feat: add interface to flutter_product_page

packages/flutter_product_page/lib/flutter_product_page.dart

@@ -2,11 +2,7 @@
 /// detailed view of each product.
 library flutter_product_page;
 
-export "src/configuration/product_page_category_styling_configuration.dart";
 export "src/configuration/product_page_configuration.dart";
-export "src/configuration/product_page_content.dart";
-export "src/configuration/product_page_localization.dart";
 export "src/configuration/product_page_shop_selector_style.dart";
-export "src/models/product_page_shop.dart";
+export "src/configuration/product_page_translations.dart";
-export "src/ui/product_page.dart";
+export "src/product_page_screen.dart";
-export "src/ui/product_page_screen.dart";

packages/flutter_product_page/lib/src/configuration/product_page_category_styling_configuration.dart

@@ -1,54 +0,0 @@
-import "package:flutter/material.dart";
-import "package:flutter_nested_categories/flutter_nested_categories.dart"
-    show CategoryHeaderStyling;
-
-/// Configuration for the styling of the category list on the product page.
-/// This configuration allows to customize the title, header styling and
-/// the collapsible behavior of the categories.
-class ProductPageCategoryStylingConfiguration {
-  /// Constructor to create a new instance of
-  /// [ProductPageCategoryStylingConfiguration].
-  const ProductPageCategoryStylingConfiguration({
-    this.headerStyling,
-    this.headerCentered = false,
-    this.customTitle,
-    this.title,
-    this.titleStyle,
-    this.titleCentered = false,
-    this.isCategoryCollapsible = true,
-  });
-
-  /// Optional title for the category list. This will be displayed at the
-  /// top of the list.
-  final String? title;
-
-  /// Optional custom title widget for the category list. This will be
-  /// displayed at the top of the list. If set, the text title will be
-  /// ignored.
-  final Widget? customTitle;
-
-  /// Optional title style for the title of the category list. This will
-  /// be applied to the title of the category list. If not set, the default
-  /// text style will be used.
-  final TextStyle? titleStyle;
-
-  /// Configure if the title should be centered.
-  ///
-  /// Default is false.
-  final bool titleCentered;
-
-  /// Optional header styling for the categories. This will be applied to
-  /// the name of the categories. If not set, the default text style will
-  /// be used.
-  final CategoryHeaderStyling? headerStyling;
-
-  /// Configure if the category header should be centered.
-  ///
-  /// Default is false.
-  final bool headerCentered;
-
-  /// Configure if the category should be collapsible.
-  ///
-  /// Default is true.
-  final bool isCategoryCollapsible;
-}

packages/flutter_product_page/lib/src/configuration/product_page_configuration.dart

@@ -1,109 +1,48 @@
 import "package:flutter/material.dart";
-import "package:flutter_product_page/src/services/shopping_cart_notifier.dart";
+import "package:flutter_product_page/flutter_product_page.dart";
-import "package:flutter_product_page/src/ui/widgets/product_item_popup.dart";
+import "package:flutter_product_page/src/widgets/product_item_popup.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// Configuration for the product page.
 class ProductPageConfiguration {
   /// Constructor for the product page configuration.
   ProductPageConfiguration({
+    required this.shoppingService,
     required this.shops,
     required this.getProducts,
     required this.onAddToCart,
     required this.onNavigateToShoppingCart,
-    this.navigateToShoppingCartBuilder = _defaultNavigateToShoppingCartBuilder,
+    required this.getProductsInShoppingCart,
+    this.shoppingCartButtonBuilder = _defaultShoppingCartButtonBuilder,
     this.initialShopId,
     this.productBuilder,
     this.onShopSelectionChange,
-    this.getProductsInShoppingCart,
+    this.translations = const ProductPageTranslations(),
-    this.localizations = const ProductPageLocalization(),
     this.shopSelectorStyle = ShopSelectorStyle.spacedWrap,
-    this.categoryStylingConfiguration =
-        const ProductPageCategoryStylingConfiguration(),
     this.pagePadding = const EdgeInsets.all(4),
     this.appBar = _defaultAppBar,
     this.bottomNavigationBar,
-    Function(
+    this.onProductDetail = _onProductDetail,
-      BuildContext context,
+    this.discountDescription = _defaultDiscountDescription,
-      Product product,
+    this.noContentBuilder = _defaultNoContentBuilder,
-    )? onProductDetail,
+    this.errorBuilder = _defaultErrorBuilder,
-    String Function(
+  });
-      Product product,
-    )? getDiscountDescription,
-    Widget Function(
-      BuildContext context,
-      Product product,
-    )? productPopupBuilder,
-    Widget Function(
-      BuildContext context,
-    )? noContentBuilder,
-    Widget Function(
-      BuildContext context,
-      Object? error,
-      StackTrace? stackTrace,
-    )? errorBuilder,
-  }) {
-    _productPopupBuilder = productPopupBuilder;
-    _productPopupBuilder ??=
-        (BuildContext context, Product product) => ProductItemPopup(
-              product: product,
-              configuration: this,
-            );
 
-    _onProductDetail = onProductDetail;
+  /// The shopping service that is used
-    _onProductDetail ??= (BuildContext context, Product product) async {
+  final ShoppingService shoppingService;
-      var theme = Theme.of(context);
-
-      await showModalBottomSheet(
-        context: context,
-        backgroundColor: theme.colorScheme.surface,
-        builder: (context) => _productPopupBuilder!(
-          context,
-          product,
-        ),
-      );
-    };
-
-    _noContentBuilder = noContentBuilder;
-    _noContentBuilder ??= (BuildContext context) {
-      var theme = Theme.of(context);
-      return Center(
-        child: Text(
-          "No content",
-          style: theme.textTheme.titleLarge,
-        ),
-      );
-    };
-
-    _errorBuilder = errorBuilder;
-    _errorBuilder ??=
-        (BuildContext context, Object? error, StackTrace? stackTrace) {
-      var theme = Theme.of(context);
-      return Center(
-        child: Text(
-          "Error: $error",
-          style: theme.textTheme.titleLarge,
-        ),
-      );
-    };
-
-    _getDiscountDescription = getDiscountDescription;
-    _getDiscountDescription ??= (Product product) =>
-        "${product.name}, now for ${product.discountPrice} each";
-  }
 
