feat: add interface to shopping cart

packages/flutter_shopping_cart/lib/flutter_shopping_cart.dart

@@ -2,6 +2,5 @@
 library flutter_shopping_cart;
 
 export "src/config/shopping_cart_config.dart";
-export "src/config/shopping_cart_localizations.dart";
+export "src/config/shopping_cart_translations.dart";
-export "src/services/product_service.dart";
 export "src/widgets/shopping_cart_screen.dart";

packages/flutter_shopping_cart/lib/src/config/shopping_cart_config.dart

@@ -1,73 +1,48 @@
 import "package:flutter/material.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_shopping_cart/flutter_shopping_cart.dart";
 import "package:flutter_shopping_cart/src/widgets/product_item_popup.dart";
-
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
-Widget _defaultNoContentBuilder(BuildContext context) =>
-    const SizedBox.shrink();
 
 /// Shopping cart configuration
 ///
 /// This class is used to configure the shopping cart.
-class ShoppingCartConfig<T extends Product> {
+class ShoppingCartConfig {
   /// Creates a shopping cart configuration.
   ShoppingCartConfig({
-    required this.productService,
+    required this.service,
+    required this.onConfirmOrder,
     this.productItemBuilder = _defaultProductItemBuilder,
-    this.onConfirmOrder,
+    this.confirmOrderButtonBuilder = _defaultConfirmOrderButton,
-    this.confirmOrderButtonBuilder,
     this.confirmOrderButtonHeight = 100,
-    this.sumBottomSheetBuilder,
+    this.sumBottomSheetBuilder = _defaultSumBottomSheetBuilder,
     this.sumBottomSheetHeight = 100,
     this.titleBuilder,
-    this.localizations = const ShoppingCartLocalizations(),
+    this.translations = const ShoppingCartTranslations(),
-    this.padding = const EdgeInsets.symmetric(horizontal: 32),
+    this.pagePadding = const EdgeInsets.symmetric(horizontal: 32),
     this.bottomPadding = const EdgeInsets.fromLTRB(44, 0, 44, 32),
-    this.appBar,
+    this.appBar = _defaultAppBar,
-    Widget Function(BuildContext context) noContentBuilder =
+  });
-        _defaultNoContentBuilder,
-  })  : assert(
-          confirmOrderButtonBuilder != null || onConfirmOrder != null,
-          """
-If you override the confirm order button builder,
-you cannot use the onConfirmOrder callback.""",
-        ),
-        assert(
-          confirmOrderButtonBuilder == null || onConfirmOrder == null,
-          """
-If you do not override the confirm order button builder,
-you must use the onConfirmOrder callback.""",
-        ),
-        _noContentBuilder = noContentBuilder;
 
-  /// Product Service. The service contains all the products that
+  /// Product service. The product service is used to manage the products in the
-  /// a shopping cart can contain. Each product must extend the [Product] class.
+  /// shopping cart.
-  /// The service is used to add, remove, and update products.
+  final ShoppingCartService service;
-  ///
-  /// The service can be seperate for each shopping cart in-case you want to
-  /// support seperate shopping carts for shop.
-  ProductService<T> productService = ProductService<T>(<T>[]);
 
   /// Product item builder. This builder is used to build the product item
   /// that will be displayed in the shopping cart.
   final Widget Function(
     BuildContext context,
-    Locale locale,
     Product product,
-    ProductService<Product> productService,
     ShoppingCartConfig configuration,
   ) productItemBuilder;
 
-  final Widget Function(BuildContext context) _noContentBuilder;
-
-  /// No content builder. This builder is used to build the no content widget
-  /// that will be displayed in the shopping cart when there are no products.
-  Widget Function(BuildContext context) get noContentBuilder =>
-      _noContentBuilder;
-
   /// Confirm order button builder. This builder is used to build the confirm
   /// order button that will be displayed in the shopping cart.
   /// If you override this builder, you cannot use the [onConfirmOrder] callback
-  final Widget Function(BuildContext context)? confirmOrderButtonBuilder;
+  final Widget Function(
+    BuildContext context,
+    ShoppingCartConfig configuration,
+    Function(List<Product> products) onConfirmOrder,
+  ) confirmOrderButtonBuilder;
 
