Flutter pass value to bloc repository - flutter

Question

Trying to study bloc in flutter. I have bloc, events and repository files. I know how to pass data between pages, but i can't pass the parameter to the repository
I need to pass a parameter to the repository for make query to db. For example category id
products_by_category_repository.dart
import 'package:billfort/models/products_model.dart';
import 'package:billfort/strings/strings.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
abstract class ProductsByCategoryRepository {
Future<List<HydraMember>> getProducts();
}
class ProductsByCategoryRepositoryImpl implements ProductsByCategoryRepository {
#override
Future<List<HydraMember>> getProducts() async {
var response = await http.get(Uri.parse("${AppStrings.api}products?category=here need pass id"));
if (response.statusCode == 200) {
var data = json.decode(response.body);
List<HydraMember> products = Products.fromJson(data).hydraMember;
return products;
} else {
throw Exception();
}
}
}
products_bloc.dart
import 'package:bloc/bloc.dart';
import 'package:billfort/bloc/products_event.dart';
import 'package:billfort/bloc/products_state.dart';
import 'package:billfort/models/products_model.dart';
import 'package:billfort/repository/products_repository.dart';
import 'package:meta/meta.dart';
class ProductsBloc extends Bloc < ProductsEvent, ProductsState > {
ProductsRepository repository;
ProductsBloc({
#required this.repository
}): super(null);
#override
// TODO: implement initialState
ProductsState get initialState => ProductsInitialState();
#override
Stream < ProductsState > mapEventToState(ProductsEvent event) async *{
if (event is FetchProductsEvent) {
yield ProductsLoadingState();
try {
List < HydraMember > products = await repository.getProducts();
yield ProductsLoadedState(products: products);
} catch (e) {
yield ProductsErrorState(message: e.toString());
}
}
}
}

Answer 1

If your process of fetching products needs input, then your class FetchProductsEvent should have a property that provides that input, just as your state class ProductsLoadedState for example has a products property that provides the output.
That said, did you upgrade your bloc package without really understanding the changes? Why are you passing null to your base constructor, but still providing an overload for initialState? Your base constructor should get ProductsInitialState() directly and you should remove the overload. If it does not fire warnings for you, you may want to crank up your compiler settings, so your compiler can guide you better.