Add Material 3 `FloatingActionButton` and `FloatingActionButton` variants examples (#101105)

examples/api/lib/material/floating_action_button/floating_action_button.0.dart

@@ -11,25 +11,22 @@ void main() => runApp(const MyApp());
 class MyApp extends StatelessWidget {
   const MyApp({Key? key}) : super(key: key);
 
-  static const String _title = 'Flutter Code Sample';
-
   @override
   Widget build(BuildContext context) {
     return const MaterialApp(
-      title: _title,
-      home: MyStatelessWidget(),
+      home: FabExample(),
     );
   }
 }
 
-class MyStatelessWidget extends StatelessWidget {
-  const MyStatelessWidget({Key? key}) : super(key: key);
+class FabExample extends StatelessWidget {
+  const FabExample({Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: const Text('Floating Action Button'),
+        title: const Text('FloatingActionButton Sample'),
       ),
       body: const Center(child: Text('Press the button below!')),
       floatingActionButton: FloatingActionButton(

examples/api/lib/material/floating_action_button/floating_action_button.1.dart

@@ -11,25 +11,22 @@ void main() => runApp(const MyApp());
 class MyApp extends StatelessWidget {
   const MyApp({Key? key}) : super(key: key);
 
-  static const String _title = 'Flutter Code Sample';
-
   @override
   Widget build(BuildContext context) {
     return const MaterialApp(
-      title: _title,
-      home: MyStatelessWidget(),
+      home: FabExample(),
     );
   }
 }
 
-class MyStatelessWidget extends StatelessWidget {
-  const MyStatelessWidget({Key? key}) : super(key: key);
+class FabExample extends StatelessWidget {
+  const FabExample({Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: const Text('Floating Action Button Label'),
+        title: const Text('FloatingActionButton Sample'),
       ),
       body: const Center(
         child: Text('Press the button with a label below!'),

examples/api/lib/material/floating_action_button/floating_action_button.2.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flutter code sample for FloatingActionButton
+
+import 'package:flutter/material.dart';
+
+void main() => runApp(const MyApp());
+
+class MyApp extends StatelessWidget {
+  const MyApp({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      theme: ThemeData(colorSchemeSeed: const Color(0xff6750a4), useMaterial3: true),
+      home: const FabExample(),
+    );
+  }
+}
+
+class FabExample extends StatelessWidget {
+  const FabExample({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('FloatingActionButton Sample'),
+      ),
+      body: const Center(child: Text('Press the button below!')),
+      // An example of the floating action button.
+      //
+      // https://m3.material.io/components/floating-action-button/specs
+      floatingActionButton: FloatingActionButton(
+        onPressed: () {
+          // Add your onPressed code here!
+        },
+        child: const Icon(Icons.add),
+      ),
+    );
+  }
+}

examples/api/lib/material/floating_action_button/floating_action_button.3.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flutter code sample for FloatingActionButton
+
+import 'package:flutter/material.dart';
+
+void main() => runApp(const MyApp());
+
+class MyApp extends StatelessWidget {
+  const MyApp({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      theme: ThemeData(colorSchemeSeed: const Color(0xff6750a4), useMaterial3: true),
+      home: const FabExample(),
+    );
+  }
+}
+
+class FabExample extends StatelessWidget {
+  const FabExample({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('FloatingActionButton Sample'),
+      ),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+          children: <Widget>[
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: <Widget>[
+                const Text('Small'),
+                const SizedBox(width: 16),
+                // An example of the small floating action button.
+                //
+                // https://m3.material.io/components/floating-action-button/specs#669a1be8-7271-48cb-a74d-dd502d73bda4
+                FloatingActionButton.small(
+                  onPressed: () {
+                    // Add your onPressed code here!
+                  },
+                  child: const Icon(Icons.add),
+                ),
+              ],
+            ),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: <Widget>[
+                const Text('Regular'),
+                const SizedBox(width: 16),
+                // An example of the regular floating action button.
+                //
+                // https://m3.material.io/components/floating-action-button/specs#71504201-7bd1-423d-8bb7-07e0291743e5
+                FloatingActionButton(
+                  onPressed: () {
+                    // Add your onPressed code here!
+                  },
+                  child: const Icon(Icons.add),
+                ),
+              ],
+            ),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: <Widget>[
+                const Text('Large'),
+                const SizedBox(width: 16),
+                // An example of the large floating action button.
+                //
+                // https://m3.material.io/components/floating-action-button/specs#9d7d3d6a-bab7-47cb-be32-5596fbd660fe
+                FloatingActionButton.large(
+                  onPressed: () {
+                    // Add your onPressed code here!
+                  },
+                  child: const Icon(Icons.add),
+                ),
+              ],
+            ),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: <Widget>[
+                const Text('Extended'),
+                const SizedBox(width: 16),
+                // An example of the extended floating action button.
+                //
+                // https://m3.material.io/components/extended-fab/specs#686cb8af-87c9-48e8-a3e1-db9da6f6c69b
+                FloatingActionButton.extended(
+                  onPressed: () {
+                    // Add your onPressed code here!
+                  },
+                  label: const Text('Add'),
+                  icon: const Icon(Icons.add),
+                ),
+              ],
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

