Creating a cart app using Binder

Let's create our cart application using Binder. You will need to create a new Flutter app named cart_binder, add a dependency for binder and equitable from pub.dev, and copy the item.dart file from the previous section's code into your lib folder. Let's get started:

1. Create a new file named cart_model.dart and add the following imports first:

   import 'package:binder/binder.dart';
   import 'item.dart';

2. Add the following line for getting the static list of items to be shown on the main screen:

   List<Item> items = populateItems();

3. Add the CartModel class underneath the items variable declaration:

   class CartModel {
     List<Item> cart;
     CartModel({required this.cart});
   }

   This class is simple responsible for holding our cart variable:

   final cartRef = StateRef(CartModel(cart: []));
   final cartViewLogicRef = LogicRef((scope) => CartViewLogic(scope));

   As we studied in Chapter 5, Executing...