Enables setting of semantics focused and focusable attributes within Focus widgets. (#41814)

This adds a Semantics node to the Focus and FocusScope widgets, setting the focused and focusable attributes so that the accessibility subsystem can be told when a control has the input focus.

Includes an engine roll to flutter/engine@77252d2, and the following 8 engine changes:

flutter/engine@77252d2 Greg Spencer Add missing focusable testing info (flutter/engine#13013)
flutter/engine@0e42a29 skia-flutter-.. Roll src/third_party/skia 54548626a977..e27a503a0a21 (1 commits) (flutter/engine#13024)
flutter/engine@6b56ed7 gaaclarke Refactor: FlutterDartProject (flutter/engine#13006)
flutter/engine@393480c skia-flutter-.. Roll src/third_party/skia 77dde599c98a..54548626a977 (1 commits) (flutter/engine#13023)
flutter/engine@080b89d skia-flutter-.. Roll src/third_party/skia 2b1a25a4d324..77dde599c98a (1 commits) (flutter/engine#13021)
flutter/engine@90b0f30 Ben Konyi Roll src/third_party/dart f4a72bfc64..bb04f145b2 (18 commits) (flutter/engine#13020)
flutter/engine@049fb89 skia-flutter-.. Roll fuchsia/sdk/core/linux-amd64 from q_uYX... to cknsi... (flutter/engine#13019)
flutter/engine@6925b2a skia-flutter-.. Roll fuchsia/sdk/core/mac-amd64 from wuAtw... to u0JpE... (flutter/engine#13018)

Related Issues
Addresses #40101

Landing on red in order to fix the build: it's red because of the needed engine roll.

bin/internal/engine.version

-0d749933bcc63b53771e37e6cc28fa43c3d1fd06
+77252d2371f3341f9f3a7e3ec2eb64bfa29bf975

dev/integration_tests/android_semantics_testing/lib/main.dart

@@ -11,6 +11,8 @@ import 'package:flutter/services.dart';
 import 'package:flutter_driver/driver_extension.dart';
 
 import 'src/tests/controls_page.dart';
+import 'src/tests/popup_constants.dart';
+import 'src/tests/popup_page.dart';
 import 'src/tests/text_field_page.dart';
 
 void main() {
@@ -40,10 +42,11 @@ Future<String> dataHandler(String message) async {
   throw UnimplementedError();
 }
 
-const List<String> routes = <String>[
-  selectionControlsRoute,
-  textFieldRoute,
-];
+Map<String, WidgetBuilder> routes = <String, WidgetBuilder>{
+  selectionControlsRoute : (BuildContext context) => SelectionControlsPage(),
+  popupControlsRoute : (BuildContext context) => PopupControlsPage(),
+  textFieldRoute : (BuildContext context) => TextFieldPage(),
+};
 
 class TestApp extends StatelessWidget {
   const TestApp();
@@ -51,15 +54,12 @@ class TestApp extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
-      routes: <String, WidgetBuilder>{
-        selectionControlsRoute: (BuildContext context) => SelectionControlsPage(),
-        textFieldRoute: (BuildContext context) => TextFieldPage(),
-      },
+      routes: routes,
       home: Builder(
         builder: (BuildContext context) {
           return Scaffold(
             body: ListView(
-              children: routes.map<Widget>((String value) {
+              children: routes.keys.map<Widget>((String value) {
                 return MaterialButton(
                   child: Text(value),
                   onPressed: () {

dev/integration_tests/android_semantics_testing/lib/src/constants.dart

@@ -24,6 +24,9 @@ class AndroidClassName {
 
   /// The class name used for toggle switches.
   static const String toggleSwitch = 'android.widget.Switch';
+
+  /// The default className for buttons.
+  static const String button = 'android.widget.Button';
 }
 
 /// Action constants which correspond to `AccessibilityAction` in Android.

dev/integration_tests/android_semantics_testing/lib/src/matcher.dart

@@ -135,8 +135,13 @@ class _AndroidSemanticsMatcher extends Matcher {
       return _failWithMessage('Expected size: $size', matchState);
     if (actions != null) {
       final List<AndroidSemanticsAction> itemActions = item.getActions();
-      if (!unorderedEquals(actions).matches(itemActions, matchState))
-        return _failWithMessage('Expected actions: $actions', matchState);
+      if (!unorderedEquals(actions).matches(itemActions, matchState)) {
+        final List<String> actionsString = actions.map<String>((AndroidSemanticsAction action) => action.toString()).toList()..sort();
+        final List<String> itemActionsString = itemActions.map<String>((AndroidSemanticsAction action) => action.toString()).toList()..sort();
+        final Set<String> unexpected = itemActionsString.toSet().difference(actionsString.toSet());
+        final Set<String> missing = actionsString.toSet().difference(itemActionsString.toSet());
+        return _failWithMessage('Expected actions: $actionsString\nActual actions: $itemActionsString\nUnexpected: $unexpected\nMissing: $missing', matchState);
+      }
     }
     if (isChecked != null && isChecked != item.isChecked)
       return _failWithMessage('Expected isChecked: $isChecked', matchState);

dev/integration_tests/android_semantics_testing/lib/src/tests/popup_constants.dart

