Switch simple state management page to provider

This is switching the example from ScopedModel to Provider.
flutter · filiph · May 22, 2019 · May 22, 2019 · May 22, 2019 · May 22, 2019
commit e2fddaae3a55c4f81635c9f52c27770b06ccc251
diff --git a/examples/state_mgmt/simple/lib/main.dart b/examples/state_mgmt/simple/lib/main.dart
@@ -1,19 +1,15 @@
 import 'package:flutter/material.dart';
-import 'package:scoped_model/scoped_model.dart';
+import 'package:provider/provider.dart';
 import 'package:state_mgmt/src/passing_callbacks.dart' as callbacks;
 import 'package:state_mgmt/src/performance.dart' as performance;
-import 'package:state_mgmt/src/scoped_model.dart';
+import 'package:state_mgmt/src/provider.dart';
 import 'package:state_mgmt/src/set_state.dart' as set_state;
 
 // #docregion main
 void main() {
-  final cart = CartModel();
-
-  // You could optionally connect [cart] with some database here.
-
   runApp(
-    ScopedModel<CartModel>(
-      model: cart,
+    ChangeNotifierProvider(
+      builder: (context) => CartModel(),
       child: MyApp(),
     ),
   );
@@ -22,11 +18,25 @@ void main() {
 
 Map<String, WidgetBuilder> _routes = {
   '/setstate': (context) => set_state.HelperScaffoldWrapper(),
-  '/scoped': (context) => MyHomepage(),
+  '/provider': (context) => MyHomepage(),
   '/callbacks': (context) => callbacks.MyHomepage(),
   '/perf': (context) => performance.MyHomepage(),
 };
 
+// #docregion multi-provider-main
+void multiProviderMain() {
+  runApp(
+    MultiProvider(
+      providers: [
+        ChangeNotifierProvider(builder: (context) => CartModel()),
+        Provider(builder: (context) => SomeOtherClass()),
+      ],
+      child: MyApp(),
+    ),
+  );
+}
+// #enddocregion multi-provider-main
+
 class MyApp extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
@@ -40,6 +50,8 @@ class MyApp extends StatelessWidget {
   }
 }
 
+class SomeOtherClass {}
+
 class _Menu extends StatelessWidget {
   @override
   Widget build(BuildContext context) {

diff --git a/examples/state_mgmt/simple/lib/src/performance.dart b/examples/state_mgmt/simple/lib/src/performance.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
-import 'package:scoped_model/scoped_model.dart';
-import 'package:state_mgmt/src/scoped_model.dart';
+import 'package:provider/provider.dart';
+import 'package:state_mgmt/src/provider.dart';
 
 class AnotherMonstrousWidget extends SomeExpensiveWidget {
   AnotherMonstrousWidget({Widget child}) : super(child: child);
@@ -10,8 +10,8 @@ class ChildUsingDescendant extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     // #docregion child
-    return ScopedModelDescendant<CartModel>(
-      builder: (context, child, cart) => Stack(
+    return Consumer<CartModel>(
+      builder: (context, cart, child) => Stack(
             children: [
               // Use SomeExpensiveWidget here, without rebuilding every time.
               child,
@@ -34,8 +34,8 @@ class DescendantInLeafNode_Good extends StatelessWidget {
       // ...
       child: AnotherMonstrousWidget(
         // ...
-        child: ScopedModelDescendant<CartModel>(
-          builder: (context, child, cart) {
+        child: Consumer<CartModel>(
+          builder: (context, cart, child) {
             return Text('Total price: ${cart.totalPrice}');
           },
         ),
@@ -50,8 +50,8 @@ class DescendantNotInLeafNode_Bad extends StatelessWidget {
   Widget build(BuildContext context) {
     // #docregion nonLeafDescendant
     // DON'T DO THIS
-    return ScopedModelDescendant<CartModel>(
-      builder: (context, child, cart) {
+    return Consumer<CartModel>(
+      builder: (context, cart, child) {
         return HumongousWidget(
           // ...
           child: AnotherMonstrousWidget(
@@ -98,7 +98,7 @@ class NonRebuilding_Good extends StatelessWidget {
   void _onPressed(BuildContext context) {
     var item = Item('Dash');
     // #docregion nonRebuilding
-    ScopedModel.of<CartModel>(context).add(item);
+    Provider.of<CartModel>(context, listen: false).add(item);
     // #enddocregion nonRebuilding
   }
 }

diff --git a/...ate_mgmt/simple/lib/src/scoped_model.dart → ...s/state_mgmt/simple/lib/src/provider.dart b/...ate_mgmt/simple/lib/src/scoped_model.dart → ...s/state_mgmt/simple/lib/src/provider.dart
@@ -1,15 +1,15 @@
 import 'dart:collection';
 
 import 'package:flutter/material.dart';
-import 'package:scoped_model/scoped_model.dart';
+import 'package:provider/provider.dart';
 import 'package:state_mgmt/src/common.dart';
 
