/
cart_bloc.dart
50 lines (38 loc) · 1.31 KB
/
cart_bloc.dart
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import 'dart:async';
import 'package:reactive_exploration/common/models/cart.dart';
import 'package:reactive_exploration/common/models/cart_item.dart';
import 'package:reactive_exploration/common/models/product.dart';
import 'package:rxdart/subjects.dart';
class CartAddition {
final Product product;
final int count;
CartAddition(this.product, [this.count = 1]);
}
class CartBloc {
final Cart _cart = Cart();
final BehaviorSubject<List<CartItem>> _items =
BehaviorSubject<List<CartItem>>(seedValue: []);
final BehaviorSubject<int> _itemCount =
BehaviorSubject<int>(seedValue: 0);
final StreamController<CartAddition> _cartAdditionController =
StreamController<CartAddition>();
CartBloc() {
_cartAdditionController.stream.listen((addition) {
int currentCount = _cart.itemCount;
_cart.add(addition.product, addition.count);
_items.add(_cart.items);
int updatedCount = _cart.itemCount;
if (updatedCount != currentCount) {
_itemCount.add(updatedCount);
}
});
}
Sink<CartAddition> get cartAddition => _cartAdditionController.sink;
Stream<int> get itemCount => _itemCount.stream;
Stream<List<CartItem>> get items => _items.stream;
void dispose() {
_items.close();
_itemCount.close();
_cartAdditionController.close();
}
}