   /// The shop that is initially selected.
   final String? initialShopId;
 
   /// A list of all the shops that the user must be able to navigate from.
-  final Future<List<ProductPageShop>> shops;
+  final Future<List<Shop>> Function() shops;
 
   /// A function that returns all the products that belong to a certain shop.
-  /// The function must return a [ProductPageContent] object.
+  /// The function must return a [List<Product>].
-  final Future<ProductPageContent> Function(ProductPageShop shop) getProducts;
+  final Future<List<Product>> Function(Shop shop) getProducts;
 
   /// The localizations for the product page.
-  final ProductPageLocalization localizations;
+  final ProductPageTranslations translations;
 
   /// Builder for the product item. These items will be displayed in the list
   /// for each product in their seperated category. This builder should only
@@ -111,55 +50,24 @@ class ProductPageConfiguration {
   /// in-case the developer does not override it.
   Widget Function(BuildContext context, Product product)? productBuilder;
 
-  late Widget Function(BuildContext context, Product product)?
+  /// The builder for the product popup. This builder should return a widget
-      _productPopupBuilder;
+  Function(
-
+    BuildContext context,
-  /// The builder for the product popup. This popup will be displayed when the
+    Product product,
-  /// user clicks on a product. This builder should only build the widget that
+    String closeText,
-  /// displays the content of one specific product.
+  ) onProductDetail;
-  /// This builder has a default in-case the developer
-  Widget Function(BuildContext context, Product product)
-      get productPopupBuilder => _productPopupBuilder!;
-
-  late Function(BuildContext context, Product product)? _onProductDetail;
-
-  /// This function handles the creation of the product detail popup. This
-  /// function has a default in-case the developer does not override it.
-  /// The default intraction is a popup, but this can be overriden.
-  Function(BuildContext context, Product product) get onProductDetail =>
-      _onProductDetail!;
-
-  late Widget Function(BuildContext context)? _noContentBuilder;
-
-  /// The no content builder is used when a shop has no products. This builder
-  /// has a default in-case the developer does not override it.
-  Function(BuildContext context)? get noContentBuilder => _noContentBuilder;
 
   /// The builder for the shopping cart. This builder should return a widget
   /// that navigates to the shopping cart overview page.
   Widget Function(
     BuildContext context,
     ProductPageConfiguration configuration,
-    ShoppingCartNotifier notifier,
+  ) shoppingCartButtonBuilder;
-  ) navigateToShoppingCartBuilder;
 
-  late Widget Function(
+  /// The function that returns the discount description for a product.
-    BuildContext context,
+  String Function(
-    Object? error,
+    Product product,
-    StackTrace? stackTrace,
+  ) discountDescription;
-  )? _errorBuilder;
-
-  /// The error builder is used when an error occurs. This builder has a default
-  /// in-case the developer does not override it.
-  Widget Function(BuildContext context, Object? error, StackTrace? stackTrace)?
-      get errorBuilder => _errorBuilder;
-
-  late String Function(Product product)? _getDiscountDescription;
-
-  /// The function that returns the description of the discount for a product.
-  /// This allows you to translate and give custom messages for each product.
-  String Function(Product product)? get getDiscountDescription =>
-      _getDiscountDescription!;
 
   /// This function must be implemented by the developer and should handle the
   /// adding of a product to the cart.
@@ -167,11 +75,11 @@ class ProductPageConfiguration {
 
   /// This function gets executed when the user changes the shop selection.
   /// This function always fires upon first load with the initial shop as well.
-  final Function(ProductPageShop shop)? onShopSelectionChange;
+  final Function(Shop shop)? onShopSelectionChange;
 
   /// This function must be implemented by the developer and should handle the
   /// navigation to the shopping cart overview page.
-  final int Function()? getProductsInShoppingCart;
+  final int Function() getProductsInShoppingCart;
 
   /// This function must be implemented by the developer and should handle the
   /// navigation to the shopping cart overview page.
@@ -180,9 +88,6 @@ class ProductPageConfiguration {
   /// The style of the shop selector.
   final ShopSelectorStyle shopSelectorStyle;
 
-  /// The styling configuration for the category list.
-  final ProductPageCategoryStylingConfiguration categoryStylingConfiguration;
-
   /// The padding for the page.
   final EdgeInsets pagePadding;
 
@@ -191,6 +96,20 @@ class ProductPageConfiguration {
 
   /// Optional app bar that you can pass to the order detail screen.
   final AppBar Function(BuildContext context)? appBar;
+
+  /// Builder for the no content widget. This builder is used when there is no
+  /// content to display.
+  final Widget Function(
+    BuildContext context,
+  )? noContentBuilder;
+
+  /// Builder for the error widget. This builder is used when there is an error
+  /// to display.
+  Widget Function(
+    BuildContext context,
+    Object? error,
+    StackTrace? stackTrace,
+  ) errorBuilder;
 }
 