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/// The name of the route containing the test suite.
+const String popupControlsRoute = 'popups';
+
+/// The string supplied to the [ValueKey] for the popup menu button.
+const String popupButtonKeyValue = 'PopupControls#PopupButton1';
+
+/// The string supplied to the [ValueKey] for the popup menu.
+const String popupKeyValue = 'PopupControls#Popup1';
+
+/// The string supplied to the [ValueKey] for the dropdown button.
+const String dropdownButtonKeyValue = 'PopupControls#DropdownButton1';
+
+/// The string supplied to the [ValueKey] for the dropdown button menu.
+const String dropdownKeyValue = 'PopupControls#Dropdown1';
+
+/// The string supplied to the [ValueKey] for the alert button.
+const String alertButtonKeyValue = 'PopupControls#AlertButton1';
+
+/// The string supplied to the [ValueKey] for the alert dialog.
+const String alertKeyValue = 'PopupControls#Alert1';
+
+const List<String> popupItems = <String>['Item 1', 'Item 2', 'Item 3', 'Item 4', 'Item 5'];

dev/integration_tests/android_semantics_testing/lib/src/tests/popup_page.dart

+// Copyright 2018 The Chromium 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 'popup_constants.dart';
+
+export 'popup_constants.dart';
+
+/// A page with a popup menu, a dropdown menu, and a modal alert.
+class PopupControlsPage extends StatefulWidget {
+  @override
+  State<StatefulWidget> createState() => _PopupControlsPageState();
+}
+
+class _PopupControlsPageState extends State<PopupControlsPage> {
+  final Key popupKey = const ValueKey<String>(popupKeyValue);
+  final Key dropdownKey = const ValueKey<String>(dropdownKeyValue);
+  final Key alertKey = const ValueKey<String>(alertKeyValue);
+
+  String popupValue = popupItems.first;
+  String dropdownValue = popupItems.first;
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(leading: const BackButton(key: ValueKey<String>('back'))),
+      body: SafeArea(
+        child: Center(
+          child: Row(
+            mainAxisAlignment: MainAxisAlignment.center,
+            mainAxisSize: MainAxisSize.min,
+            children: <Widget>[
+              PopupMenuButton<String>(
+                key: const ValueKey<String>(popupButtonKeyValue),
+                icon: const Icon(Icons.arrow_drop_down),
+                itemBuilder: (BuildContext context) {
+                  return popupItems.map<PopupMenuItem<String>>((String item) {
+                    return PopupMenuItem<String>(
+                      key: ValueKey<String>('$popupKeyValue.$item'),
+                      value: item,
+                      child: Text(item),
+                    );
+                  }).toList();
+                },
+                onSelected: (String value) {
+                  popupValue = value;
+                },
+              ),
+              DropdownButton<String>(
+                key: const ValueKey<String>(dropdownButtonKeyValue),
+                value: dropdownValue,
+                items: popupItems.map<DropdownMenuItem<String>>((String item) {
+                  return DropdownMenuItem<String>(
+                    key: ValueKey<String>('$dropdownKeyValue.$item'),
+                    value: item,
+                    child: Text(item),
+                  );
+                }).toList(),
+                onChanged: (String value) {
+                  setState(() {
+                    dropdownValue = value;
+                  });
+                },
+              ),
+              MaterialButton(
+                key: const ValueKey<String>(alertButtonKeyValue),
+                child: const Text('Alert'),
+                onPressed: () {
+                  showDialog<void>(
+                    context: context,
+                    barrierDismissible: false, // user must tap button!
+                    builder: (BuildContext context) {
+                      return AlertDialog(
+                        key: const ValueKey<String>(alertKeyValue),
+                        title: const Text('Title text', key: ValueKey<String>('$alertKeyValue.Title')),
+                        content: SingleChildScrollView(
+                          child: ListBody(
+                            children: const <Widget>[
+                              Text('Body text line 1.', key: ValueKey<String>('$alertKeyValue.Body1')),
+                              Text('Body text line 2.', key: ValueKey<String>('$alertKeyValue.Body2')),
+                            ],
+                          ),
+                        ),
+                        actions: <Widget>[
+                          FlatButton(
+                            child: const Text('OK', key: ValueKey<String>('$alertKeyValue.OK')),
+                            onPressed: () {
+                              Navigator.of(context).pop();
+                            },
+                          ),
+                        ],
+                      );
+                    },
+                  );
+                },
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}

dev/integration_tests/android_semantics_testing/lib/test_constants.dart

@@ -3,4 +3,5 @@
 // found in the LICENSE file.
 
