Change text selection (or cursor position) via a11y (#14275)

Roll engine to 7c34dfafc9acece1a9438f206bfbb0a9bedba3bf

bin/internal/engine.version

-4c82c566edf394a5cfc237a266aea5bd37a6c172
+7c34dfafc9acece1a9438f206bfbb0a9bedba3bf

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

@@ -865,6 +865,9 @@ class RenderCustomPaint extends RenderProxyBox {
     if (properties.onMoveCursorBackwardByCharacter != null) {
       config.onMoveCursorBackwardByCharacter = properties.onMoveCursorBackwardByCharacter;
     }
+    if (properties.onSetSelection != null) {
+      config.onSetSelection = properties.onSetSelection;
+    }
 
     newChild.updateWith(
       config: config,

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

@@ -356,6 +356,9 @@ class RenderEditable extends RenderBox {
       ..isFocused = hasFocus
       ..isTextField = true;
 
+    if (hasFocus)
+      config.onSetSelection = _handleSetSelection;
+
     if (_selection?.isValid == true) {
       config.textSelection = _selection;
       if (_textPainter.getOffsetBefore(_selection.extentOffset) != null)
@@ -365,6 +368,10 @@ class RenderEditable extends RenderBox {
     }
   }
 
+  void _handleSetSelection(TextSelection selection) {
+    onSelectionChanged(selection, this, SelectionChangedCause.keyboard);
+  }
+
   void _handleMoveCursorForwardByCharacter(bool extentSelection) {
     final int extentOffset = _textPainter.getOffsetAfter(_selection.extentOffset);
     if (extentOffset == null)

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

@@ -3017,6 +3017,7 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
     VoidCallback onDecrease,
     MoveCursorHandler onMoveCursorForwardByCharacter,
     MoveCursorHandler onMoveCursorBackwardByCharacter,
+    SetSelectionHandler onSetSelection,
   }) : assert(container != null),
        _container = container,
        _explicitChildNodes = explicitChildNodes,
@@ -3040,6 +3041,7 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
        _onDecrease = onDecrease,
        _onMoveCursorForwardByCharacter = onMoveCursorForwardByCharacter,
        _onMoveCursorBackwardByCharacter = onMoveCursorBackwardByCharacter,
+       _onSetSelection = onSetSelection,
        super(child);
 
   /// If 'container' is true, this [RenderObject] will introduce a new
@@ -3399,6 +3401,24 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
       markNeedsSemanticsUpdate();
   }
 
+  /// The handler for [SemanticsAction.setSelection].
+  ///
+  /// This handler is invoked when the user either wants to change the currently
+  /// selected text in a text field or change the position of the cursor.
+  ///
+  /// TalkBack users can trigger this handler by selecting "Move cursor to
+  /// beginning/end" or "Select all" from the local context menu.
+  SetSelectionHandler get onSetSelection => _onSetSelection;
+  SetSelectionHandler _onSetSelection;
+  set onSetSelection(SetSelectionHandler handler) {
+    if (_onSetSelection == handler)
+      return;
+    final bool hadValue = _onSetSelection != null;
+    _onSetSelection = handler;
+    if ((handler != null) != hadValue)
+      markNeedsSemanticsUpdate();
+  }
+
   @override
   void describeSemanticsConfiguration(SemanticsConfiguration config) {
     super.describeSemanticsConfiguration(config);
@@ -3448,6 +3468,8 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
       config.onMoveCursorForwardByCharacter = _performMoveCursorForwardByCharacter;
     if (onMoveCursorBackwardByCharacter != null)
       config.onMoveCursorBackwardByCharacter = _performMoveCursorBackwardByCharacter;
+    if (onSetSelection != null)
+      config.onSetSelection = _performSetSelection;
   }
 
   void _performTap() {
@@ -3499,6 +3521,11 @@ class RenderSemanticsAnnotations extends RenderProxyBox {
     if (onMoveCursorBackwardByCharacter != null)
       onMoveCursorBackwardByCharacter(extendSelection);
   }
+
+  void _performSetSelection(TextSelection selection) {
+    if (onSetSelection != null)
+      onSetSelection(selection);
+  }
 }
 
