app init

Author: utpal-barman

lib/main.dart

@@ -35,27 +35,40 @@ class MyApp extends StatelessWidget {
   }
 }
 
+enum PopupValue {
+  showFavorite,
+  showAll,
+}
+
 class MyHomePage extends StatelessWidget {
   MyHomePage({Key key, this.title}) : super(key: key);
 
   final String title;
 
   @override
   Widget build(BuildContext context) {
+    final productContainer = Provider.of<Products>(context);
     return Scaffold(
       appBar: AppBar(
         //leading: Icon(Icons.menu),
         actions: <Widget>[
           PopupMenuButton(
+            onSelected: (_popupValue) {
+              if (_popupValue == PopupValue.showFavorite) {
+                productContainer.showFavorite();
+              } else {
+                productContainer.showAll();
+              }
+            },
             icon: Icon(Icons.more_vert),
             itemBuilder: (_) => [
               PopupMenuItem(
                 child: Text("Only Favorite"),
-                value: 0,
+                value: PopupValue.showFavorite,
               ),
               PopupMenuItem(
                 child: Text("Show All"),
-                value: 1,
+                value: PopupValue.showAll,
               ),
             ],
           ),

lib/model/product.dart

@@ -14,12 +14,12 @@ class Product with ChangeNotifier {
     @required this.description,
     @required this.price,
     @required this.imageUrl,
-    this.isFavourite = true,
+    this.isFavourite = false,
   });
 
   void toggleFavorite() {
-    print("this item is favorite - $isFavourite");
     isFavourite = !isFavourite;
+    print("this item is favorite - $isFavourite");
     notifyListeners();
   }
 }

lib/providers/products.dart

@@ -37,16 +37,27 @@ class Products with ChangeNotifier {
     ),
   ];
 
+  var isFavoriteTapped = false;
+
   List<Product> get items {
+    if (isFavoriteTapped)
+      return _items.where((product) => product.isFavourite).toList();
     return [..._items];
   }
 
   Product findById(String productId) {
     return _items.firstWhere((p) => p.id == productId);
   }
 
-  void addProducts() {
-    //_items.add(value);
+  void showFavorite() {
+    isFavoriteTapped = true;
+    print("show favourite flag ON");
+    notifyListeners();
+  }
+
+  void showAll() {
+    isFavoriteTapped = false;
+    print("show favourite flag OFF");
     notifyListeners();
   }
 }

lib/widgets/product_tile.dart

@@ -11,8 +11,10 @@ class ProductTile extends StatelessWidget {
       borderRadius: BorderRadius.circular(8.0),
       child: InkWell(
         onTap: () {
-          Navigator.of(context)
-              .pushNamed(ProductDetailScreen.routeName, arguments: product.id);
+          Navigator.of(context).pushNamed(
+            ProductDetailScreen.routeName,
+            arguments: product.id,
+          );
         },
         child: GridTile(
           child: Image.network(
@@ -23,7 +25,7 @@ class ProductTile extends StatelessWidget {
             backgroundColor: Colors.black87,
             leading: IconButton(
               icon: Icon(
-                  product.isFavourite ? Icons.favorite_border : Icons.favorite),
+                  product.isFavourite ? Icons.favorite : Icons.favorite_border),
               color: Theme.of(context).accentColor,
               onPressed: () {
                 //toggle here

lib/widgets/products_grid.dart

@@ -8,6 +8,7 @@ class ProductsGrid extends StatelessWidget {
   Widget build(BuildContext context) {
     final productData = Provider.of<Products>(context);
     final productList = productData.items;
+
     return GridView.builder(
       padding: const EdgeInsets.all(10.0),
       gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
@@ -18,8 +19,11 @@ class ProductsGrid extends StatelessWidget {
       ),
       itemCount: productList.length,
       itemBuilder: (BuildContext context, int index) {
-        return ChangeNotifierProvider(
-          create: (_) => productList[index],
+        print(
+            "index is $index ${productList[index].title} isFavoriteStatus: ${productList[index].isFavourite}");
+        return ChangeNotifierProvider.value(
+          value: productList[index],
+          //create: (_) => productList[index],
           child: ProductTile(),
         );
       },