 export 'src/tests/controls_constants.dart';
+export 'src/tests/popup_constants.dart';
 export 'src/tests/text_field_constants.dart';

examples/flutter_gallery/test/demo/material/chip_demo_test.dart

@@ -18,6 +18,7 @@ void main() {
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       hasTapAction: true,
       label: 'Update border shape',
     ));
@@ -26,6 +27,7 @@ void main() {
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       hasTapAction: true,
       label: 'Reset chips',
     ));

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

@@ -723,7 +723,7 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
     } else {
       // For the sake of backwards compatibility. An (unlikely) app that relied
       // on having menus only inherit from the material Theme could set
-      // captureInheritedThemes to false and get the original behvaior.
+      // captureInheritedThemes to false and get the original behavior.
       if (theme != null)
         menu = Theme(data: theme, child: menu);
     }

packages/flutter/lib/src/rendering/custom_paint.dart

@@ -840,6 +840,9 @@ class RenderCustomPaint extends RenderProxyBox {
     if (properties.readOnly != null) {
       config.isReadOnly = properties.readOnly;
     }
+    if (properties.focusable != null) {
+      config.isFocusable = properties.focusable;
+    }
     if (properties.focused != null) {
       config.isFocused = properties.focused;
     }

packages/flutter/lib/src/rendering/proxy_box.dart

@@ -3489,6 +3489,7 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
     bool header,
     bool textField,
     bool readOnly,
+    bool focusable,
     bool focused,
     bool inMutuallyExclusiveGroup,
     bool obscured,
@@ -3541,6 +3542,7 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
        _header = header,
        _textField = textField,
        _readOnly = readOnly,
+       _focusable = focusable,
        _focused = focused,
        _inMutuallyExclusiveGroup = inMutuallyExclusiveGroup,
        _obscured = obscured,
@@ -3720,6 +3722,16 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
     markNeedsSemanticsUpdate();
   }
 
+  /// If non-null, sets the [SemanticsNode.isFocusable] semantic to the given value.
+  bool get focusable => _focusable;
+  bool _focusable;
+  set focusable(bool value) {
+    if (focusable == value)
+      return;
+    _focusable = value;
+    markNeedsSemanticsUpdate();
+  }
+
   /// If non-null, sets the [SemanticsNode.isFocused] semantic to the given value.
   bool get focused => _focused;
   bool _focused;
@@ -4380,6 +4392,8 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
       config.isTextField = textField;
     if (readOnly != null)
       config.isReadOnly = readOnly;
+    if (focusable != null)
+      config.isFocusable = focusable;
     if (focused != null)
       config.isFocused = focused;
     if (inMutuallyExclusiveGroup != null)

packages/flutter/lib/src/semantics/semantics.dart

@@ -595,6 +595,7 @@ class SemanticsProperties extends DiagnosticableTree {
     this.header,
     this.textField,
     this.readOnly,
+    this.focusable,
     this.focused,
     this.inMutuallyExclusiveGroup,
     this.hidden,
@@ -698,14 +699,25 @@ class SemanticsProperties extends DiagnosticableTree {
   /// TalkBack/VoiceOver will treat it as non-editable text field.
   final bool readOnly;
 
+  /// If non-null, whether the node is able to hold input focus.
+  ///
+  /// If [focusable] is set to false, then [focused] must not be true.
+  ///
+  /// Input focus indicates that the node will receive keyboard events. It is not
+  /// to be confused with accessibility focus. Accessibility focus is the
+  /// green/black rectangular highlight that TalkBack/VoiceOver draws around the
+  /// element it is reading, and is separate from input focus.
+  final bool focusable;
+
   /// If non-null, whether the node currently holds input focus.
   ///
-  /// At most one node in the tree should hold input focus at any point in time.
+  /// At most one node in the tree should hold input focus at any point in time,
+  /// and it should not be set to true if [focusable] is false.
   ///
-  /// Input focus (indicates that the node will receive keyboard events) is not
+  /// Input focus indicates that the node will receive keyboard events. It is not
   /// to be confused with accessibility focus. Accessibility focus is the
-  /// green/black rectangular that TalkBack/VoiceOver on the screen and is
-  /// separate from input focus.
+  /// green/black rectangular highlight that TalkBack/VoiceOver draws around the
+  /// element it is reading, and is separate from input focus.
   final bool focused;
 
   /// If non-null, whether a semantic node is in a mutually exclusive group.
@@ -3611,7 +3623,13 @@ class SemanticsConfiguration {
     _setFlag(SemanticsFlag.isInMutuallyExclusiveGroup, value);
   }
 