 AppBar _defaultAppBar(
@@ -210,21 +129,21 @@ AppBar _defaultAppBar(
   );
 }
 
-Widget _defaultNavigateToShoppingCartBuilder(
+Widget _defaultShoppingCartButtonBuilder(
   BuildContext context,
   ProductPageConfiguration configuration,
-  ShoppingCartNotifier notifier,
 ) {
   var theme = Theme.of(context);
 
   return ListenableBuilder(
-    listenable: notifier,
+    listenable: configuration.shoppingService.shoppingCartService,
     builder: (context, widget) => Padding(
       padding: const EdgeInsets.symmetric(horizontal: 60),
       child: SizedBox(
         width: double.infinity,
         child: FilledButton(
-          onPressed: configuration.getProductsInShoppingCart?.call() != 0
+          onPressed: configuration
+                  .shoppingService.shoppingCartService.products.isNotEmpty
               ? configuration.onNavigateToShoppingCart
               : null,
           style: theme.filledButtonTheme.style?.copyWith(
@@ -238,7 +157,7 @@ Widget _defaultNavigateToShoppingCartBuilder(
               vertical: 12,
             ),
             child: Text(
-              configuration.localizations.navigateToShoppingCart,
+              configuration.translations.navigateToShoppingCart,
               style: theme.textTheme.displayLarge,
             ),
           ),
@@ -247,3 +166,51 @@ Widget _defaultNavigateToShoppingCartBuilder(
     ),
   );
 }
+
+Future<void> _onProductDetail(
+  BuildContext context,
+  Product product,
+  String closeText,
+) async {
+  var theme = Theme.of(context);
+
+  await showModalBottomSheet(
+    context: context,
+    backgroundColor: theme.colorScheme.surface,
+    builder: (context) => ProductItemPopup(
+      product: product,
+      closeText: closeText,
+    ),
+  );
+}
+
+String _defaultDiscountDescription(
+  Product product,
+) =>
+    "${product.name}, now for ${product.discountPrice} each";
+
+Widget _defaultNoContentBuilder(
+  BuildContext context,
+) {
+  var theme = Theme.of(context);
+  return Center(
+    child: Text(
+      "No content",
+      style: theme.textTheme.titleLarge,
+    ),
+  );
+}
+
+Widget _defaultErrorBuilder(
+  BuildContext context,
+  Object? error,
+  StackTrace? stackTrace,
+) {
+  var theme = Theme.of(context);
+  return Center(
+    child: Text(
+      "Error: $error",
+      style: theme.textTheme.titleLarge,
+    ),
+  );
+}

packages/flutter_product_page/lib/src/configuration/product_page_content.dart

@@ -1,16 +0,0 @@
-import "package:flutter_shopping/flutter_shopping.dart";
-
-/// Return type that contains the products and an optional discounted product.
-class ProductPageContent {
-  /// Default constructor for this class.
-  const ProductPageContent({
-    required this.products,
-    this.discountedProduct,
-  });
-
-  /// List of products that belong to the shop.
-  final List<Product> products;
-
-  /// Optional highlighted discounted product to display.
-  final Product? discountedProduct;
-}

packages/flutter_product_page/lib/src/configuration/product_page_translations.dart

@@ -1,7 +1,7 @@
 /// Localization for the product page
-class ProductPageLocalization {
+class ProductPageTranslations {
   /// Default constructor
-  const ProductPageLocalization({
+  const ProductPageTranslations({
     this.navigateToShoppingCart = "View shopping cart",
     this.discountTitle = "Weekly offer",
     this.failedToLoadImageExplenation = "Failed to load image",

packages/flutter_product_page/lib/src/models/product_page_shop.dart

@@ -1,18 +0,0 @@
-/// The product page shop class contains all the required information
-/// that needs to be known about a certain shop.
-///
-/// In your own implemententation, you must extend from this class so you can
-/// add more fields to this class to suit your needs.
-class ProductPageShop {
-  /// The default constructor for this class.
-  const ProductPageShop({
-    required this.id,
-    required this.name,
-  });
-
-  /// The unique identifier for the shop.
-  final String id;
-
-  /// The name of the shop.
-  final String name;
-}

