Assorted a11y fixes (#14395)

examples/flutter_gallery/lib/demo/animation/widgets.dart

@@ -19,7 +19,10 @@ class SectionCard extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return new DecoratedBox(
+    return new Semantics(
+      label: section.title,
+      button: true,
+      child: new DecoratedBox(
         decoration: new BoxDecoration(
           gradient: new LinearGradient(
             begin: Alignment.centerLeft,
@@ -37,6 +40,7 @@ class SectionCard extends StatelessWidget {
           colorBlendMode: BlendMode.modulate,
           fit: BoxFit.cover,
         ),
+      ),
     );
   }
 }

examples/flutter_gallery/lib/demo/cupertino/cupertino_navigation_demo.dart

@@ -107,6 +107,7 @@ class ExitButton extends StatelessWidget {
       child: const Tooltip(
         message: 'Back',
         child: const Text('Exit'),
+        excludeFromSemantics: true,
       ),
       onPressed: () {
         // The demo is on the root navigator.

examples/flutter_gallery/lib/demo/material/buttons_demo.dart

@@ -218,14 +218,20 @@ class _ButtonsDemoState extends State<ButtonsDemo> {
         mainAxisSize: MainAxisSize.min,
         children: <Widget>[
           new IconButton(
-            icon: const Icon(Icons.thumb_up),
+            icon: const Icon(
+              Icons.thumb_up,
+              semanticLabel: 'Thumbs up',
+            ),
             onPressed: () {
               setState(() => iconButtonToggle = !iconButtonToggle);
             },
             color: iconButtonToggle ? Theme.of(context).primaryColor : null,
           ),
           const IconButton(
-            icon: const Icon(Icons.thumb_up),
+            icon: const Icon(
+              Icons.thumb_up,
+              semanticLabel: 'Thumbs up',
+            ),
             onPressed: null,
           )
         ]

examples/flutter_gallery/lib/demo/material/icons_demo.dart

@@ -108,6 +108,8 @@ class _IconsDemoCard extends StatelessWidget {
     return new Card(
       child: new DefaultTextStyle(
         style: textStyle,
+        child: new Semantics(
+          explicitChildNodes: true,
           child: new Table(
             defaultVerticalAlignment: TableCellVerticalAlignment.middle,
             children: <TableRow> [
@@ -125,6 +127,7 @@ class _IconsDemoCard extends StatelessWidget {
             ],
           ),
         ),
+      ),
     );
   }
 }

examples/flutter_gallery/lib/demo/material/persistent_bottom_sheet_demo.dart

@@ -76,7 +76,10 @@ class _PersistentBottomSheetDemoState extends State<PersistentBottomSheetDemo> {
       floatingActionButton: new FloatingActionButton(
         onPressed: _showMessage,
         backgroundColor: Colors.redAccent,
-        child: const Icon(Icons.add)
+        child: const Icon(
+          Icons.add,
+          semanticLabel: 'Add',
+        ),
       ),
       body: new Center(
         child: new RaisedButton(

examples/flutter_gallery/lib/gallery/demo.dart

@@ -154,7 +154,10 @@ class FullScreenCodeDialogState extends State<FullScreenCodeDialog> {
     return new Scaffold(
       appBar: new AppBar(
         leading: new IconButton(
-          icon: const Icon(Icons.clear),
+          icon: const Icon(
+            Icons.clear,
+            semanticLabel: 'Close',
+          ),
           onPressed: () { Navigator.pop(context); }
         ),
         title: const Text('Example code')

examples/flutter_gallery/lib/gallery/drawer.dart

@@ -52,7 +52,9 @@ class _GalleryDrawerHeaderState extends State<GalleryDrawerHeader> {
   Widget build(BuildContext context) {
     final double systemTopPadding = MediaQuery.of(context).padding.top;
 
-    return new DrawerHeader(
+    return new Semantics(
+      label: 'Flutter',
+      child: new DrawerHeader(
         decoration: new FlutterLogoDecoration(
           margin: new EdgeInsets.fromLTRB(12.0, 12.0 + systemTopPadding, 12.0, 12.0),
           style: _logoHasName ? _logoHorizontal ? FlutterLogoStyle.horizontal
@@ -96,7 +98,8 @@ class _GalleryDrawerHeaderState extends State<GalleryDrawerHeader> {
               _logoColor = options[new math.Random().nextInt(options.length)];
             });
           }
-      )
+        ),
+      ),
     );
   }
 }