-  /// Whether the owning [RenderObject] currently holds the user's focus.
+  /// Whether the owning [RenderObject] can hold the input focus.
+  bool get isFocusable => _hasFlag(SemanticsFlag.isFocusable);
+  set isFocusable(bool value) {
+    _setFlag(SemanticsFlag.isFocusable, value);
+  }
+
+  /// Whether the owning [RenderObject] currently holds the input focus.
   bool get isFocused => _hasFlag(SemanticsFlag.isFocused);
   set isFocused(bool value) {
     _setFlag(SemanticsFlag.isFocused, value);

packages/flutter/lib/src/widgets/basic.dart

@@ -6188,6 +6188,7 @@ class Semantics extends SingleChildRenderObjectWidget {
     bool header,
     bool textField,
     bool readOnly,
+    bool focusable,
     bool focused,
     bool inMutuallyExclusiveGroup,
     bool obscured,
@@ -6242,6 +6243,7 @@ class Semantics extends SingleChildRenderObjectWidget {
       header: header,
       textField: textField,
       readOnly: readOnly,
+      focusable: focusable,
       focused: focused,
       inMutuallyExclusiveGroup: inMutuallyExclusiveGroup,
       obscured: obscured,
@@ -6355,6 +6357,7 @@ class Semantics extends SingleChildRenderObjectWidget {
       header: properties.header,
       textField: properties.textField,
       readOnly: properties.readOnly,
+      focusable: properties.focusable,
       focused: properties.focused,
       liveRegion: properties.liveRegion,
       maxValueLength: properties.maxValueLength,
@@ -6425,6 +6428,7 @@ class Semantics extends SingleChildRenderObjectWidget {
       ..header = properties.header
       ..textField = properties.textField
       ..readOnly = properties.readOnly
+      ..focusable = properties.focusable
       ..focused = properties.focused
       ..inMutuallyExclusiveGroup = properties.inMutuallyExclusiveGroup
       ..obscured = properties.obscured

packages/flutter/lib/src/widgets/focus_scope.dart

@@ -137,7 +137,7 @@ class Focus extends StatefulWidget {
   ///
   /// The [child] argument is required and must not be null.
   ///
-  /// The [autofocus] and [skipTraversal] arguments must not be null.
+  /// The [autofocus] argument must not be null.
   const Focus({
     Key key,
     @required this.child,
@@ -323,6 +323,8 @@ class _FocusState extends State<Focus> {
   FocusNode _internalNode;
   FocusNode get focusNode => widget.focusNode ?? _internalNode;
   bool _hasFocus;
+  bool _hasPrimaryFocus;
+  bool _canRequestFocus;
   bool _didAutofocus = false;
   FocusAttachment _focusAttachment;
 
@@ -343,6 +345,8 @@ class _FocusState extends State<Focus> {
     focusNode.skipTraversal = widget.skipTraversal ?? focusNode.skipTraversal;
     focusNode.canRequestFocus = widget.canRequestFocus ?? focusNode.canRequestFocus;
     _hasFocus = focusNode.hasFocus;
+    _canRequestFocus = focusNode.canRequestFocus;
+    _hasPrimaryFocus = focusNode.hasPrimaryFocus;
 
     // Add listener even if the _internalNode existed before, since it should
     // not be listening now if we're re-using a previous one because it should
@@ -426,6 +430,16 @@ class _FocusState extends State<Focus> {
         widget.onFocusChange(focusNode.hasFocus);
       }
     }
+    if (_hasPrimaryFocus != focusNode.hasPrimaryFocus) {
+      setState(() {
+        _hasPrimaryFocus = focusNode.hasPrimaryFocus;
+      });
+    }
+    if (_canRequestFocus != focusNode.canRequestFocus) {
+      setState(() {
+        _canRequestFocus = focusNode.canRequestFocus;
+      });
+    }
   }
 
   @override
@@ -433,7 +447,11 @@ class _FocusState extends State<Focus> {
     _focusAttachment.reparent();
     return _FocusMarker(
       node: focusNode,
-      child: widget.child,
+      child: Semantics(
+        focusable: _canRequestFocus,
+        focused: _hasPrimaryFocus,
+        child: widget.child,
+      ),
     );
   }
 }

packages/flutter/test/material/back_button_test.dart

@@ -119,6 +119,7 @@ void main() {
       hasEnabledState: true,
       isEnabled: true,
       hasTapAction: true,
+      isFocusable: true,
     ));
     handle.dispose();
   });