 /// Causes the semantics of all earlier render objects below the same semantic

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

@@ -31,6 +31,10 @@ typedef bool SemanticsNodeVisitor(SemanticsNode node);
 /// current selection or (if nothing is currently selected) start a selection.
 typedef void MoveCursorHandler(bool extendSelection);
 
+/// Signature for the [SemanticsAction.setSelection] handlers to change the
+/// text selection (or re-position the cursor) to `selection`.
+typedef void SetSelectionHandler(TextSelection selection);
+
 typedef void _SemanticsActionHandler(dynamic args);
 
 /// A tag for a [SemanticsNode].
@@ -275,6 +279,7 @@ class SemanticsProperties extends DiagnosticableTree {
     this.onDecrease,
     this.onMoveCursorForwardByCharacter,
     this.onMoveCursorBackwardByCharacter,
+    this.onSetSelection,
   });
 
   /// If non-null, indicates that this subtree represents something that can be
@@ -485,6 +490,15 @@ class SemanticsProperties extends DiagnosticableTree {
   /// input focus is in a text field.
   final MoveCursorHandler onMoveCursorBackwardByCharacter;
 
+  /// The handler for [SemanticsAction.setSelection].
+  ///
+  /// This handler is invoked when the user either wants to change the currently
+  /// selected text in a text field or change the position of the cursor.
+  ///
+  /// TalkBack users can trigger this handler by selecting "Move cursor to
+  /// beginning/end" or "Select all" from the local context menu.
+  final SetSelectionHandler onSetSelection;
+
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder description) {
     super.debugFillProperties(description);
@@ -1658,6 +1672,28 @@ class SemanticsConfiguration {
     _onMoveCursorBackwardByCharacter = value;
   }
 
+  /// The handler for [SemanticsAction.setSelection].
+  ///
+  /// This handler is invoked when the user either wants to change the currently
+  /// selected text in a text field or change the position of the cursor.
+  ///
+  /// TalkBack users can trigger this handler by selecting "Move cursor to
+  /// beginning/end" or "Select all" from the local context menu.
+  SetSelectionHandler get onSetSelection => _onSetSelection;
+  SetSelectionHandler _onSetSelection;
+  set onSetSelection(SetSelectionHandler value) {
+    assert(value != null);
+    _addAction(SemanticsAction.setSelection, (dynamic args) {
+      final Map<String, int> selection = args;
+      assert(selection != null && selection['base'] != null && selection['extent'] != null);
+      value(new TextSelection(
+        baseOffset: selection['base'],
+        extentOffset: selection['extent'],
+      ));
+    });
+    _onSetSelection = value;
+  }
+
   /// Returns the action handler registered for [action] or null if none was
   /// registered.
   ///

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

@@ -4854,6 +4854,7 @@ class Semantics extends SingleChildRenderObjectWidget {
     VoidCallback onDecrease,
     MoveCursorHandler onMoveCursorForwardByCharacter,
     MoveCursorHandler onMoveCursorBackwardByCharacter,
+    SetSelectionHandler onSetSelection,
   }) : this.fromProperties(
     key: key,
     child: child,
@@ -4880,6 +4881,7 @@ class Semantics extends SingleChildRenderObjectWidget {
       onDecrease: onDecrease,
       onMoveCursorForwardByCharacter: onMoveCursorForwardByCharacter,
       onMoveCursorBackwardByCharacter: onMoveCursorBackwardByCharacter,
+      onSetSelection: onSetSelection,
     ),
   );
 
@@ -4948,6 +4950,7 @@ class Semantics extends SingleChildRenderObjectWidget {
       onDecrease: properties.onDecrease,
       onMoveCursorForwardByCharacter: properties.onMoveCursorForwardByCharacter,
       onMoveCursorBackwardByCharacter: properties.onMoveCursorBackwardByCharacter,
+      onSetSelection: properties.onSetSelection,
     );
   }
 
@@ -4986,7 +4989,8 @@ class Semantics extends SingleChildRenderObjectWidget {
       ..onIncrease = properties.onIncrease
       ..onDecrease = properties.onDecrease
       ..onMoveCursorForwardByCharacter = properties.onMoveCursorForwardByCharacter
-      ..onMoveCursorBackwardByCharacter = properties.onMoveCursorForwardByCharacter;
+      ..onMoveCursorBackwardByCharacter = properties.onMoveCursorForwardByCharacter
+      ..onSetSelection = properties.onSetSelection;
   }
 
