PostBloc.dart

enum PostBlocAction {FetchPosts}

class PostBloc{

  //This StreamController is used to update the state of widgets
  PublishSubject<PostResponse> _stateStreamController = new PublishSubject();
  StreamSink<PostResponse> get _postSink => _stateStreamController.sink;
  Stream<PostResponse> get postStream => _stateStreamController.stream;

  //user input event StreamController
  PublishSubject<PostBlocAction> _eventStreamController = new PublishSubject();
  StreamSink<PostBlocAction> get eventSink => _eventStreamController.sink;
  Stream<PostBlocAction> get _eventStream => _eventStreamController.stream;

  PostBloc() {
    _eventStream.listen((event) async {
      if (event == PostBlocAction.FetchPosts){
        PostResponse postModel = await ApiController.getPostsData();
        _postSink.add(postModel);
      }

    });
  }

  void dispose(){
    _stateStreamController.close();
    _eventStreamController.close();
  }

}