packages/flutter/test/material/bottom_navigation_bar_test.dart

@@ -1191,6 +1191,7 @@ void main() {
               children: <TestSemantics>[
                 TestSemantics(
                   flags: <SemanticsFlag>[
+                    SemanticsFlag.isFocusable,
                     SemanticsFlag.isSelected,
                   ],
                   actions: <SemanticsAction>[SemanticsAction.tap],
@@ -1198,11 +1199,13 @@ void main() {
                   textDirection: TextDirection.ltr,
                 ),
                 TestSemantics(
+                  flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Alarm\nTab 2 of 3',
                   textDirection: TextDirection.ltr,
                 ),
                 TestSemantics(
+                  flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Hot Tub\nTab 3 of 3',
                   textDirection: TextDirection.ltr,
@@ -1252,6 +1255,7 @@ void main() {
               children: <TestSemantics>[
                 TestSemantics(
                   flags: <SemanticsFlag>[
+                    SemanticsFlag.isFocusable,
                     SemanticsFlag.isSelected,
                   ],
                   actions: <SemanticsAction>[SemanticsAction.tap],
@@ -1259,11 +1263,13 @@ void main() {
                   textDirection: TextDirection.ltr,
                 ),
                 TestSemantics(
+                  flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Alarm\nTab 2 of 3',
                   textDirection: TextDirection.ltr,
                 ),
                 TestSemantics(
+                  flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Hot Tub\nTab 3 of 3',
                   textDirection: TextDirection.ltr,
@@ -1553,6 +1559,7 @@ void main() {
               children: <TestSemantics>[
                 TestSemantics(
                   flags: <SemanticsFlag>[
+                    SemanticsFlag.isFocusable,
                     SemanticsFlag.isSelected,
                   ],
                   actions: <SemanticsAction>[SemanticsAction.tap],
@@ -1560,6 +1567,7 @@ void main() {
                   textDirection: TextDirection.ltr,
                 ),
                 TestSemantics(
+                  flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Green\nTab 2 of 2',
                   textDirection: TextDirection.ltr,
@@ -1608,12 +1616,14 @@ void main() {
                 TestSemantics(
                   flags: <SemanticsFlag>[
                     SemanticsFlag.isSelected,
+                    SemanticsFlag.isFocusable,
                   ],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Red\nTab 1 of 2',
                   textDirection: TextDirection.ltr,
                 ),
                 TestSemantics(
+                  flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                   actions: <SemanticsAction>[SemanticsAction.tap],
                   label: 'Green\nTab 2 of 2',
                   textDirection: TextDirection.ltr,

packages/flutter/test/material/buttons_test.dart

@@ -565,9 +565,10 @@ void main() {
             rect: const Rect.fromLTRB(0.0, 0.0, 88.0, 48.0),
             transform: Matrix4.translationValues(356.0, 276.0, 0.0),
             flags: <SemanticsFlag>[
-              SemanticsFlag.isButton,
               SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton,
               SemanticsFlag.isEnabled,
+              SemanticsFlag.isFocusable,
             ],
           ),
         ],
@@ -605,9 +606,10 @@ void main() {
             rect: const Rect.fromLTRB(0.0, 0.0, 88.0, 48.0),
             transform: Matrix4.translationValues(356.0, 276.0, 0.0),
             flags: <SemanticsFlag>[
-              SemanticsFlag.isButton,
               SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton,
               SemanticsFlag.isEnabled,
+              SemanticsFlag.isFocusable,
             ],
           ),
         ],
@@ -889,9 +891,10 @@ void main() {
               SemanticsAction.tap,
             ],
             flags: <SemanticsFlag>[
-              SemanticsFlag.isButton,
               SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton,
               SemanticsFlag.isEnabled,
+              SemanticsFlag.isFocusable,
             ],
           ),
         ],
@@ -920,8 +923,9 @@ void main() {
             transform: expectedButtonTransform,
             label: 'Button',
             flags: <SemanticsFlag>[
-              SemanticsFlag.isButton,
               SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton,
+              SemanticsFlag.isFocusable,
             ],
           ),
         ],

packages/flutter/test/material/card_test.dart

@@ -62,9 +62,10 @@ void main() {
                   SemanticsAction.tap,
                 ],
                 flags: <SemanticsFlag>[
-                  SemanticsFlag.isButton,
                   SemanticsFlag.hasEnabledState,
+                  SemanticsFlag.isButton,
                   SemanticsFlag.isEnabled,
+                  SemanticsFlag.isFocusable,
                 ],
               ),
             ],

packages/flutter/test/material/chip_test.dart

@@ -1353,6 +1353,7 @@ void main() {
                       TestSemantics(
                         label: 'test',
                         textDirection: TextDirection.ltr,
+                        flags: <SemanticsFlag>[SemanticsFlag.isFocusable],
                       ),
                     ],
                   ),
@@ -1390,6 +1391,7 @@ void main() {
                         flags: <SemanticsFlag>[
                           SemanticsFlag.hasEnabledState,
                           SemanticsFlag.isEnabled,
+                          SemanticsFlag.isFocusable,
                         ],
                         actions: <SemanticsAction>[SemanticsAction.tap],
                       ),
@@ -1436,6 +1438,7 @@ void main() {
                         flags: <SemanticsFlag>[
                           SemanticsFlag.hasEnabledState,
                           SemanticsFlag.isEnabled,
+                          SemanticsFlag.isFocusable,
                         ],
                         actions: <SemanticsAction>[SemanticsAction.tap],
                       ),
@@ -1474,9 +1477,10 @@ void main() {
                         label: 'test',
                         textDirection: TextDirection.ltr,
                         flags: <SemanticsFlag>[
-                          SemanticsFlag.isSelected,
                           SemanticsFlag.hasEnabledState,
                           SemanticsFlag.isEnabled,
+                          SemanticsFlag.isFocusable,
+                          SemanticsFlag.isSelected,
                         ],
                         actions: <SemanticsAction>[SemanticsAction.tap],
                       ),