packages/flutter_product_page/lib/src/product_page_screen.dart

@@ -0,0 +1,238 @@
+import "package:flutter/material.dart";
+import "package:flutter_product_page/flutter_product_page.dart";
+import "package:flutter_product_page/src/services/category_service.dart";
+import "package:flutter_product_page/src/widgets/shop_selector.dart";
+import "package:flutter_product_page/src/widgets/weekly_discount.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
+
+/// A page that displays products.
+class ProductPageScreen extends StatelessWidget {
+  /// Constructor for the product page.
+  const ProductPageScreen({
+    required this.configuration,
+    this.initialBuildShopId,
+    super.key,
+  });
+
+  /// Configuration for the product page.
+  final ProductPageConfiguration configuration;
+
+  /// An optional initial shop ID to select. This overrides the initialShopId
+  /// from the configuration.
+  final String? initialBuildShopId;
+
+  @override
+  Widget build(BuildContext context) => Scaffold(
+        appBar: configuration.appBar!.call(context),
+        bottomNavigationBar: configuration.bottomNavigationBar,
+        body: SafeArea(
+          child: Padding(
+            padding: configuration.pagePadding,
+            child: FutureBuilder(
+              // ignore: discarded_futures
+              future: configuration.shops(),
+              builder: (BuildContext context, AsyncSnapshot data) {
+                if (data.connectionState == ConnectionState.waiting) {
+                  return const Column(
+                    mainAxisSize: MainAxisSize.max,
+                    mainAxisAlignment: MainAxisAlignment.center,
+                    children: [
+                      Center(child: CircularProgressIndicator.adaptive()),
+                    ],
+                  );
+                }
+
+                if (data.hasError) {
+                  return configuration.errorBuilder(
+                    context,
+                    data.error,
+                    data.stackTrace,
+                  );
+                }
+
+                List<Shop>? shops = data.data;
+
+                if (shops == null || shops.isEmpty) {
+                  return configuration.errorBuilder(context, null, null);
+                }
+
+                if (initialBuildShopId != null) {
+                  Shop? initialShop;
+
+                  for (var shop in shops) {
+                    if (shop.id == initialBuildShopId) {
+                      initialShop = shop;
+                      break;
+                    }
+                  }
+
+                  configuration.shoppingService.shopService
+                      .selectShop(initialShop ?? shops.first);
+                } else if (configuration.initialShopId != null) {
+                  Shop? initialShop;
+
+                  for (var shop in shops) {
+                    if (shop.id == configuration.initialShopId) {
+                      initialShop = shop;
+                      break;
+                    }
+                  }
+
+                  configuration.shoppingService.shopService
+                      .selectShop(initialShop ?? shops.first);
+                } else {
+                  configuration.shoppingService.shopService
+                      .selectShop(shops.first);
+                }
+
+                return ListenableBuilder(
+                  listenable: configuration.shoppingService.shopService,
+                  builder: (BuildContext context, Widget? _) {
+                    configuration.onShopSelectionChange?.call(
+                      configuration.shoppingService.shopService.selectedShop!,
+                    );
+                    return _ProductPage(
+                      configuration: configuration,
+                      shops: shops,
+                    );
+                  },
+                );
+              },
+            ),
+          ),
+        ),
+      );
+}
+
+class _ProductPage extends StatelessWidget {
+  const _ProductPage({
+    required this.configuration,
+    required this.shops,
+  });
+
+  final ProductPageConfiguration configuration;
+
+  final List<Shop> shops;
+
+  @override
+  Widget build(BuildContext context) {
+    var pageContent = SingleChildScrollView(
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          ShopSelector(
+            configuration: configuration,
+            shops: shops,
+            onTap: configuration.shoppingService.shopService.selectShop,
+          ),
+          _ShopContents(
+            configuration: configuration,
+          ),
+        ],
+      ),
+    );
+
+    return Stack(
+      children: [
+        pageContent,
+        Align(
+          alignment: Alignment.bottomCenter,
+          child: configuration.shoppingCartButtonBuilder(
+            context,
+            configuration,
+          ),
+        ),
+      ],
+    );
+  }
+}
+
+class _ShopContents extends StatelessWidget {
+  const _ShopContents({
+    required this.configuration,
+  });
+
+  final ProductPageConfiguration configuration;
+
+  @override
+  Widget build(BuildContext context) {
+    var theme = Theme.of(context);
+    return Padding(
+      padding: EdgeInsets.symmetric(
+        horizontal: configuration.pagePadding.horizontal,
+      ),
+      child: FutureBuilder(
+        // ignore: discarded_futures
+        future: configuration.getProducts(
+          configuration.shoppingService.shopService.selectedShop!,
+        ),
+        builder: (context, snapshot) {
+          if (snapshot.connectionState == ConnectionState.waiting) {
+            return const Center(child: CircularProgressIndicator.adaptive());
+          }
+
+          if (snapshot.hasError) {
+            return configuration.errorBuilder(
+              context,
+              snapshot.error,
+              snapshot.stackTrace,
+            );
+          }
+
+          var productPageContent = snapshot.data;
+
+          if (productPageContent == null || productPageContent.isEmpty) {
+            return configuration.noContentBuilder!(context);
+          }
+
+          var productList = Padding(
+            padding: const EdgeInsets.fromLTRB(16, 12, 16, 8),
+            child: Column(
+              children: [
+                // Products
+                getCategoryList(
+                  context,
+                  configuration,
+                  productPageContent,
+                ),
+
+                // Bottom padding so the last product is not cut off
+                // by the to shopping cart button.
+                const SizedBox(height: 48),
+              ],
+            ),
+          );
+          var discountedproducts = productPageContent
+              .where((product) => product.hasDiscount)
+              .toList();
+          return Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              // Discounted product
+              if (discountedproducts.isNotEmpty) ...[
+                Padding(
+                  padding: const EdgeInsets.symmetric(horizontal: 16),
+                  child: WeeklyDiscount(
+                    configuration: configuration,
+                    product: discountedproducts.first,
+                  ),
+                ),
+              ],
+              Padding(
+                padding:
+                    const EdgeInsets.symmetric(horizontal: 16, vertical: 24),
+                child: Text(
+                  "What would you like to order?",
+                  style: theme.textTheme.titleLarge,
+                  textAlign: TextAlign.start,
+                ),
+              ),
+
+              productList,
+            ],
+          );
+        },
+      ),
+    );
+  }
+}

packages/flutter_product_page/lib/src/services/category_service.dart

@@ -1,28 +1,14 @@
 import "package:flutter/material.dart";
 import "package:flutter_nested_categories/flutter_nested_categories.dart";
-import "package:flutter_product_page/src/services/shopping_cart_notifier.dart";
+import "package:flutter_product_page/flutter_product_page.dart";
-import "package:flutter_product_page/src/ui/components/product_item.dart";
+import "package:flutter_product_page/src/widgets/product_item.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
-
-/// A function that is called when a product is added to the cart.
-Product onAddToCartWrapper(
-  ProductPageConfiguration configuration,
-  ShoppingCartNotifier shoppingCartNotifier,
-  Product product,
-) {
-  shoppingCartNotifier.productsChanged();
-
-  configuration.onAddToCart(product);
-
-  return product;
-}
 
 /// Generates a [CategoryList] from a list of [Product]s and a
 /// [ProductPageConfiguration].
 Widget getCategoryList(
   BuildContext context,
   ProductPageConfiguration configuration,
-  ShoppingCartNotifier shoppingCartNotifier,
   List<Product> products,
 ) {
   var theme = Theme.of(context);
@@ -44,12 +30,9 @@ Widget getCategoryList(
               : ProductItem(
                   product: product,
                   onProductDetail: configuration.onProductDetail,
-                  onAddToCart: (Product product) => onAddToCartWrapper(
+                  onAddToCart: (Product product) =>
-                    configuration,
+                      configuration.onAddToCart(product),
-                    shoppingCartNotifier,
+                  translations: configuration.translations,
-                    product,
-                  ),
-                  localizations: configuration.localizations,
                 ),
         )
         .toList();