   /// Confirm order button height. The height of the confirm order button.
   /// This height is used to calculate the bottom padding of the shopping cart.
@@ -78,12 +53,13 @@ you must use the onConfirmOrder callback.""",
   /// Confirm order callback. This callback is called when the confirm order
   /// button is pressed. The callback will not be called if you override the
   /// confirm order button builder.
-  final Function(List<T> products)? onConfirmOrder;
+  final Function(List<Product> products) onConfirmOrder;
 
   /// Sum bottom sheet builder. This builder is used to build the sum bottom
   /// sheet that will be displayed in the shopping cart. The sum bottom sheet
   /// can be used to display the total sum of the products in the shopping cart.
-  final Widget Function(BuildContext context)? sumBottomSheetBuilder;
+  final Widget Function(BuildContext context, ShoppingCartConfig configuration)
+      sumBottomSheetBuilder;
 
   /// Sum bottom sheet height. The height of the sum bottom sheet.
   /// This height is used to calculate the bottom padding of the shopping cart.
@@ -92,31 +68,30 @@ you must use the onConfirmOrder callback.""",
 
   /// Padding around the shopping cart. The padding is used to create space
   /// around the shopping cart.
-  final EdgeInsets padding;
+  final EdgeInsets pagePadding;
 
   /// Bottom padding of the shopping cart. The bottom padding is used to create
   /// a padding around the bottom sheet. This padding is ignored when the
   /// [sumBottomSheetBuilder] is overridden.
   final EdgeInsets bottomPadding;
 
-  /// Title builder. This builder is used to build the title of the shopping
+  /// Title builder. This builder is used to
-  /// cart. The title is displayed at the top of the shopping cart. If you
+  /// build the title of the shopping cart.
-  /// use the title builder, the [title] will be ignored.
+  final Widget Function(
-  final Widget Function(BuildContext context)? titleBuilder;
+    BuildContext context,
+    String title,
+  )? titleBuilder;
 
-  /// Shopping cart localizations. The localizations are used to localize the
+  /// Shopping cart translations. The translations for the shopping cart.
-  /// shopping cart.
+  final ShoppingCartTranslations translations;
-  final ShoppingCartLocalizations localizations;
 
-  /// App bar for the shopping cart screen.
+  /// Appbar for the shopping cart screen.
-  final PreferredSizeWidget? appBar;
+  final AppBar Function(BuildContext context) appBar;
 }
 
 Widget _defaultProductItemBuilder(
   BuildContext context,
-  Locale locale,
   Product product,
-  ProductService<Product> service,
   ShoppingCartConfig configuration,
 ) {
   var theme = Theme.of(context);
@@ -172,7 +147,8 @@ Widget _defaultProductItemBuilder(
                   Icons.remove,
                   color: Colors.black,
                 ),
-                onPressed: () => service.removeOneProduct(product),
+                onPressed: () =>
+                    configuration.service.removeOneProduct(product),
               ),
               Padding(
                 padding: const EdgeInsets.all(2),
@@ -198,7 +174,7 @@ Widget _defaultProductItemBuilder(
                   Icons.add,
                   color: Colors.black,
                 ),
-                onPressed: () => service.addProduct(product),
+                onPressed: () => configuration.service.addProduct(product),
               ),
             ],
           ),
@@ -207,3 +183,76 @@ Widget _defaultProductItemBuilder(
     ),
   );
 }
+
+Widget _defaultSumBottomSheetBuilder(
+  BuildContext context,
+  ShoppingCartConfig configuration,
+) {
+  var theme = Theme.of(context);
+
+  var totalPrice = configuration.service.products
+      .map((product) => product.price * product.quantity)
+      .fold(0.0, (a, b) => a + b);
+
+  return Padding(
+    padding: configuration.bottomPadding,
+    child: Row(
+      children: [
+        Text(
+          configuration.translations.sum,
+          style: theme.textTheme.titleMedium,
+        ),
+        const Spacer(),
+        Text(
+          "€ ${totalPrice.toStringAsFixed(2)}",
+          style: theme.textTheme.bodyMedium,
+        ),
+      ],
+    ),
+  );
+}
+
+Widget _defaultConfirmOrderButton(
+  BuildContext context,
+  ShoppingCartConfig configuration,
+  Function(List<Product> products) onConfirmOrder,
+) {
+  var theme = Theme.of(context);
+
+  return Padding(
+    padding: const EdgeInsets.symmetric(horizontal: 60),
+    child: SizedBox(
+      width: double.infinity,
+      child: FilledButton(
+        onPressed: () => onConfirmOrder(
+          configuration.service.products,
+        ),
+        style: theme.filledButtonTheme.style?.copyWith(
+          backgroundColor: WidgetStateProperty.all(
+            theme.colorScheme.primary,
+          ),
+        ),
+        child: Padding(
+          padding: const EdgeInsets.symmetric(
+            horizontal: 16.0,
+            vertical: 12,
+          ),
+          child: Text(
+            configuration.translations.placeOrder,
+            style: theme.textTheme.displayLarge,
+          ),
+        ),
+      ),
+    ),
+  );
+}
+
+AppBar _defaultAppBar(BuildContext context) {
+  var theme = Theme.of(context);
+  return AppBar(
+    title: Text(
+      "Shopping cart",
+      style: theme.textTheme.headlineLarge,
+    ),
+  );
+}

