[TextSelectionControls] move the tap gesture callback into...

[TextSelectionControls] move the tap gesture callback into _TextSelectionHandlePainter, remove `_TransparentTapGestureRecognizer`. (#83639)

packages/flutter/lib/src/cupertino/desktop_text_selection.dart

@@ -67,7 +67,7 @@ class _CupertinoDesktopTextSelectionControls extends TextSelectionControls {
 
   /// Builds the text selection handles, but desktop has none.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, VoidCallback? onTap) {
     return const SizedBox.shrink();
   }
 

packages/flutter/lib/src/cupertino/text_selection.dart

@@ -247,7 +247,9 @@ class CupertinoTextSelectionControls extends TextSelectionControls {
 
   /// Builder for iOS text selection edges.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, VoidCallback? onTap) {
+    // iOS selection handles do not respond to taps.
+
     // We want a size that's a vertical line the height of the text plus a 18.0
     // padding in every direction that will constitute the selection drag area.
     final Size desiredSize = getHandleSize(textLineHeight);

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

@@ -53,7 +53,7 @@ class _DesktopTextSelectionControls extends TextSelectionControls {
 
   /// Builds the text selection handles, but desktop has none.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, VoidCallback? onTap) {
     return const SizedBox.shrink();
   }
 

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

@@ -54,7 +54,7 @@ class MaterialTextSelectionControls extends TextSelectionControls {
 
   /// Builder for material-style text selection handles.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textHeight) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textHeight, VoidCallback? onTap) {
     final ThemeData theme = Theme.of(context);
     final Color handleColor = TextSelectionTheme.of(context).selectionHandleColor ?? theme.colorScheme.primary;
     final Widget handle = SizedBox(
@@ -64,6 +64,10 @@ class MaterialTextSelectionControls extends TextSelectionControls {
         painter: _TextSelectionHandlePainter(
           color: handleColor,
         ),
+        child: GestureDetector(
+          onTap: onTap,
+          behavior: HitTestBehavior.translucent,
+        ),
       ),
     );
 

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

@@ -110,11 +110,16 @@ class ToolbarItemsParentData extends ContainerBoxParentData<RenderBox> {
 ///
 /// Override text operations such as [handleCut] if needed.
 abstract class TextSelectionControls {
-  /// Builds a selection handle of the given type.
+  /// Builds a selection handle of the given `type`.
   ///
   /// The top left corner of this widget is positioned at the bottom of the
   /// selection position.
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight);
+  ///
+  /// The supplied [onTap] should be invoked when the handle is tapped, if such
+  /// interaction is allowed. As a counterexample, the default selection handle
+  /// on iOS [cupertinoTextSelectionControls] does not call [onTap] at all,
+  /// since its handles are not meant to be tapped.
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, VoidCallback? onTap);
 
   /// Get the anchor point of the handle relative to itself. The anchor point is
   /// the point that is aligned with a specific point in the text. A handle
@@ -401,11 +406,19 @@ class TextSelectionOverlay {
   final DragStartBehavior dragStartBehavior;
 
   /// {@template flutter.widgets.TextSelectionOverlay.onSelectionHandleTapped}
-  /// A callback that's invoked when a selection handle is tapped.
-  ///
-  /// Both regular taps and long presses invoke this callback, but a drag
-  /// gesture won't.
+  /// A callback that's optionally invoked when a selection handle is tapped.
+  ///
+  /// The [TextSelectionControls.buildHandle] implementation the text field
+  /// uses decides where the the handle's tap "hotspot" is, or whether the
+  /// selection handle supports tap gestures at all. For instance,
+  /// [MaterialTextSelectionControls] calls [onSelectionHandleTapped] when the
+  /// selection handle's "knob" is tapped, while
+  /// [CupertinoTextSelectionControls] builds a handle that's not sufficiently
+  /// large for tapping (as it's not meant to be tapped) so it does not call
+  /// [onSelectionHandleTapped] even when tapped.
   /// {@endtemplate}
+  // See https://github.com/flutter/flutter/issues/39376#issuecomment-848406415
+  // for provenance.
   final VoidCallback? onSelectionHandleTapped;
 