packages/flutter_product_page/lib/src/services/selected_shop_service.dart

@@ -1,21 +0,0 @@
-import "package:flutter/material.dart";
-import "package:flutter_product_page/src/models/product_page_shop.dart";
-
-/// A service that provides the currently selected shop.
-class SelectedShopService extends ChangeNotifier {
-  /// Creates a [SelectedShopService].
-  SelectedShopService();
-
-  ProductPageShop? _selectedShop;
-
-  /// Updates the selected shop.
-  void selectShop(ProductPageShop shop) {
-    if (_selectedShop == shop) return;
-
-    _selectedShop = shop;
-    notifyListeners();
-  }
-
-  /// The currently selected shop.
-  ProductPageShop? get selectedShop => _selectedShop;
-}

packages/flutter_product_page/lib/src/services/shopping_cart_notifier.dart

@@ -1,10 +0,0 @@
-import "package:flutter/material.dart";
-
-/// Class that notifies listeners when the products in the shopping cart have
-/// changed.
-class ShoppingCartNotifier extends ChangeNotifier {
-  /// Notifies listeners that the products in the shopping cart have changed.
-  void productsChanged() {
-    notifyListeners();
-  }
-}

packages/flutter_product_page/lib/src/ui/product_page.dart

@@ -1,252 +0,0 @@
-import "package:flutter/material.dart";
-import "package:flutter_product_page/flutter_product_page.dart";
-import "package:flutter_product_page/src/services/category_service.dart";
-import "package:flutter_product_page/src/services/selected_shop_service.dart";
-import "package:flutter_product_page/src/services/shopping_cart_notifier.dart";
-import "package:flutter_product_page/src/ui/components/shop_selector.dart";
-import "package:flutter_product_page/src/ui/components/weekly_discount.dart";
-
-/// A page that displays products.
-class ProductPage extends StatelessWidget {
-  /// Constructor for the product page.
-  ProductPage({
-    required this.configuration,
-    this.initialBuildShopId,
-    super.key,
-  });
-
-  /// Configuration for the product page.
-  final ProductPageConfiguration configuration;
-
-  /// An optional initial shop ID to select. This overrides the initialShopId
-  /// from the configuration.
-  final String? initialBuildShopId;
-
-  late final SelectedShopService _selectedShopService = SelectedShopService();
-
-  late final ShoppingCartNotifier _shoppingCartNotifier =
-      ShoppingCartNotifier();
-
-  @override
-  Widget build(BuildContext context) => Padding(
-        padding: configuration.pagePadding,
-        child: FutureBuilder(
-          future: configuration.shops,
-          builder: (BuildContext context, AsyncSnapshot data) {
-            if (data.connectionState == ConnectionState.waiting) {
-              return const Align(
-                alignment: Alignment.center,
-                child: CircularProgressIndicator.adaptive(),
-              );
-            }
-
-            if (data.hasError) {
-              return configuration.errorBuilder!(
-                context,
-                data.error,
-                data.stackTrace,
-              );
-            }
-
-            List<ProductPageShop>? shops = data.data;
-
-            if (shops == null || shops.isEmpty) {
-              return configuration.errorBuilder!(context, null, null);
-            }
-
-            if (initialBuildShopId != null) {
-              ProductPageShop? initialShop;
-
-              for (var shop in shops) {
-                if (shop.id == initialBuildShopId) {
-                  initialShop = shop;
-                  break;
-                }
-              }
-
-              _selectedShopService.selectShop(initialShop ?? shops.first);
-            } else if (configuration.initialShopId != null) {
-              ProductPageShop? initialShop;
-
-              for (var shop in shops) {
-                if (shop.id == configuration.initialShopId) {
-                  initialShop = shop;
-                  break;
-                }
-              }
-
-              _selectedShopService.selectShop(initialShop ?? shops.first);
-            } else {
-              _selectedShopService.selectShop(shops.first);
-            }
-
-            return ListenableBuilder(
-              listenable: _selectedShopService,
-              builder: (BuildContext context, Widget? _) {
-                configuration.onShopSelectionChange?.call(
-                  _selectedShopService.selectedShop!,
-                );
-                return _ProductPage(
-                  configuration: configuration,
-                  selectedShopService: _selectedShopService,
-                  shoppingCartNotifier: _shoppingCartNotifier,
-                  shops: shops,
-                );
-              },
-            );
-          },
-        ),
-      );
-}
-
-class _ProductPage extends StatelessWidget {
-  const _ProductPage({
-    required this.configuration,
-    required this.selectedShopService,
-    required this.shoppingCartNotifier,
-    required this.shops,
-  });
-
-  final ProductPageConfiguration configuration;
-  final SelectedShopService selectedShopService;
-  final ShoppingCartNotifier shoppingCartNotifier;
-
-  final List<ProductPageShop> shops;
-
-  void _onTapChangeShop(ProductPageShop shop) {
-    selectedShopService.selectShop(shop);
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    var pageContent = SingleChildScrollView(
-      child: Column(
-        crossAxisAlignment: CrossAxisAlignment.start,
-        children: [
-          ShopSelector(
-            configuration: configuration,
-            selectedShopService: selectedShopService,
-            shops: shops,
-            onTap: _onTapChangeShop,
-          ),
-          _ShopContents(
-            configuration: configuration,
-            selectedShopService: selectedShopService,
-            shoppingCartNotifier: shoppingCartNotifier,
-          ),
-        ],
-      ),
-    );
-
-    return Stack(
-      children: [
-        pageContent,
-        Align(
-          alignment: Alignment.bottomCenter,
-          child: configuration.navigateToShoppingCartBuilder(
-            context,
-            configuration,
-            shoppingCartNotifier,
-          ),
-        ),
-      ],
-    );
-  }
-}
-
-class _ShopContents extends StatelessWidget {
-  const _ShopContents({
-    required this.configuration,
-    required this.selectedShopService,
-    required this.shoppingCartNotifier,
-  });
-
-  final ProductPageConfiguration configuration;
-  final SelectedShopService selectedShopService;
-  final ShoppingCartNotifier shoppingCartNotifier;
-
-  @override
-  Widget build(BuildContext context) {
-    var theme = Theme.of(context);
-    return Padding(
-      padding: EdgeInsets.symmetric(
-        horizontal: configuration.pagePadding.horizontal,
-      ),
-      child: FutureBuilder(
-        // ignore: discarded_futures
-        future: configuration.getProducts(
-          selectedShopService.selectedShop!,
-        ),
-        builder: (context, snapshot) {
-          if (snapshot.connectionState == ConnectionState.waiting) {
-            return const Align(
-              alignment: Alignment.center,
-              child: CircularProgressIndicator.adaptive(),
-            );
-          }
-
-          if (snapshot.hasError) {
-            return configuration.errorBuilder!(
-              context,
-              snapshot.error,
-              snapshot.stackTrace,
-            );
-          }
-
-          var productPageContent = snapshot.data;
-
-          if (productPageContent == null ||
-              productPageContent.products.isEmpty) {
-            return configuration.noContentBuilder!(context);
-          }
-
-          var productList = Padding(
-            padding: const EdgeInsets.fromLTRB(16, 12, 16, 8),
-            child: Column(
-              children: [
-                // Products
-                getCategoryList(
-                  context,
-                  configuration,
-                  shoppingCartNotifier,
-                  productPageContent.products,
-                ),
-
-                // Bottom padding so the last product is not cut off
-                // by the to shopping cart button.
-                const SizedBox(height: 48),
-              ],
-            ),
-          );
-
-          return Column(
-            crossAxisAlignment: CrossAxisAlignment.start,
-            children: [
-              // Discounted product
-              if (productPageContent.discountedProduct != null) ...[
-                Padding(
-                  padding: const EdgeInsets.symmetric(horizontal: 16),
-                  child: WeeklyDiscount(
-                    configuration: configuration,
-                    product: productPageContent.discountedProduct!,
-                  ),
-                ),
-              ],
-              Padding(
-                padding:
-                    const EdgeInsets.symmetric(horizontal: 16, vertical: 24),
-                child: Text(
-                  "What would you like to order?",
-                  style: theme.textTheme.titleLarge,
-                  textAlign: TextAlign.start,
-                ),
-              ),
-
-              productList,
-            ],
-          );
-        },
-      ),
-    );
-  }
-}