packages/flutter_shopping_cart/lib/src/config/shopping_cart_translations.dart

@@ -1,24 +1,14 @@
-import "package:flutter/material.dart";
-
 /// Shopping cart localizations
-class ShoppingCartLocalizations {
+class ShoppingCartTranslations {
   /// Creates shopping cart localizations
-  const ShoppingCartLocalizations({
+  const ShoppingCartTranslations({
-    this.locale = const Locale("en", "US"),
     this.placeOrder = "Order",
     this.sum = "Subtotal:",
     this.cartTitle = "Products",
     this.close = "close",
   });
 
-  /// Locale for the shopping cart.
+  /// Text for the place order button.
-  /// This locale will be used to format the currency.
-  /// Default is English.
-  final Locale locale;
-
-  /// Localization for the place order button.
-  /// This text will only be displayed if you're not using the place order
-  /// button builder.
   final String placeOrder;
 
   /// Localization for the sum.

packages/flutter_shopping_cart/lib/src/services/product_service.dart

@@ -1,71 +0,0 @@
-import "package:flutter/foundation.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
-
-/// Product service. This class is responsible for managing the products.
-/// The service is used to add, remove, and update products.
-class ProductService<T extends Product> extends ChangeNotifier {
-  /// Creates a product service.
-  ProductService(this.products);
-
-  /// List of products in the shopping cart.
-  final List<T> products;
-
-  /// Adds a product to the shopping cart.
-  void addProduct(T product) {
-    for (var p in products) {
-      if (p.id == product.id) {
-        p.quantity++;
-        notifyListeners();
-        return;
-      }
-    }
-
-    products.add(product);
-    notifyListeners();
-  }
-
-  /// Removes a product from the shopping cart.
-  void removeProduct(T product) {
-    for (var p in products) {
-      if (p.id == product.id) {
-        products.remove(p);
-        notifyListeners();
-        return;
-      }
-    }
-    notifyListeners();
-  }
-
-  /// Removes one product from the shopping cart.
-  void removeOneProduct(T product) {
-    for (var p in products) {
-      if (p.id == product.id) {
-        if (p.quantity > 1) {
-          p.quantity--;
-          notifyListeners();
-          return;
-        }
-      }
-    }
-
-    products.remove(product);
-    notifyListeners();
-  }
-
-  /// Counts the number of products in the shopping cart.
-  int countProducts() {
-    var count = 0;
-
-    for (var product in products) {
-      count += product.quantity;
-    }
-
-    return count;
-  }
-
-  /// Empties the shopping cart.
-  void clear() {
-    products.clear();
-    notifyListeners();
-  }
-}

packages/flutter_shopping_cart/lib/src/widgets/product_item_popup.dart

@@ -1,5 +1,6 @@
 import "package:flutter/material.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_shopping_cart/flutter_shopping_cart.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// A popup that displays the product item.
 class ProductItemPopup extends StatelessWidget {
@@ -49,7 +50,7 @@ class ProductItemPopup extends StatelessWidget {
                         vertical: 8.0,
                       ),
                       child: Text(
-                        configuration.localizations.close,
+                        configuration.translations.close,
                         style: theme.textTheme.displayLarge,
                       ),
                     ),

packages/flutter_shopping_cart/lib/src/widgets/shopping_cart_screen.dart

@@ -1,8 +1,8 @@
 import "package:flutter/material.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_shopping_cart/flutter_shopping_cart.dart";
 