   @override

packages/flutter/test/material/text_field_test.dart

@@ -1761,7 +1761,7 @@ void main() {
         child: new TextField(
           key: key,
           controller: controller,
-        )
+        ),
       ),
     );
 
@@ -1812,6 +1812,7 @@ void main() {
           actions: <SemanticsAction>[
             SemanticsAction.tap,
             SemanticsAction.moveCursorBackwardByCharacter,
+            SemanticsAction.setSelection,
           ],
           flags: <SemanticsFlag>[
             SemanticsFlag.isTextField,
@@ -1835,6 +1836,7 @@ void main() {
             SemanticsAction.tap,
             SemanticsAction.moveCursorBackwardByCharacter,
             SemanticsAction.moveCursorForwardByCharacter,
+            SemanticsAction.setSelection,
           ],
           flags: <SemanticsFlag>[
             SemanticsFlag.isTextField,
@@ -1858,6 +1860,7 @@ void main() {
           actions: <SemanticsAction>[
             SemanticsAction.tap,
             SemanticsAction.moveCursorForwardByCharacter,
+            SemanticsAction.setSelection,
           ],
           flags: <SemanticsFlag>[
             SemanticsFlag.isTextField,
@@ -1878,10 +1881,10 @@ void main() {
 
     await tester.pumpWidget(
       overlay(
-          child: new TextField(
-            key: key,
-            controller: controller,
-          )
+        child: new TextField(
+          key: key,
+          controller: controller,
+        ),
       ),
     );
 
@@ -1915,6 +1918,7 @@ void main() {
           actions: <SemanticsAction>[
             SemanticsAction.tap,
             SemanticsAction.moveCursorBackwardByCharacter,
+            SemanticsAction.setSelection,
           ],
           flags: <SemanticsFlag>[
             SemanticsFlag.isTextField,
@@ -1938,6 +1942,7 @@ void main() {
             SemanticsAction.tap,
             SemanticsAction.moveCursorBackwardByCharacter,
             SemanticsAction.moveCursorForwardByCharacter,
+            SemanticsAction.setSelection,
           ],
           flags: <SemanticsFlag>[
             SemanticsFlag.isTextField,
@@ -1950,4 +1955,94 @@ void main() {
     semantics.dispose();
   });
 
+  testWidgets('TextField change selection with semantics', (WidgetTester tester) async {
+    final SemanticsTester semantics = new SemanticsTester(tester);
+    final SemanticsOwner semanticsOwner = tester.binding.pipelineOwner.semanticsOwner;
+    final TextEditingController controller = new TextEditingController()
+      ..text = 'Hello';
+    final Key key = new UniqueKey();
+
+    await tester.pumpWidget(
+      overlay(
+        child: new TextField(
+          key: key,
+          controller: controller,
+        ),
+      ),
+    );
+
+    // Focus the text field
+    await tester.tap(find.byKey(key));
+    await tester.pump();
+
+    const int inputFieldId = 2;
+
+    expect(controller.selection, const TextSelection.collapsed(offset: 5, affinity: TextAffinity.upstream));
+    expect(semantics, hasSemantics(new TestSemantics.root(
+      children: <TestSemantics>[
+        new TestSemantics.rootChild(
+          id: inputFieldId,
+          value: 'Hello',
+          textSelection: const TextSelection.collapsed(offset: 5),
+          textDirection: TextDirection.ltr,
+          actions: <SemanticsAction>[
+            SemanticsAction.tap,
+            SemanticsAction.moveCursorBackwardByCharacter,
+            SemanticsAction.setSelection,
+          ],
+          flags: <SemanticsFlag>[
+            SemanticsFlag.isTextField,
+            SemanticsFlag.isFocused,
+          ],
+        ),
+      ],
+    ), ignoreTransform: true, ignoreRect: true));
+
+    // move cursor back once
+    semanticsOwner.performAction(inputFieldId, SemanticsAction.setSelection, <String, int>{
+      'base': 4,
+      'extent': 4,
+    });
+    await tester.pump();
+    expect(controller.selection, const TextSelection.collapsed(offset: 4));
+
+    // move cursor to front
+    semanticsOwner.performAction(inputFieldId, SemanticsAction.setSelection, <String, int>{
+      'base': 0,
+      'extent': 0,
+    });
+    await tester.pump();
+    expect(controller.selection, const TextSelection.collapsed(offset: 0));
+
+    // select all
+    semanticsOwner.performAction(inputFieldId, SemanticsAction.setSelection, <String, int>{
+      'base': 0,
+      'extent': 5,
+    });
+    await tester.pump();
+    expect(controller.selection, const TextSelection(baseOffset: 0, extentOffset: 5));
+    expect(semantics, hasSemantics(new TestSemantics.root(
+      children: <TestSemantics>[
+        new TestSemantics.rootChild(
+          id: inputFieldId,
+          value: 'Hello',
+          textSelection: const TextSelection(baseOffset: 0, extentOffset: 5),
+          textDirection: TextDirection.ltr,
+          actions: <SemanticsAction>[
+            SemanticsAction.tap,
+            SemanticsAction.moveCursorBackwardByCharacter,
+            SemanticsAction.setSelection,
+          ],
+          flags: <SemanticsFlag>[
+            SemanticsFlag.isTextField,
+            SemanticsFlag.isFocused,
+          ],
+        ),
+      ],
+    ), ignoreTransform: true, ignoreRect: true));
+
+    semantics.dispose();
+  });
+
+
 }