examples/api/test/material/floating_action_button/floating_action_button.0_test.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_api_samples/material/floating_action_button/floating_action_button.0.dart'
+    as example;
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('FloatingActionButton', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const example.MyApp(),
+    );
+
+    expect(find.byType(FloatingActionButton), findsOneWidget);
+    expect(find.byIcon(Icons.navigation), findsOneWidget);
+
+    final Finder materialButtonFinder = find.byType(RawMaterialButton);
+    RawMaterialButton getRawMaterialButtonWidget() {
+      return tester.widget<RawMaterialButton>(materialButtonFinder);
+    }
+    expect(getRawMaterialButtonWidget().fillColor, Colors.green);
+    expect(getRawMaterialButtonWidget().shape, const CircleBorder());
+  });
+}

examples/api/test/material/floating_action_button/floating_action_button.1_test.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_api_samples/material/floating_action_button/floating_action_button.1.dart'
+    as example;
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('FloatingActionButton.extended', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const example.MyApp(),
+    );
+
+    expect(find.byType(FloatingActionButton), findsOneWidget);
+    expect(find.text('Approve'), findsOneWidget);
+    expect(find.byIcon(Icons.thumb_up), findsOneWidget);
+
+    final Finder materialButtonFinder = find.byType(RawMaterialButton);
+    RawMaterialButton getRawMaterialButtonWidget() {
+      return tester.widget<RawMaterialButton>(materialButtonFinder);
+    }
+    expect(getRawMaterialButtonWidget().fillColor, Colors.pink);
+    expect(getRawMaterialButtonWidget().shape, const StadiumBorder());
+  });
+}

examples/api/test/material/floating_action_button/floating_action_button.2_test.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_api_samples/material/floating_action_button/floating_action_button.2.dart'
+    as example;
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('FloatingActionButton - Material 3', (WidgetTester tester) async {
+    RawMaterialButton getRawMaterialButtonWidget(Finder finder) {
+      return tester.widget<RawMaterialButton>(finder);
+    }
+    await tester.pumpWidget(
+      const example.MyApp(),
+    );
+
+    expect(find.byType(FloatingActionButton), findsOneWidget);
+    expect(find.byIcon(Icons.add), findsOneWidget);
+
+    final ThemeData theme = ThemeData(colorSchemeSeed: const Color(0xff6750a4), useMaterial3: true);
+    final Finder materialButtonFinder = find.byType(RawMaterialButton);
+    expect(getRawMaterialButtonWidget(materialButtonFinder).fillColor, theme.colorScheme.primaryContainer);
+    expect(getRawMaterialButtonWidget(materialButtonFinder).shape, RoundedRectangleBorder(borderRadius:  BorderRadius.circular(16.0)));
+  });
+}

