

Bloc: State Changes are not Correctly Emitted

The UI

The BLoC

The State

The Event

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