Skip to content

Instantly share code, notes, and snippets.

@felangel felangel/main.dart
Last active Aug 29, 2019

Embed
What would you like to do?
Recipe: Bloc Access (Routes)
import 'package:flutter/material.dart';
import 'package:bloc/bloc.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
class SimpleBlocDelegate extends BlocDelegate {
@override
void onEvent(Bloc bloc, Object event) {
super.onEvent(bloc, event);
print(event);
}
@override
void onTransition(Bloc bloc, Transition transition) {
super.onTransition(bloc, transition);
print(transition);
}
@override
void onError(Bloc bloc, Object error, StackTrace stacktrace) {
super.onError(bloc, error, stacktrace);
print(error);
}
}
void main() {
BlocSupervisor.delegate = SimpleBlocDelegate();
runApp(App());
}
class App extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
home: BlocProvider(
builder: (BuildContext context) => CounterBloc(),
child: HomePage(),
),
);
}
}
class HomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
final counterBloc = BlocProvider.of<CounterBloc>(context);
return Scaffold(
appBar: AppBar(title: Text('Counter')),
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.of(context).push(
MaterialPageRoute<CounterPage>(
builder: (context) {
return BlocProvider.value(
value: counterBloc,
child: CounterPage(),
);
},
),
);
},
child: Text('Counter'),
),
),
floatingActionButton: Column(
crossAxisAlignment: CrossAxisAlignment.end,
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
Padding(
padding: EdgeInsets.symmetric(vertical: 5.0),
child: FloatingActionButton(
heroTag: 0,
child: Icon(Icons.add),
onPressed: () {
counterBloc.dispatch(CounterEvent.increment);
},
),
),
Padding(
padding: EdgeInsets.symmetric(vertical: 5.0),
child: FloatingActionButton(
heroTag: 1,
child: Icon(Icons.remove),
onPressed: () {
counterBloc.dispatch(CounterEvent.decrement);
},
),
),
],
),
);
}
}
class CounterPage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Counter'),
),
body: BlocBuilder<CounterBloc, int>(
builder: (context, count) {
return Center(
child: Text('$count'),
);
},
),
);
}
}
enum CounterEvent { increment, decrement }
class CounterBloc extends Bloc<CounterEvent, int> {
@override
int get initialState => 0;
@override
Stream<int> mapEventToState(CounterEvent event) async* {
switch (event) {
case CounterEvent.decrement:
yield currentState - 1;
break;
case CounterEvent.increment:
yield currentState + 1;
break;
}
}
}
@SamsadSajid

This comment has been minimized.

Copy link

commented Aug 28, 2019

Where to dispose the counterBloc?

@felangel

This comment has been minimized.

Copy link
Owner Author

commented Aug 29, 2019

@samadsajid it is automatically disposed by BlocProvider when you instantiate it inside the builder.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.