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

@@ -165,12 +165,16 @@ class _FloatingActionButtonState extends State<FloatingActionButton> {
       child: new Container(
         width: widget.mini ? _kSizeMini : _kSize,
         height: widget.mini ? _kSizeMini : _kSize,
+        child: new Semantics(
+          button: true,
+          enabled: widget.onPressed != null,
           child: new InkWell(
             onTap: widget.onPressed,
             onHighlightChanged: _handleHighlightChanged,
             child: result,
           ),
         ),
+      ),
     );
 
     if (widget.heroTag != null) {

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

@@ -193,6 +193,7 @@ class IconButton extends StatelessWidget {
 
     Widget result = new Semantics(
       button: true,
+      enabled: onPressed != null,
       child: new ConstrainedBox(
         constraints: const BoxConstraints(minWidth: _kMinButtonSize, minHeight: _kMinButtonSize),
         child: new Padding(

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

@@ -48,12 +48,14 @@ class Tooltip extends StatefulWidget {
     this.padding: const EdgeInsets.symmetric(horizontal: 16.0),
     this.verticalOffset: 24.0,
     this.preferBelow: true,
+    this.excludeFromSemantics: false,
     this.child,
   }) : assert(message != null),
        assert(height != null),
        assert(padding != null),
        assert(verticalOffset != null),
        assert(preferBelow != null),
+       assert(excludeFromSemantics != null),
        super(key: key);
 
   /// The text to display in the tooltip.
@@ -77,6 +79,10 @@ class Tooltip extends StatefulWidget {
   /// direction.
   final bool preferBelow;
 
+  /// Whether the tooltip's [message] should be excluded from the semantics
+  /// tree.
+  final bool excludeFromSemantics;
+
   /// The widget below this widget in the tree.
   ///
   /// {@macro flutter.widgets.child}
@@ -191,7 +197,7 @@ class _TooltipState extends State<Tooltip> with SingleTickerProviderStateMixin {
       onLongPress: _handleLongPress,
       excludeFromSemantics: true,
       child: new Semantics(
-        label: widget.message,
+        label: widget.excludeFromSemantics ? null : widget.message,
         child: widget.child,
       ),
     );

packages/flutter/test/material/date_picker_test.dart

@@ -573,13 +573,21 @@ void _tests() {
             ],
           ),
           new TestSemantics(
-            flags: <SemanticsFlag>[SemanticsFlag.isButton],
+            flags: <SemanticsFlag>[
+              SemanticsFlag.isButton,
+              SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isEnabled,
+            ],
             actions: <SemanticsAction>[SemanticsAction.tap],
             label: r'Previous month December 2015',
             textDirection: TextDirection.ltr,
           ),
           new TestSemantics(
-            flags: <SemanticsFlag>[SemanticsFlag.isButton],
+            flags: <SemanticsFlag>[
+              SemanticsFlag.isButton,
+              SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isEnabled,
+            ],
             actions: <SemanticsAction>[SemanticsAction.tap],
             label: r'Next month February 2016',
             textDirection: TextDirection.ltr,

packages/flutter/test/material/floating_action_button_test.dart

@@ -2,9 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'dart:ui';
+
 import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
 import 'package:flutter_test/flutter_test.dart';
 
+import '../widgets/semantics_tester.dart';
+
 void main() {
   testWidgets('Floating Action Button control test', (WidgetTester tester) async {
     bool didPressButton = false;
@@ -132,4 +137,68 @@ void main() {
     await tester.pump();
     expect(tester.takeException().toString(), contains('xyzzy'));
   });
+
+  testWidgets('Floating Action Button semantics (enabled)', (WidgetTester tester) async {
+    final SemanticsTester semantics = new SemanticsTester(tester);
+
+    await tester.pumpWidget(
+      new Directionality(
+        textDirection: TextDirection.ltr,
+        child: new Center(
+          child: new FloatingActionButton(
+            onPressed: () { },
+            child: const Icon(Icons.add, semanticLabel: 'Add'),
+          ),
+        ),
+      ),
+    );
+
+    expect(semantics, hasSemantics(new TestSemantics.root(
+      children: <TestSemantics>[
+        new TestSemantics.rootChild(
+          label: 'Add',
+          flags: <SemanticsFlag>[
+            SemanticsFlag.isButton,
+            SemanticsFlag.hasEnabledState,
+            SemanticsFlag.isEnabled,
+          ],
+          actions: <SemanticsAction>[
+            SemanticsAction.tap
+          ],
+        ),
+      ],
+    ), ignoreTransform: true, ignoreId: true, ignoreRect: true));
+
+    semantics.dispose();
+  });
+
+  testWidgets('Floating Action Button semantics (disabled)', (WidgetTester tester) async {
+    final SemanticsTester semantics = new SemanticsTester(tester);
+
+    await tester.pumpWidget(
+      const Directionality(
+        textDirection: TextDirection.ltr,
+        child: const Center(
+          child: const FloatingActionButton(
+            onPressed: null,
+            child: const Icon(Icons.add, semanticLabel: 'Add'),
+          ),
+        ),
+      ),
+    );
+
+    expect(semantics, hasSemantics(new TestSemantics.root(
+      children: <TestSemantics>[
+        new TestSemantics.rootChild(
+          label: 'Add',
+          flags: <SemanticsFlag>[
+            SemanticsFlag.isButton,
+            SemanticsFlag.hasEnabledState,
+          ],
+        ),
+      ],
+    ), ignoreTransform: true, ignoreId: true, ignoreRect: true));
+
+    semantics.dispose();
+  });
 }