packages/flutter_product_page/lib/src/ui/product_page_screen.dart

@@ -1,36 +0,0 @@
-import "package:flutter/material.dart";
-import "package:flutter_product_page/src/configuration/product_page_configuration.dart";
-import "package:flutter_product_page/src/ui/product_page.dart";
-
-/// A screen that displays a product page. This screen contains a Scaffold,
-/// in which the body is a SafeArea that contains a ProductPage widget.
-///
-/// If you do not wish to create a Scaffold you can use the
-/// [ProductPage] widget directly.
-class ProductPageScreen extends StatelessWidget {
-  /// Constructor for the product page screen.
-  const ProductPageScreen({
-    required this.configuration,
-    this.initialBuildShopId,
-    super.key,
-  });
-
-  /// Configuration for the product page.
-  final ProductPageConfiguration configuration;
-
-  /// An optional initial shop ID to select. This overrides the initialShopId
-  /// from the configuration.
-  final String? initialBuildShopId;
-
-  @override
-  Widget build(BuildContext context) => Scaffold(
-        appBar: configuration.appBar!.call(context),
-        body: SafeArea(
-          child: ProductPage(
-            configuration: configuration,
-            initialBuildShopId: initialBuildShopId,
-          ),
-        ),
-        bottomNavigationBar: configuration.bottomNavigationBar,
-      );
-}

packages/flutter_product_page/lib/src/widgets/horizontal_list_items.dart

@@ -1,5 +1,5 @@
 import "package:flutter/material.dart";
-import "package:flutter_product_page/flutter_product_page.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// Horizontal list of items.
 class HorizontalListItems extends StatelessWidget {
@@ -14,7 +14,7 @@ class HorizontalListItems extends StatelessWidget {
   });
 
   /// List of items.
-  final List<ProductPageShop> shops;
+  final List<Shop> shops;
 
   /// Selected item.
   final String selectedItem;
@@ -26,7 +26,7 @@ class HorizontalListItems extends StatelessWidget {
   final double paddingOnButtons;
 
   /// Callback when an item is tapped.
-  final Function(ProductPageShop shop) onTap;
+  final Function(Shop shop) onTap;
 
   @override
   Widget build(BuildContext context) {

packages/flutter_product_page/lib/src/widgets/product_item.dart

@@ -1,6 +1,7 @@
 import "package:cached_network_image/cached_network_image.dart";
 import "package:flutter/material.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_product_page/flutter_product_page.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 import "package:skeletonizer/skeletonizer.dart";
 
 /// Product item widget.
@@ -10,7 +11,7 @@ class ProductItem extends StatelessWidget {
     required this.product,
     required this.onProductDetail,
     required this.onAddToCart,
-    required this.localizations,
+    required this.translations,
     super.key,
   });
 
@@ -18,13 +19,17 @@ class ProductItem extends StatelessWidget {
   final Product product;
 
   /// Function to call when the product detail is requested.
-  final Function(BuildContext context, Product selectedProduct) onProductDetail;
+  final Function(
+    BuildContext context,
+    Product selectedProduct,
+    String closeText,
+  ) onProductDetail;
 
   /// Function to call when the product is added to the cart.
   final Function(Product selectedProduct) onAddToCart;
 
   /// Localizations for the product page.
-  final ProductPageLocalization localizations;
+  final ProductPageTranslations translations;
 
   /// Size of the product image.
   static const double imageSize = 44;
@@ -46,7 +51,7 @@ class ProductItem extends StatelessWidget {
         fit: BoxFit.cover,
         placeholder: (context, url) => loadingImageSkeleton,
         errorWidget: (context, url, error) => Tooltip(
-          message: localizations.failedToLoadImageExplenation,
+          message: translations.failedToLoadImageExplenation,
           child: Container(
             width: 48,
             height: 48,
@@ -74,7 +79,11 @@ class ProductItem extends StatelessWidget {
     var productInformationIcon = Padding(
       padding: const EdgeInsets.only(left: 4),
       child: IconButton(
-        onPressed: () => onProductDetail(context, product),
+        onPressed: () => onProductDetail(
+          context,
+          product,
+          translations.close,
+        ),
         icon: Icon(
           Icons.info_outline,
           color: theme.colorScheme.primary,