   /// Maintains the status of the clipboard for determining if its contents can
@@ -568,7 +581,8 @@ class TextSelectionOverlay {
   }
 
   Widget _buildHandle(BuildContext context, _TextSelectionHandlePosition position) {
-    Widget handle;
+    final Widget handle;
+    final TextSelectionControls? selectionControls = this.selectionControls;
     if ((_selection.isCollapsed && position == _TextSelectionHandlePosition.end) ||
          selectionControls == null)
       handle = Container(); // hide the second handle when collapsed
@@ -690,7 +704,7 @@ class _TextSelectionHandleOverlay extends StatefulWidget {
   final RenderEditable renderObject;
   final ValueChanged<TextSelection> onSelectionHandleChanged;
   final VoidCallback? onSelectionHandleTapped;
-  final TextSelectionControls? selectionControls;
+  final TextSelectionControls selectionControls;
   final DragStartBehavior dragStartBehavior;
 
   @override
@@ -747,7 +761,7 @@ class _TextSelectionHandleOverlayState
   }
 
   void _handleDragStart(DragStartDetails details) {
-    final Size handleSize = widget.selectionControls!.getHandleSize(
+    final Size handleSize = widget.selectionControls.getHandleSize(
       widget.renderObject.preferredLineHeight,
     );
     _dragPosition = details.globalPosition + Offset(0.0, -handleSize.height);
@@ -784,10 +798,6 @@ class _TextSelectionHandleOverlayState
     widget.onSelectionHandleChanged(newSelection);
   }
 
-  void _handleTap() {
-    widget.onSelectionHandleTapped?.call();
-  }
-
   @override
   Widget build(BuildContext context) {
     final LayerLink layerLink;
@@ -814,11 +824,11 @@ class _TextSelectionHandleOverlayState
         break;
     }
 
-    final Offset handleAnchor = widget.selectionControls!.getHandleAnchor(
+    final Offset handleAnchor = widget.selectionControls.getHandleAnchor(
       type,
       widget.renderObject.preferredLineHeight,
     );
-    final Size handleSize = widget.selectionControls!.getHandleSize(
+    final Size handleSize = widget.selectionControls.getHandleSize(
       widget.renderObject.preferredLineHeight,
     );
 
@@ -855,7 +865,6 @@ class _TextSelectionHandleOverlayState
             dragStartBehavior: widget.dragStartBehavior,
             onPanStart: _handleDragStart,
             onPanUpdate: _handleDragUpdate,
-            onTap: _handleTap,
             child: Padding(
               padding: EdgeInsets.only(
                 left: padding.left,
@@ -863,10 +872,11 @@ class _TextSelectionHandleOverlayState
                 right: padding.right,
                 bottom: padding.bottom,
               ),
-              child: widget.selectionControls!.buildHandle(
+              child: widget.selectionControls.buildHandle(
                 context,
                 type,
                 widget.renderObject.preferredLineHeight,
+                widget.onSelectionHandleTapped,
               ),
             ),
           ),
@@ -1520,12 +1530,9 @@ class _TextSelectionGestureDetectorState extends State<TextSelectionGestureDetec
   Widget build(BuildContext context) {
     final Map<Type, GestureRecognizerFactory> gestures = <Type, GestureRecognizerFactory>{};
 
-    // Use _TransparentTapGestureRecognizer so that TextSelectionGestureDetector
-    // can receive the same tap events that a selection handle placed visually
-    // on top of it also receives.
-    gestures[_TransparentTapGestureRecognizer] = GestureRecognizerFactoryWithHandlers<_TransparentTapGestureRecognizer>(
-      () => _TransparentTapGestureRecognizer(debugOwner: this),
-      (_TransparentTapGestureRecognizer instance) {
+    gestures[TapGestureRecognizer] = GestureRecognizerFactoryWithHandlers<TapGestureRecognizer>(
+      () => TapGestureRecognizer(debugOwner: this),
+      (TapGestureRecognizer instance) {
         instance
           ..onSecondaryTap = widget.onSecondaryTap
           ..onSecondaryTapDown = widget.onSecondaryTapDown
@@ -1588,35 +1595,6 @@ class _TextSelectionGestureDetectorState extends State<TextSelectionGestureDetec
   }
 }
 