packages/flutter/test/material/icon_button_test.dart

@@ -275,7 +275,7 @@ void main() {
     await gesture.up();
   });
 
-  testWidgets('IconButton Semantics', (WidgetTester tester) async {
+  testWidgets('IconButton Semantics (enabled)', (WidgetTester tester) async {
     final SemanticsTester semantics = new SemanticsTester(tester);
 
     await tester.pumpWidget(
@@ -291,8 +291,42 @@ void main() {
       children: <TestSemantics>[
         new TestSemantics.rootChild(
           rect: new Rect.fromLTRB(0.0, 0.0, 48.0, 48.0),
-          actions: <SemanticsAction>[SemanticsAction.tap],
-          flags: <SemanticsFlag>[SemanticsFlag.isButton],
+          actions: <SemanticsAction>[
+            SemanticsAction.tap
+          ],
+          flags: <SemanticsFlag>[
+            SemanticsFlag.hasEnabledState,
+            SemanticsFlag.isEnabled,
+            SemanticsFlag.isButton
+          ],
+          label: 'link',
+        )
+      ]
+    ), ignoreId: true, ignoreTransform: true));
+
+    semantics.dispose();
+  });
+
+  testWidgets('IconButton Semantics (disabled)', (WidgetTester tester) async {
+    final SemanticsTester semantics = new SemanticsTester(tester);
+
+    await tester.pumpWidget(
+      wrap(
+        child: const IconButton(
+          onPressed: null,
+          icon: const Icon(Icons.link, semanticLabel: 'link'),
+        ),
+      ),
+    );
+
+    expect(semantics, hasSemantics(new TestSemantics.root(
+        children: <TestSemantics>[
+          new TestSemantics.rootChild(
+            rect: new Rect.fromLTRB(0.0, 0.0, 48.0, 48.0),
+            flags: <SemanticsFlag>[
+              SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton
+            ],
             label: 'link',
           )
         ]

packages/flutter/test/material/tooltip_test.dart

@@ -602,4 +602,57 @@ void main() {
     feedback.dispose();
   });
 
+  testWidgets('Semantics included', (WidgetTester tester) async {
+    final SemanticsTester semantics = new SemanticsTester(tester);
+
+    await tester.pumpWidget(
+      new MaterialApp(
+        home: const Center(
+          child: const Tooltip(
+            message: 'Foo',
+            child: const Text('Bar'),
+          ),
+        ),
+      ),
+    );
+
+    expect(semantics, hasSemantics(new TestSemantics.root(
+      children: <TestSemantics>[
+        new TestSemantics.rootChild(
+          label: 'Foo\nBar',
+          textDirection: TextDirection.ltr,
+        ),
+      ],
+    ), ignoreRect: true, ignoreId: true, ignoreTransform: true));
+
+    semantics.dispose();
+  });
+
+  testWidgets('Semantics excluded', (WidgetTester tester) async {
+    final SemanticsTester semantics = new SemanticsTester(tester);
+
+    await tester.pumpWidget(
+      new MaterialApp(
+        home: const Center(
+          child: const Tooltip(
+            message: 'Foo',
+            child: const Text('Bar'),
+            excludeFromSemantics: true,
+          ),
+        ),
+      ),
+    );
+
+    expect(semantics, hasSemantics(new TestSemantics.root(
+      children: <TestSemantics>[
+        new TestSemantics.rootChild(
+          label: 'Bar',
+          textDirection: TextDirection.ltr,
+        ),
+      ],
+    ), ignoreRect: true, ignoreId: true, ignoreTransform: true));
+
+    semantics.dispose();
+  });
+
 }