packages/flutter/test/material/date_picker_test.dart

@@ -636,25 +636,45 @@ void _tests() {
                 ],
               ),
               TestSemantics(
-                flags: <SemanticsFlag>[SemanticsFlag.isButton, SemanticsFlag.hasEnabledState, SemanticsFlag.isEnabled],
+                flags: <SemanticsFlag>[
+                  SemanticsFlag.hasEnabledState,
+                  SemanticsFlag.isButton,
+                  SemanticsFlag.isEnabled,
+                  SemanticsFlag.isFocusable,
+                ],
                 actions: <SemanticsAction>[SemanticsAction.tap],
                 label: 'Previous month December 2015',
                 textDirection: TextDirection.ltr,
               ),
               TestSemantics(
-                flags: <SemanticsFlag>[SemanticsFlag.isButton, SemanticsFlag.hasEnabledState, SemanticsFlag.isEnabled],
+                flags: <SemanticsFlag>[
+                  SemanticsFlag.hasEnabledState,
+                  SemanticsFlag.isButton,
+                  SemanticsFlag.isEnabled,
+                  SemanticsFlag.isFocusable,
+                ],
                 actions: <SemanticsAction>[SemanticsAction.tap],
                 label: 'Next month February 2016',
                 textDirection: TextDirection.ltr,
               ),
               TestSemantics(
-                flags: <SemanticsFlag>[SemanticsFlag.isButton, SemanticsFlag.hasEnabledState, SemanticsFlag.isEnabled],
+                flags: <SemanticsFlag>[
+                  SemanticsFlag.hasEnabledState,
+                  SemanticsFlag.isButton,
+                  SemanticsFlag.isEnabled,
+                  SemanticsFlag.isFocusable,
+                ],
                 actions: <SemanticsAction>[SemanticsAction.tap],
                 label: 'CANCEL',
                 textDirection: TextDirection.ltr,
               ),
               TestSemantics(
-                flags: <SemanticsFlag>[SemanticsFlag.isButton, SemanticsFlag.hasEnabledState, SemanticsFlag.isEnabled],
+                flags: <SemanticsFlag>[
+                  SemanticsFlag.hasEnabledState,
+                  SemanticsFlag.isButton,
+                  SemanticsFlag.isEnabled,
+                  SemanticsFlag.isFocusable,
+                ],
                 actions: <SemanticsAction>[SemanticsAction.tap],
                 label: 'OK',
                 textDirection: TextDirection.ltr,

packages/flutter/test/material/expand_icon_test.dart

@@ -148,6 +148,7 @@ void main() {
       hasTapAction: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       isButton: true,
       onTapHint: localizations.expandedIconTapHint,
     ));
@@ -163,6 +164,7 @@ void main() {
       hasTapAction: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       isButton: true,
       onTapHint: localizations.collapsedIconTapHint,
     ));

packages/flutter/test/material/expansion_panel_test.dart

@@ -194,6 +194,7 @@ void main() {
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       hasTapAction: true,
     ));
 
@@ -937,6 +938,7 @@ void main() {
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       hasTapAction: true,
       onTapHint: localizations.expandedIconTapHint,
     ));
@@ -960,6 +962,7 @@ void main() {
       isButton: true,
       hasEnabledState: true,
       isEnabled: true,
+      isFocusable: true,
       hasTapAction: true,
       onTapHint: localizations.collapsedIconTapHint,
     ));

packages/flutter/test/material/floating_action_button_test.dart

@@ -560,9 +560,10 @@ void main() {
         TestSemantics.rootChild(
           label: 'Add',
           flags: <SemanticsFlag>[
-            SemanticsFlag.isButton,
             SemanticsFlag.hasEnabledState,
+            SemanticsFlag.isButton,
             SemanticsFlag.isEnabled,
+            SemanticsFlag.isFocusable,
           ],
           actions: <SemanticsAction>[
             SemanticsAction.tap,
@@ -634,9 +635,10 @@ void main() {
                     SemanticsAction.tap,
                   ],
                   flags: <SemanticsFlag>[
-                    SemanticsFlag.isButton,
                     SemanticsFlag.hasEnabledState,
+                    SemanticsFlag.isButton,
                     SemanticsFlag.isEnabled,
+                    SemanticsFlag.isFocusable,
                   ],
                 ),
               ],
@@ -780,6 +782,7 @@ void main() {
         hasEnabledState: true,
         isButton: true,
         isEnabled: true,
+        isFocusable: true,
       ),
     );
   }, semanticsEnabled: true);

packages/flutter/test/material/icon_button_test.dart

@@ -294,8 +294,9 @@ void main() {
           ],
           flags: <SemanticsFlag>[
             SemanticsFlag.hasEnabledState,
-            SemanticsFlag.isEnabled,
             SemanticsFlag.isButton,
+            SemanticsFlag.isEnabled,
+            SemanticsFlag.isFocusable,
           ],
           label: 'link',
         ),