 CartModel somehowGetMyCartModel(BuildContext context) {
-  return ScopedModel.of<CartModel>(context, rebuildOnChange: true);
+  return Provider.of<CartModel>(context);
 }
 
 // #docregion model
-class CartModel extends Model {
+class CartModel extends ChangeNotifier {
   /// Internal, private state of the cart.
   final List<Item> _items = [];
 
@@ -42,8 +42,8 @@ class MyCartTotalWidget extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     // #docregion descendant
-    return ScopedModelDescendant<CartModel>(
-      builder: (context, child, cart) {
+    return Consumer<CartModel>(
+      builder: (context, cart, child) {
         return Text("Total price: ${cart.totalPrice}");
       },
     );

diff --git a/examples/state_mgmt/simple/pubspec.yaml b/examples/state_mgmt/simple/pubspec.yaml
@@ -4,15 +4,15 @@ description: Sample state management code.
 version: 1.0.0+1
 
 environment:
-  sdk: ">=2.0.0-dev.68.0 <3.0.0"
+  sdk: ">=2.2.2 <3.0.0"
 
 dependencies:
   flutter:
     sdk: flutter
 
   cupertino_icons: ^0.1.2
 
-  scoped_model: ^1.0.0
+  provider: ^2.0.0
 
 dev_dependencies:
   flutter_test:

diff --git a/examples/state_mgmt/simple/test/model_test.dart b/examples/state_mgmt/simple/test/model_test.dart
@@ -1,4 +1,4 @@
-import 'package:state_mgmt/src/scoped_model.dart';
+import 'package:state_mgmt/src/provider.dart';
 import 'package:test/test.dart';
 
 void main() {

diff --git a/examples/state_mgmt/simple/test/widget_test.dart b/examples/state_mgmt/simple/test/widget_test.dart
@@ -1,15 +1,15 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
-import 'package:scoped_model/scoped_model.dart';
+import 'package:provider/provider.dart';
 import 'package:state_mgmt/main.dart';
-import 'package:state_mgmt/src/scoped_model.dart';
+import 'package:state_mgmt/src/provider.dart';
 
 void main() {
   testWidgets('smoke test', (WidgetTester tester) async {
     // Build our app and trigger a frame.
     await tester.pumpWidget(
-      ScopedModel<CartModel>(
-        model: CartModel(),
+      Provider(
+        builder: (context) => CartModel(),
         child: MyApp(),
       ),
     );

diff --git a/pubspec.lock b/pubspec.lock
@@ -7,7 +7,7 @@ packages:
       name: analyzer
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.36.2"
+    version: "0.36.3"
   args:
     dependency: transitive
     description:
@@ -42,42 +42,42 @@ packages:
       name: build_daemon
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.5.0"
+    version: "0.6.1"
   build_resolvers:
     dependency: transitive
     description:
       name: build_resolvers
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.4"
+    version: "1.0.5"
   build_runner:
     dependency: "direct dev"
     description:
       name: build_runner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.4"
+    version: "1.4.0"
   build_runner_core:
     dependency: transitive
     description:
       name: build_runner_core
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "3.0.4"
+    version: "3.0.5"
   built_collection:
     dependency: transitive
     description:
       name: built_collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "4.2.0"
+    version: "4.2.2"
   built_value:
     dependency: transitive
     description:
       name: built_value
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "6.4.0"
+    version: "6.5.0"
   charcode:
     dependency: transitive
     description:
@@ -172,7 +172,7 @@ packages:
       name: front_end
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.1.17"
+    version: "0.1.18"
   github:
     dependency: "direct dev"
     description:
@@ -242,14 +242,14 @@ packages:
       name: json_annotation
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.2.0"
+    version: "2.4.0"
   kernel:
     dependency: transitive
     description:
       name: kernel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.3.17"
+    version: "0.3.18"
   linkcheck:
     dependency: "direct dev"
     description:
@@ -312,7 +312,7 @@ packages:
       name: pedantic
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.5.0"
+    version: "1.7.0"
   pool:
     dependency: transitive
     description:
@@ -382,7 +382,7 @@ packages:
       name: stream_transform
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.0.18"
+    version: "0.0.19"
   string_scanner:
     dependency: transitive
     description:
@@ -447,4 +447,4 @@ packages:
     source: hosted
     version: "2.1.15"
 sdks:
-  dart: ">=2.2.0 <3.0.0"
+  dart: ">=2.3.0-dev.0.1 <3.0.0"