examples/api/test/material/floating_action_button/floating_action_button.3_test.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_api_samples/material/floating_action_button/floating_action_button.3.dart'
+    as example;
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('FloatingActionButton variants', (WidgetTester tester) async {
+    RawMaterialButton getRawMaterialButtonWidget(Finder finder) {
+      return tester.widget<RawMaterialButton>(finder);
+    }
+
+    await tester.pumpWidget(
+      const example.MyApp(),
+    );
+
+    final ThemeData theme = ThemeData(colorSchemeSeed: const Color(0xff6750a4), useMaterial3: true);
+
+    expect(find.byType(FloatingActionButton), findsNWidgets(4));
+    expect(find.byIcon(Icons.add), findsNWidgets(4));
+
+    final Finder smallFabMaterialButton = find.byType(RawMaterialButton).at(0);
+    final RenderBox smallFabRenderBox = tester.renderObject(smallFabMaterialButton);
+    expect(smallFabRenderBox.size, const Size(48.0, 48.0));
+    expect(getRawMaterialButtonWidget(smallFabMaterialButton).fillColor, theme.colorScheme.primaryContainer);
+    expect(getRawMaterialButtonWidget(smallFabMaterialButton).shape, RoundedRectangleBorder(borderRadius:  BorderRadius.circular(12.0)));
+
+    final Finder regularFABMaterialButton = find.byType(RawMaterialButton).at(1);
+    final RenderBox regularFABRenderBox = tester.renderObject(regularFABMaterialButton);
+    expect(regularFABRenderBox.size, const Size(56.0, 56.0));
+    expect(getRawMaterialButtonWidget(regularFABMaterialButton).fillColor, theme.colorScheme.primaryContainer);
+    expect(getRawMaterialButtonWidget(regularFABMaterialButton).shape, RoundedRectangleBorder(borderRadius:  BorderRadius.circular(16.0)));
+
+    final Finder largeFABMaterialButton = find.byType(RawMaterialButton).at(2);
+    final RenderBox largeFABRenderBox = tester.renderObject(largeFABMaterialButton);
+    expect(largeFABRenderBox.size, const Size(96.0, 96.0));
+    expect(getRawMaterialButtonWidget(largeFABMaterialButton).fillColor, theme.colorScheme.primaryContainer);
+    expect(getRawMaterialButtonWidget(largeFABMaterialButton).shape, RoundedRectangleBorder(borderRadius:  BorderRadius.circular(28.0)));
+
+    final Finder extendedFABMaterialButton = find.byType(RawMaterialButton).at(3);
+    final RenderBox extendedFABRenderBox = tester.renderObject(extendedFABMaterialButton);
+    expect(extendedFABRenderBox.size, const Size(111.0, 56.0));
+    expect(getRawMaterialButtonWidget(extendedFABMaterialButton).fillColor, theme.colorScheme.primaryContainer);
+    expect(getRawMaterialButtonWidget(extendedFABMaterialButton).shape, RoundedRectangleBorder(borderRadius:  BorderRadius.circular(16.0)));
+  });
+}

packages/flutter/lib/src/material/floating_action_button.dart

@@ -69,6 +69,21 @@ enum _FloatingActionButtonType {
 /// ** See code in examples/api/lib/material/floating_action_button/floating_action_button.1.dart **
 /// {@end-tool}
 ///
+/// Material Design 3 introduced new types of floating action buttons.
+/// {@tool dartpad}
+/// This sample shows the creation of [FloatingActionButton] widget in the typical location in a Scaffold,
+/// as described in: https://m3.material.io/components/floating-action-button/overview
+///
+/// ** See code in examples/api/lib/material/floating_action_button/floating_action_button.2.dart **
+/// {@end-tool}
+///
+/// {@tool dartpad}
+/// This sample shows the creation of all the variants of [FloatingActionButton] widget as
+/// described in: https://m3.material.io/components/floating-action-button/overview
+///
+/// ** See code in examples/api/lib/material/floating_action_button/floating_action_button.3.dart **
+/// {@end-tool}
+///
 /// See also:
 ///
 ///  * [Scaffold], in which floating action buttons typically live.