packages/flutter/test/material/outline_button_test.dart

@@ -666,9 +666,10 @@ void main() {
             rect: const Rect.fromLTRB(0.0, 0.0, 88.0, 48.0),
             transform: Matrix4.translationValues(356.0, 276.0, 0.0),
             flags: <SemanticsFlag>[
-              SemanticsFlag.isButton,
               SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton,
               SemanticsFlag.isEnabled,
+              SemanticsFlag.isFocusable,
             ],
           ),
         ],

packages/flutter/test/material/raw_material_button_test.dart

@@ -55,9 +55,10 @@ void main() {
           TestSemantics(
             id: 1,
             flags: <SemanticsFlag>[
-              SemanticsFlag.isButton,
               SemanticsFlag.hasEnabledState,
+              SemanticsFlag.isButton,
               SemanticsFlag.isEnabled,
+              SemanticsFlag.isFocusable,
             ],
             actions: <SemanticsAction>[
               SemanticsAction.tap,

packages/flutter/test/material/search_test.dart

@@ -558,9 +558,10 @@ void main() {
                       TestSemantics(
                         id: 10,
                         flags: <SemanticsFlag>[
-                          SemanticsFlag.isButton,
                           SemanticsFlag.hasEnabledState,
+                          SemanticsFlag.isButton,
                           SemanticsFlag.isEnabled,
+                          SemanticsFlag.isFocusable,
                         ],
                         actions: <SemanticsAction>[SemanticsAction.tap],
                         label: 'Back',
@@ -588,9 +589,10 @@ void main() {
                   TestSemantics(
                     id: 8,
                     flags: <SemanticsFlag>[
-                      SemanticsFlag.isButton,
                       SemanticsFlag.hasEnabledState,
+                      SemanticsFlag.isButton,
                       SemanticsFlag.isEnabled,
+                      SemanticsFlag.isFocusable,
                     ],
                     actions: <SemanticsAction>[SemanticsAction.tap],
                     label: 'Suggestions',

packages/flutter/test/widgets/custom_painter_test.dart

@@ -417,6 +417,7 @@ void _defineTests() {
             textField: true,
             readOnly: true,
             focused: true,
+            focusable: true,
             inMutuallyExclusiveGroup: true,
             header: true,
             obscured: true,
@@ -431,6 +432,7 @@ void _defineTests() {
       ),
     ));
     List<SemanticsFlag> flags = SemanticsFlag.values.values.toList();
+    print('flags: $flags');
     // [SemanticsFlag.hasImplicitScrolling] isn't part of [SemanticsProperties]
     // therefore it has to be removed.
     flags.remove(SemanticsFlag.hasImplicitScrolling);
@@ -466,6 +468,7 @@ void _defineTests() {
             textField: true,
             readOnly: true,
             focused: true,
+            focusable: true,
             inMutuallyExclusiveGroup: true,
             header: true,
             obscured: true,
@@ -482,7 +485,6 @@ void _defineTests() {
     // [SemanticsFlag.hasImplicitScrolling] isn't part of [SemanticsProperties]
     // therefore it has to be removed.
     flags.remove(SemanticsFlag.hasImplicitScrolling);
-
     expectedSemantics = TestSemantics.root(
       children: <TestSemantics>[
         TestSemantics.rootChild(

packages/flutter/test/widgets/focus_scope_test.dart

@@ -2,8 +2,11 @@
 // 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_test/flutter_test.dart';
 import 'package:flutter/widgets.dart';
+import 'package:flutter/semantics.dart';
 
 class TestFocus extends StatefulWidget {
   const TestFocus({
@@ -24,6 +27,7 @@ class TestFocus extends StatefulWidget {
 class TestFocusState extends State<TestFocus> {
   FocusNode focusNode;
   String _label;
+  bool built = false;
 
   @override
   void dispose() {
@@ -50,6 +54,7 @@ class TestFocusState extends State<TestFocus> {
 
   @override
   Widget build(BuildContext context) {
+    built = true;
     return GestureDetector(
       onTap: () {
         FocusScope.of(context).requestFocus(focusNode);
@@ -1290,4 +1295,48 @@ void main() {
 
