flutter_bloc 4.0.0 how to get event properties/parametrs

Question

I am quite new to this library and BLOC pattern too, I need fetch all products and a single product based on a particular id.

I have seen many examples created using this library , those people are getting parameter by event.paramter

In my case its not working.

Q. How to get event properties while extending equatable?? inside bloc.

events.dart

abstract class ProductsEvent extends Equatable {
  const ProductsEvent();
}
class FetchProducts extends Equatable{
  @override
  List<Object> get props => [];

}

class FetchSingleProduct extends Equatable{
  final int id;
 const FetchSingleProduct({@required this.id}) : assert(id !=null);
  @override
  List<Object> get props => [id];
}

Bloc.dart

class ProductsBloc extends Bloc<ProductsEvent, ProductsState> {
  final AbstractProductsRepository abstractProductsRepository;
  ProductsBloc(this.abstractProductsRepository);

  @override
  ProductsState get initialState => InitialProductsState();

  @override
  Stream<ProductsState> mapEventToState(
    ProductsEvent event,

  ) async* {
    yield ProductsLoadingState();
    if(event is FetchProducts){
      try{

        final productsData = await abstractProductsRepository.fetchProducts();
        yield ProductsLoadedState(productsData);
      }on Error{
        print("Error in Block");
        yield ProductErrorState();
      }
    }else if(event is FetchSingleProduct){
      try{

        //Event.id  - not working.
        final productData = await abstractProductsRepository.fetchSingleProduct(**event.id**);
        yield SingleProductLoaded(productData);
      }on Error{
        print("Error in Block");
        yield ProductErrorState();
      }
    }
  }
}

Thanx @VirenVVarasadiya, My bad , I was extending to equatable for all events instead of event type. By extending Event type Everthing working fine now — techieasif, Apr 23 '20 at 13:39

score 0 · Answer 1 · answered Apr 23 '20 at 13:27

You're supposed to extends ProductsEvent

abstract class ProductsEvent extends Equatable {
  const ProductsEvent();
}

class FetchProducts extends ProductsEvent {
  @override
  List<Object> get props => [];
}

class FetchSingleProduct extends ProductsEvent {
  final int id;

  const FetchSingleProduct({@required this.id}) : assert(id !=null);

  @override
  List<Object> get props => [id];
}

score 0 · Answer 2 · answered Apr 23 '20 at 13:35

You need to Extend ProductsEvent as below and also you have to pass props to super class.

@immutable
abstract class ProductsEvent extends Equatable {
  ProductsEvent([List props = const []]) : super(props);
}

class FetchProducts extends ProductsEvent {
  @override
  String toString() => 'LoadTodos';
}

class FetchSingleProduct extends ProductsEvent {
  final int id;
  AddTodo(this.id) : super([id]);

}

flutter_bloc 4.0.0 how to get event properties/parametrs

2 Answers2