 /// Shopping cart screen widget.
-class ShoppingCartScreen<T extends Product> extends StatelessWidget {
+class ShoppingCartScreen extends StatelessWidget {
   /// Creates a shopping cart screen.
   const ShoppingCartScreen({
     required this.configuration,
@@ -10,7 +10,7 @@ class ShoppingCartScreen<T extends Product> extends StatelessWidget {
   });
 
   /// Configuration for the shopping cart screen.
-  final ShoppingCartConfig<T> configuration;
+  final ShoppingCartConfig configuration;
 
   @override
   Widget build(BuildContext context) {
@@ -20,7 +20,10 @@ class ShoppingCartScreen<T extends Product> extends StatelessWidget {
       child: Column(
         children: [
           if (configuration.titleBuilder != null) ...{
-            configuration.titleBuilder!(context),
+            configuration.titleBuilder!(
+              context,
+              configuration.translations.cartTitle,
+            ),
           } else ...{
             Padding(
               padding: const EdgeInsets.symmetric(
@@ -29,7 +32,7 @@ class ShoppingCartScreen<T extends Product> extends StatelessWidget {
               child: Row(
                 children: [
                   Text(
-                    configuration.localizations.cartTitle,
+                    configuration.translations.cartTitle,
                     style: theme.textTheme.titleLarge,
                     textAlign: TextAlign.start,
                   ),
@@ -38,22 +41,16 @@ class ShoppingCartScreen<T extends Product> extends StatelessWidget {
             ),
           },
           ListenableBuilder(
-            listenable: configuration.productService,
+            listenable: configuration.service,
             builder: (context, _) {
-              var products = configuration.productService.products;
+              var products = configuration.service.products;
-
-              if (products.isEmpty) {
-                return configuration.noContentBuilder(context);
-              }
 
               return Column(
                 children: [
                   for (var product in products)
                     configuration.productItemBuilder(
                       context,
-                      configuration.localizations.locale,
                       product,
-                      configuration.productService,
                       configuration,
                     ),
                   // Additional whitespace at the bottom to make sure the
@@ -71,24 +68,18 @@ class ShoppingCartScreen<T extends Product> extends StatelessWidget {
     );
 
     return Scaffold(
-      appBar: configuration.appBar ??
+      appBar: configuration.appBar.call(context),
-          AppBar(
-            title: Text(
-              "Shopping cart",
-              style: theme.textTheme.headlineLarge,
-            ),
-          ),
       body: SafeArea(
         child: Stack(
           fit: StackFit.expand,
           children: [
             Padding(
-              padding: configuration.padding,
+              padding: configuration.pagePadding,
               child: productBuilder,
             ),
             Align(
               alignment: Alignment.bottomCenter,
-              child: _BottomSheet<T>(
+              child: _BottomSheet(
                 configuration: configuration,
               ),
             ),
@@ -99,124 +90,31 @@ class ShoppingCartScreen<T extends Product> extends StatelessWidget {
   }
 }
 