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

@@ -1,12 +1,12 @@
 import "package:flutter/material.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// A popup that displays the product item.
 class ProductItemPopup extends StatelessWidget {
   /// Constructor for the product item popup.
   const ProductItemPopup({
     required this.product,
-    required this.configuration,
+    required this.closeText,
     super.key,
   });
 
@@ -14,7 +14,7 @@ class ProductItemPopup extends StatelessWidget {
   final Product product;
 
   /// Configuration for the product page.
-  final ProductPageConfiguration configuration;
+  final String closeText;
 
   @override
   Widget build(BuildContext context) {
@@ -49,7 +49,7 @@ class ProductItemPopup extends StatelessWidget {
                         vertical: 8.0,
                       ),
                       child: Text(
-                        configuration.localizations.close,
+                        closeText,
                         style: theme.textTheme.displayLarge,
                       ),
                     ),

packages/flutter_product_page/lib/src/widgets/shop_selector.dart

@@ -1,15 +1,14 @@
 import "package:flutter/material.dart";
 import "package:flutter_product_page/flutter_product_page.dart";
-import "package:flutter_product_page/src/services/selected_shop_service.dart";
+import "package:flutter_product_page/src/widgets/horizontal_list_items.dart";
-import "package:flutter_product_page/src/ui/widgets/horizontal_list_items.dart";
+import "package:flutter_product_page/src/widgets/spaced_wrap.dart";
-import "package:flutter_product_page/src/ui/widgets/spaced_wrap.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// Shop selector widget that displays a list to navigate between shops.
 class ShopSelector extends StatelessWidget {
   /// Constructor for the shop selector.
   const ShopSelector({
     required this.configuration,
-    required this.selectedShopService,
     required this.shops,
     required this.onTap,
     this.paddingBetweenButtons = 4,
@@ -21,13 +20,12 @@ class ShopSelector extends StatelessWidget {
   final ProductPageConfiguration configuration;
 
   /// Service for the selected shop.
-  final SelectedShopService selectedShopService;
 
   /// List of shops.
-  final List<ProductPageShop> shops;
+  final List<Shop> shops;
 
   /// Callback when a shop is tapped.
-  final Function(ProductPageShop shop) onTap;
+  final Function(Shop shop) onTap;
 
   /// Padding between the buttons.
   final double paddingBetweenButtons;
@@ -44,7 +42,8 @@ class ShopSelector extends StatelessWidget {
     if (configuration.shopSelectorStyle == ShopSelectorStyle.spacedWrap) {
       return SpacedWrap(
         shops: shops,
-        selectedItem: selectedShopService.selectedShop!.id,
+        selectedItem:
+            configuration.shoppingService.shopService.selectedShop!.id,
         onTap: onTap,
         width: MediaQuery.of(context).size.width - (16 * 2),
         paddingBetweenButtons: paddingBetweenButtons,
@@ -54,7 +53,7 @@ class ShopSelector extends StatelessWidget {
 
     return HorizontalListItems(
       shops: shops,
-      selectedItem: selectedShopService.selectedShop!.id,
+      selectedItem: configuration.shoppingService.shopService.selectedShop!.id,
       onTap: onTap,
       paddingBetweenButtons: paddingBetweenButtons,
       paddingOnButtons: paddingOnButtons,

packages/flutter_product_page/lib/src/widgets/spaced_wrap.dart

@@ -1,5 +1,5 @@
 import "package:flutter/material.dart";
-import "package:flutter_product_page/flutter_product_page.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// SpacedWrap is a widget that wraps a list of items that are spaced out and
 /// fill the available width.
@@ -16,7 +16,7 @@ class SpacedWrap extends StatelessWidget {
   });
 
   /// List of items.
-  final List<ProductPageShop> shops;
+  final List<Shop> shops;
 
   /// Selected item.
   final String selectedItem;
@@ -31,7 +31,7 @@ class SpacedWrap extends StatelessWidget {
   final double paddingOnButtons;
 
   /// Callback when an item is tapped.
-  final Function(ProductPageShop shop) onTap;
+  final Function(Shop shop) onTap;
 
   @override
   Widget build(BuildContext context) {

packages/flutter_product_page/lib/src/widgets/weekly_discount.dart

@@ -1,6 +1,7 @@
 import "package:cached_network_image/cached_network_image.dart";
 import "package:flutter/material.dart";
-import "package:flutter_shopping/flutter_shopping.dart";
+import "package:flutter_product_page/flutter_product_page.dart";
+import "package:flutter_shopping_interface/flutter_shopping_interface.dart";
 
 /// A widget that displays a weekly discount.
 class WeeklyDiscount extends StatelessWidget {
@@ -27,7 +28,7 @@ class WeeklyDiscount extends StatelessWidget {
     var bottomText = Padding(
       padding: const EdgeInsets.all(20.0),
       child: Text(
-        configuration.getDiscountDescription!(product),
+        configuration.discountDescription(product),
         style: theme.textTheme.bodyMedium,
         textAlign: TextAlign.left,
       ),
@@ -50,7 +51,7 @@ class WeeklyDiscount extends StatelessWidget {
               Icons.error_outline_rounded,
               color: Colors.red,
             ),
-            Text(configuration.localizations.failedToLoadImageExplenation),
+            Text(configuration.translations.failedToLoadImageExplenation),
           ],
         ),
       ),
@@ -86,7 +87,7 @@ class WeeklyDiscount extends StatelessWidget {
             horizontal: 16,
           ),
           child: Text(
-            configuration.localizations.discountTitle,
+            configuration.translations.discountTitle,
             style: theme.textTheme.headlineSmall,
             textAlign: TextAlign.left,
           ),

