bsev 2.1.0+1

Useful to aid in the use of BloC pattern with dependency injection

[DISCONTINUED]

Our efforts are directed to the new package Cubes.

BSEV (BloC,Streams,Events,View)

Set of packages and utilitarian functions that help in the use of BloC pattern with dependency injection.

With bsev you will use the Bloc pattern in a simple, reactive and organized way. Communication between the business logic and the view occurs entirely through two-way streams.

Usage

To use this plugin, add bsev as a dependency in your pubspec.yaml file.

We should initially create the class Communication and Events:

Streams

import 'package:bsev/bsev.dart';

class HomeCommunication extends Communication{

  var count = BehaviorSubjectCreate<Int>(initValue: 0);
  //var count = StreamCreate<Int>();
  //var count = PublishSubjectCreate<Int>();
  //var count = ReplaySubjectCreate<Int>();

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

}

Events

import 'package:bsev/bsev.dart';

class IncrementEvent extends EventsBase{}

Now we can create our Bloc, class that will be centralized the business rule.

Bloc

import 'package:bsev/bsev.dart';

class HomeBloc extends Bloc<HomeCommunication>{

  // If you need to communicate with some instantiated BloC, regardless of whether part of your tree of widgets can use:
  // dispatchToBloc<OtherBloc>(MsgEvent());

  // If you need send event to all BloCs
  // dispatchToAllBlocs(MyEvent());
  
  // If you need to send an event to the view:
  // dispatchView(MyEvent());

  @override
  void init() {
  // execute something when view is ready.
  }
  
  @override
  void eventReceiver(EventsBase event) {
  
  // called when the Bloc receives an event
  
    if(event is IncrementEvent){
      communication.count.set(streams.count.value + 1)
    }
    
  }
}

In our bloc we have 2 mandatory methods: initState and eventReceiver:

initView: In the first buildView this method is invoked;

eventReceiver: Invoked whenever the pad receives an event;

View

import 'package:bsev/bsev.dart';

class HomeView extends StatelessWidget{
  
  @override
  Widget build(BuildContext context) {
    
    return BsevBuilder<HomeBloc,HomeCommunication>(
      dataToBloc: "any data", //optional initial data to bloc
      eventReceiver: (event, communication){ //optional
        // performs action received by the bloc
      },
      builder: (context,communication){
      
          return Scaffold(
            appBar: AppBar(),
            body: communication.count.builder<int>((value) {
                return Text(value.toString());
            }),
            floatingActionButton: FloatingActionButton(
                onPressed: (){
                  communication.dispatcher(IncrementEvent());
                }
            ),
          );
      
      }
    );
    
  }
  
}

As our Bloc and our StreamsBase will be injected automatically, we should configure it in the Injector in the main of our application:

  MyApp(){

    registerBloc<HomeBloc, HomeCommunication>((i) => HomeBloc(i.get()), () => HomeCommunication());

    //if you want singleton
    //registerSingletonBloc<HomeBloc, HomeCommunication>((i) => HomeBloc(i.get()), () => HomeCommunication());

    //Example of the register any things.
    //registerDependency((i) => CryptoRepository(i.get()));

    //Example of the register any things Singleton.
    //registerSingletonDependency((i) => CryptoRepository(i.get()));

    //Example get dependency anywhere
    //var dependency = getDependency<CryptoRepository>();
    
  }

Questions about how to use the get_it consult documentation.

More complex example is found here

Testing HomeBloc

import 'package:flutter_test/flutter_test.dart';

void main() {
  HomeCommunication _homeCommunication;

  setUp(() {
    _homeCommunication = HomeCommunication();
    _homeCommunication.setBloc(HomeBloc());
  });

  tearDown(() {
    _homeCommunication?.dispose();
  });
  
  test('initial streams', () {
    expect(_homeCommunication.count.value, 0);
  });
  
  test('increment value', () {
    _homeCommunication.dispatcher(IncrementEvent());
    expect(_homeCommunication.count.value, 1);
  });

  test('increment value 3 times', () {
    _homeCommunication.dispatcher(IncrementEvent());
    _homeCommunication.dispatcher(IncrementEvent());
    _homeCommunication.dispatcher(IncrementEvent());
    expect(_homeCommunication.count.value, 3);
  });
  
}

Test example with asynchronous call: here

Used packages

Packages	pub
rxdart
get_it

User cases

Apps
DartLangBr
Boleiro