-class _BottomSheet<T extends Product> extends StatelessWidget {
+class _BottomSheet extends StatelessWidget {
   const _BottomSheet({
     required this.configuration,
-    super.key,
-  });
-
-  final ShoppingCartConfig<T> configuration;
-
-  @override
-  Widget build(BuildContext context) {
-    var placeOrderButton = ListenableBuilder(
-      listenable: configuration.productService,
-      builder: (BuildContext context, Widget? child) =>
-          configuration.confirmOrderButtonBuilder != null
-              ? configuration.confirmOrderButtonBuilder!(context)
-              : _DefaultConfirmOrderButton<T>(configuration: configuration),
-    );
-
-    var bottomSheet = ListenableBuilder(
-      listenable: configuration.productService,
-      builder: (BuildContext context, Widget? child) =>
-          configuration.sumBottomSheetBuilder != null
-              ? configuration.sumBottomSheetBuilder!(context)
-              : _DefaultSumBottomSheet(configuration: configuration),
-    );
-
-    return Column(
-      mainAxisSize: MainAxisSize.min,
-      children: [
-        bottomSheet,
-        placeOrderButton,
-      ],
-    );
-  }
-}
-
-class _DefaultConfirmOrderButton<T extends Product> extends StatelessWidget {
-  const _DefaultConfirmOrderButton({
-    required this.configuration,
-  });
-
-  final ShoppingCartConfig<T> configuration;
-
-  @override
-  Widget build(BuildContext context) {
-    var theme = Theme.of(context);
-
-    void onConfirmOrderPressed(List<T> products) {
-      if (configuration.onConfirmOrder == null) {
-        return;
-      }
-
-      if (products.isEmpty) {
-        return;
-      }
-
-      configuration.onConfirmOrder!(products);
-    }
-
-    return Padding(
-      padding: const EdgeInsets.symmetric(horizontal: 60),
-      child: SizedBox(
-        width: double.infinity,
-        child: FilledButton(
-          onPressed: () => onConfirmOrderPressed(
-            configuration.productService.products,
-          ),
-          style: theme.filledButtonTheme.style?.copyWith(
-            backgroundColor: WidgetStateProperty.all(
-              theme.colorScheme.primary,
-            ),
-          ),
-          child: Padding(
-            padding: const EdgeInsets.symmetric(
-              horizontal: 16.0,
-              vertical: 12,
-            ),
-            child: Text(
-              configuration.localizations.placeOrder,
-              style: theme.textTheme.displayLarge,
-            ),
-          ),
-        ),
-      ),
-    );
-  }
-}
-
-class _DefaultSumBottomSheet extends StatelessWidget {
-  const _DefaultSumBottomSheet({
-    required this.configuration,
   });
 
   final ShoppingCartConfig configuration;
 
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context) => Column(
-    var theme = Theme.of(context);
+        mainAxisSize: MainAxisSize.min,
-
-    var totalPrice = configuration.productService.products
-        .map((product) => product.price * product.quantity)
-        .fold(0.0, (a, b) => a + b);
-
-    return Padding(
-      padding: configuration.bottomPadding,
-      child: Row(
         children: [
-          Text(
+          ListenableBuilder(
-            configuration.localizations.sum,
+            listenable: configuration.service,
-            style: theme.textTheme.titleMedium,
+            builder: (BuildContext context, Widget? child) =>
+                configuration.sumBottomSheetBuilder(context, configuration),
+          ),
+          ListenableBuilder(
+            listenable: configuration.service,
+            builder: (BuildContext context, Widget? child) =>
+                configuration.confirmOrderButtonBuilder(
+              context,
+              configuration,
+              configuration.onConfirmOrder,
             ),
-          const Spacer(),
-          Text(
-            "€ ${totalPrice.toStringAsFixed(2)}",
-            style: theme.textTheme.bodyMedium,
           ),
         ],
-      ),
       );
-  }
 }

packages/flutter_shopping_cart/pubspec.yaml

@@ -1,21 +1,23 @@
 name: flutter_shopping_cart
 description: "A Flutter module for a shopping cart."
 version: 2.0.0
-publish_to: 'none'
+publish_to: "none"
 
 environment:
-  sdk: '>=3.3.0 <4.0.0'
+  sdk: ">=3.3.0 <4.0.0"
   flutter: ">=1.17.0"
 
 dependencies:
   flutter:
     sdk: flutter
-  flutter_shopping:
+  flutter_shopping_interface:
     git:
       url: https://github.com/Iconica-Development/flutter_shopping
-      path: packages/flutter_shopping
+      path: packages/flutter_shopping_interface
       ref: 2.0.0
-
+dependency_overrides:
+  flutter_shopping_interface:
+    path: ../flutter_shopping_interface
 
 dev_dependencies:
   flutter_test:

packages/flutter_shopping_interface/lib/src/service/shopping_cart_service.dart

@@ -17,4 +17,7 @@ abstract class ShoppingCartService with ChangeNotifier {
 
   /// Clears the shopping cart.
   void clear();
+
+  /// The list of products in the shopping cart.
+  List<Product> get products;
 }

packages/flutter_shopping_local/lib/service/local_shopping_cart_service.dart

@@ -54,4 +54,7 @@ class LocalShoppingCartService
     }
     notifyListeners();
   }
+
+  @override
+  List<Product> get products => _products;
 }