     expect(WidgetsBinding.instance.focusManager.rootScope.descendants, isEmpty);
   });
+  testWidgets('Focus widgets set Semantics information about focus', (WidgetTester tester) async {
+    final GlobalKey<TestFocusState> key = GlobalKey();
+
+    await tester.pumpWidget(
+      TestFocus(key: key, name: 'a'),
+    );
+
+    final SemanticsNode semantics = tester.getSemantics(find.byKey(key));
+
+    expect(key.currentState.focusNode.hasFocus, isFalse);
+    expect(semantics.hasFlag(SemanticsFlag.isFocused), isFalse);
+    expect(semantics.hasFlag(SemanticsFlag.isFocusable), isTrue);
+
+    FocusScope.of(key.currentContext).requestFocus(key.currentState.focusNode);
+    await tester.pumpAndSettle();
+
+    expect(key.currentState.focusNode.hasFocus, isTrue);
+    expect(semantics.hasFlag(SemanticsFlag.isFocused), isTrue);
+    expect(semantics.hasFlag(SemanticsFlag.isFocusable), isTrue);
+
+    key.currentState.focusNode.canRequestFocus = false;
+    await tester.pumpAndSettle();
+
+    expect(key.currentState.focusNode.hasFocus, isFalse);
+    expect(key.currentState.focusNode.canRequestFocus, isFalse);
+    expect(semantics.hasFlag(SemanticsFlag.isFocused), isFalse);
+    expect(semantics.hasFlag(SemanticsFlag.isFocusable), isFalse);
+  });
+  testWidgets('Setting canRequestFocus on focus node causes update.', (WidgetTester tester) async {
+    final GlobalKey<TestFocusState> key = GlobalKey();
+
+    final TestFocus testFocus = TestFocus(key: key, name: 'a');
+    await tester.pumpWidget(
+      testFocus,
+    );
+
+    await tester.pumpAndSettle();
+    key.currentState.built = false;
+    key.currentState.focusNode.canRequestFocus = false;
+    await tester.pumpAndSettle();
+    key.currentState.built = true;
+
+    expect(key.currentState.focusNode.canRequestFocus, isFalse);
+  });
 }

packages/flutter/test/widgets/platform_view_test.dart

@@ -4,6 +4,7 @@
 @TestOn('!chrome')
 import 'dart:async';
 import 'dart:typed_data';
+import 'dart:ui';
 
 import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
@@ -836,7 +837,15 @@ void main() {
         ),
       );
 
-      final SemanticsNode semantics =  tester.getSemantics(find.byType(AndroidView));
+      // Find the first _AndroidPlatformView widget inside of the AndroidView so
+      // that it finds the right RenderObject when looking for semantics.
+      final Finder semanticsFinder = find.byWidgetPredicate(
+            (Widget widget) {
+          return widget.runtimeType.toString() == '_AndroidPlatformView';
+        },
+        description: '_AndroidPlatformView widget inside AndroidView',
+      );
+      final SemanticsNode semantics = tester.getSemantics(semanticsFinder.first);
 
       // Platform view has not been created yet, no platformViewId.
       expect(semantics.platformViewId, null);

packages/flutter/test/widgets/semantics_test.dart

@@ -477,6 +477,7 @@ void main() {
           textField: true,
           readOnly: true,
           focused: true,
+          focusable: true,
           inMutuallyExclusiveGroup: true,
           header: true,
           obscured: true,

packages/flutter_driver/lib/src/extension/extension.dart

@@ -428,7 +428,11 @@ class FlutterDriverExtension {
   Future<GetSemanticsIdResult> _getSemanticsId(Command command) async {
     final GetSemanticsId semanticsCommand = command;
     final Finder target = await _waitForElement(_createFinder(semanticsCommand.finder));
-    final Element element = target.evaluate().single;
+    final Iterable<Element> elements = target.evaluate();
+    if (elements.length > 1) {
+      throw StateError('Found more than one element with the same ID: $elements');
+    }
+    final Element element = elements.single;
     RenderObject renderObject = element.renderObject;
     SemanticsNode node;
     while (renderObject != null && node == null) {

packages/flutter_driver/test/src/extension_test.dart

@@ -494,7 +494,7 @@ void main() {
       final Map<String, Object> response = await extension.call(arguments);
 
       expect(response['isError'], true);
-      expect(response['response'], contains('Bad state: Too many elements'));
+      expect(response['response'], contains('Bad state: Found more than one element with the same ID'));
       semantics.dispose();
     });
   });

packages/flutter_test/lib/src/matchers.dart

@@ -442,6 +442,7 @@ Matcher matchesSemantics({
   bool isButton = false,
   bool isLink = false,
   bool isFocused = false,
+  bool isFocusable = false,
   bool isTextField = false,
   bool isReadOnly = false,
   bool hasEnabledState = false,
@@ -494,6 +495,7 @@ Matcher matchesSemantics({
     if (isTextField) SemanticsFlag.isTextField,
     if (isReadOnly) SemanticsFlag.isReadOnly,
     if (isFocused) SemanticsFlag.isFocused,
+    if (isFocusable) SemanticsFlag.isFocusable,
     if (hasEnabledState) SemanticsFlag.hasEnabledState,
     if (isEnabled) SemanticsFlag.isEnabled,
     if (isInMutuallyExclusiveGroup) SemanticsFlag.isInMutuallyExclusiveGroup,

packages/flutter_test/test/matchers_test.dart

@@ -553,6 +553,7 @@ void main() {
          isReadOnly: true,
          hasEnabledState: true,
          isFocused: true,
+         isFocusable: true,
          isEnabled: true,
          isInMutuallyExclusiveGroup: true,
          isHeader: true,