packages/flutter_product_page/pubspec.yaml

@@ -1,10 +1,10 @@
 name: flutter_product_page
 description: "A Flutter module for the product page"
-publish_to: 'none'
+publish_to: "none"
 version: 2.0.0
 
 environment:
-  sdk: '>=3.3.4 <4.0.0'
+  sdk: ">=3.3.4 <4.0.0"
 
 dependencies:
   flutter:
@@ -15,11 +15,17 @@ dependencies:
     git:
       url: https://github.com/Iconica-Development/flutter_nested_categories
       ref: 0.0.1
-  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
+  collection: ^1.18.0
+  provider: ^6.1.2
+
+dependency_overrides:
+  flutter_shopping_interface:
+    path: ../flutter_shopping_interface
 
 dev_dependencies:
   flutter_test:

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

@@ -95,7 +95,9 @@ Widget _defaultProductItemBuilder(
   ShoppingCartConfig configuration,
 ) {
   var theme = Theme.of(context);
-  return Padding(
+  return ListenableBuilder(
+    listenable: configuration.service,
+    builder: (context, _) => Padding(
       padding: const EdgeInsets.only(bottom: 20),
       child: ListTile(
         contentPadding: const EdgeInsets.only(top: 3, left: 4, bottom: 3),
@@ -107,6 +109,8 @@ Widget _defaultProductItemBuilder(
               style: theme.textTheme.titleMedium,
             ),
             IconButton(
+              padding: EdgeInsets.zero,
+              constraints: const BoxConstraints(),
               onPressed: () async {
                 await showModalBottomSheet(
                   context: context,
@@ -132,10 +136,22 @@ Widget _defaultProductItemBuilder(
         ),
         trailing: Column(
           children: [
+            Row(
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                if (product.hasDiscount && product.discountPrice != null) ...[
+                  Text(
+                    product.discountPrice!.toStringAsFixed(2),
+                    style: theme.textTheme.labelSmall,
+                  ),
+                ] else ...[
                   Text(
                     product.price.toStringAsFixed(2),
                     style: theme.textTheme.labelSmall,
                   ),
+                ],
+              ],
+            ),
             Row(
               mainAxisAlignment: MainAxisAlignment.end,
               mainAxisSize: MainAxisSize.min,
@@ -174,13 +190,16 @@ Widget _defaultProductItemBuilder(
                     Icons.add,
                     color: Colors.black,
                   ),
-                onPressed: () => configuration.service.addProduct(product),
+                  onPressed: () {
+                    configuration.service.addProduct(product);
+                  },
                 ),
               ],
             ),
           ],
         ),
       ),
+    ),
   );
 }
 
@@ -190,9 +209,12 @@ Widget _defaultSumBottomSheetBuilder(
 ) {
   var theme = Theme.of(context);
 
-  var totalPrice = configuration.service.products
+  var totalPrice = configuration.service.products.fold<double>(
-      .map((product) => product.price * product.quantity)
+    0,
-      .fold(0.0, (a, b) => a + b);
+    (previousValue, element) =>
+        previousValue +
+        (element.discountPrice ?? element.price) * element.quantity,
+  );
 
   return Padding(
     padding: configuration.bottomPadding,
@@ -218,13 +240,14 @@ Widget _defaultConfirmOrderButton(
   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(
+        onPressed: configuration.service.products.isEmpty
+            ? null
+            : () => onConfirmOrder(
                   configuration.service.products,
                 ),
         style: theme.filledButtonTheme.style?.copyWith(

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

@@ -16,7 +16,15 @@ class ShoppingCartScreen extends StatelessWidget {
   Widget build(BuildContext context) {
     var theme = Theme.of(context);
 
-    var productBuilder = SingleChildScrollView(
+    return Scaffold(
+      appBar: configuration.appBar.call(context),
+      body: SafeArea(
+        child: Stack(
+          fit: StackFit.expand,
+          children: [
+            Padding(
+              padding: configuration.pagePadding,
+              child: SingleChildScrollView(
                 child: Column(
                   children: [
                     if (configuration.titleBuilder != null) ...{
@@ -42,40 +50,28 @@ class ShoppingCartScreen extends StatelessWidget {
                     },
                     ListenableBuilder(
                       listenable: configuration.service,
-            builder: (context, _) {
+                      builder: (context, _) => Column(
-              var products = configuration.service.products;
-
-              return Column(
                         children: [
-                  for (var product in products)
+                          for (var product in configuration.service.products)
                             configuration.productItemBuilder(
                               context,
                               product,
                               configuration,
                             ),
-                  // Additional whitespace at the bottom to make sure the
+
-                  // last product(s) are not hidden by the bottom sheet.
+                          // Additional whitespace at
+                          // the bottom to make sure the last
+                          // product(s) are not hidden by the bottom sheet.
                           SizedBox(
                             height: configuration.confirmOrderButtonHeight +
                                 configuration.sumBottomSheetHeight,
                           ),
                         ],
-              );
+                      ),
-            },
                     ),
                   ],
                 ),
-    );
+              ),
-
-    return Scaffold(
-      appBar: configuration.appBar.call(context),
-      body: SafeArea(
-        child: Stack(
-          fit: StackFit.expand,
-          children: [
-            Padding(
-              padding: configuration.pagePadding,
-              child: productBuilder,
             ),
             Align(
               alignment: Alignment.bottomCenter,
@@ -108,8 +104,7 @@ class _BottomSheet extends StatelessWidget {
           ),
           ListenableBuilder(
             listenable: configuration.service,
-            builder: (BuildContext context, Widget? child) =>
+            builder: (context, _) => configuration.confirmOrderButtonBuilder(
-                configuration.confirmOrderButtonBuilder(
               context,
               configuration,
               configuration.onConfirmOrder,