packages/flutter/test/widgets/editable_text_test.dart

@@ -383,6 +383,7 @@ void main() {
       value: 'test',
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorBackwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 
@@ -395,6 +396,7 @@ void main() {
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorBackwardByCharacter,
         SemanticsAction.moveCursorForwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 
@@ -406,6 +408,7 @@ void main() {
       value: 'test',
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorForwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 
@@ -452,6 +455,7 @@ void main() {
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorBackwardByCharacter,
         SemanticsAction.moveCursorForwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 
@@ -470,6 +474,7 @@ void main() {
       value: 'test',
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorForwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 
@@ -523,6 +528,7 @@ void main() {
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorBackwardByCharacter,
         SemanticsAction.moveCursorForwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 
@@ -541,6 +547,7 @@ void main() {
       value: 'test',
       actions: <SemanticsAction>[
         SemanticsAction.moveCursorForwardByCharacter,
+        SemanticsAction.setSelection,
       ],
     ));
 

packages/flutter/test/widgets/semantics_test.dart

@@ -11,6 +11,10 @@ import 'package:flutter_test/flutter_test.dart';
 import 'semantics_tester.dart';
 
 void main() {
+  setUp(() {
+    debugResetSemanticsIdCounter();
+  });
+
   testWidgets('Semantics shutdown and restart', (WidgetTester tester) async {
     SemanticsTester semantics = new SemanticsTester(tester);
 
@@ -390,13 +394,14 @@ void main() {
         onDecrease: () => performedActions.add(SemanticsAction.decrease),
         onMoveCursorForwardByCharacter: (bool _) => performedActions.add(SemanticsAction.moveCursorForwardByCharacter),
         onMoveCursorBackwardByCharacter: (bool _) => performedActions.add(SemanticsAction.moveCursorBackwardByCharacter),
+        onSetSelection: (TextSelection _) => performedActions.add(SemanticsAction.setSelection),
       )
     );
 
     final Set<SemanticsAction> allActions = SemanticsAction.values.values.toSet()
       ..remove(SemanticsAction.showOnScreen); // showOnScreen is non user-exposed.
 
-    final int expectedId = 32;
+    const int expectedId = 2;
     final TestSemantics expectedSemantics = new TestSemantics.root(
       children: <TestSemantics>[
         new TestSemantics.rootChild(
@@ -417,6 +422,12 @@ void main() {
         case SemanticsAction.moveCursorForwardByCharacter:
           semanticsOwner.performAction(expectedId, action, true);
           break;
+        case SemanticsAction.setSelection:
+          semanticsOwner.performAction(expectedId, action, <String, int>{
+            'base': 4,
+            'extent': 5,
+          });
+          break;
         default:
           semanticsOwner.performAction(expectedId, action);
       }
@@ -446,7 +457,7 @@ void main() {
       ),
     );
 
-    final int expectedId = 35;
+    const int expectedId = 2;
     final TestSemantics expectedSemantics = new TestSemantics.root(
       children: <TestSemantics>[
         new TestSemantics.rootChild(