-// A TapGestureRecognizer which allows other GestureRecognizers to win in the
-// GestureArena. This means both _TransparentTapGestureRecognizer and other
-// GestureRecognizers can handle the same event.
-//
-// This enables proper handling of events on both the selection handle and the
-// underlying input, since there is significant overlap between the two given
-// the handle's padded hit area.  For example, the selection handle needs to
-// handle single taps on itself, but double taps need to be handled by the
-// underlying input.
-class _TransparentTapGestureRecognizer extends TapGestureRecognizer {
-  _TransparentTapGestureRecognizer({
-    Object? debugOwner,
-  }) : super(debugOwner: debugOwner);
-
-  @override
-  void rejectGesture(int pointer) {
-    // Accept new gestures that another recognizer has already won.
-    // Specifically, this needs to accept taps on the text selection handle on
-    // behalf of the text field in order to handle double tap to select. It must
-    // not accept other gestures like longpresses and drags that end outside of
-    // the text field.
-    if (state == GestureRecognizerState.ready) {
-      acceptGesture(pointer);
-    } else {
-      super.rejectGesture(pointer);
-    }
-  }
-}
-
 /// A [ValueNotifier] whose [value] indicates whether the current contents of
 /// the clipboard can be pasted.
 ///

packages/flutter/test/cupertino/text_field_test.dart

@@ -35,7 +35,7 @@ class MockClipboard {
 
 class MockTextSelectionControls extends TextSelectionControls {
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, VoidCallback? onTap) {
     throw UnimplementedError();
   }
 

packages/flutter/test/cupertino/text_selection_test.dart

@@ -156,6 +156,7 @@ void main() {
                       context,
                       TextSelectionHandleType.right,
                       10.0,
+                      null,
                     ),
                   ),
                 ),

packages/flutter/test/material/text_field_test.dart

@@ -488,7 +488,7 @@ void main() {
     await tester.tap(find.byKey(icon));
     await tester.pump();
     expect(controller.text, '');
-    expect(controller.selection, const TextSelection.collapsed(offset: 0, affinity: TextAffinity.upstream));
+    expect(controller.selection, const TextSelection.collapsed(offset: 0, affinity: TextAffinity.downstream));
   });
 
   testWidgets('Cursor radius is 2.0', (WidgetTester tester) async {
@@ -9718,4 +9718,43 @@ void main() {
       expect(state.currentTextEditingValue.composing, TextRange.empty);
     });
   });
+
+  testWidgets('prefix/suffix buttons do not leak touch events', (WidgetTester tester) async {
+    // Regression test for https://github.com/flutter/flutter/issues/39376.
+
+    int textFieldTapCount = 0;
+    int prefixTapCount = 0;
+    int suffixTapCount = 0;
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Scaffold(
+          body: TextField(
+            onTap: () { textFieldTapCount += 1; },
+            decoration: InputDecoration(
+              labelText: 'Label',
+              prefix: RaisedButton(
+                onPressed: () { prefixTapCount += 1; },
+                child: const Text('prefix'),
+              ),
+              suffix: RaisedButton(
+                onPressed: () { suffixTapCount += 1; },
+                child: const Text('suffix'),
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+
+    await tester.tap(find.text('prefix'));
+    expect(textFieldTapCount, 0);
+    expect(prefixTapCount, 1);
+    expect(suffixTapCount, 0);
+
+    await tester.tap(find.text('suffix'));
+    expect(textFieldTapCount, 0);
+    expect(prefixTapCount, 1);
+    expect(suffixTapCount, 1);
+  });
 }

packages/flutter/test/material/text_selection_test.dart

@@ -566,7 +566,7 @@ void main() {
                   padding: const EdgeInsets.symmetric(horizontal: 250),
                   child: FittedBox(
                     child: materialTextSelectionControls.buildHandle(
-                      context, TextSelectionHandleType.right, 10.0,
+                      context, TextSelectionHandleType.right, 10.0, null,
                     ),
                   ),
                 ),

packages/flutter/test/material/text_selection_theme_test.dart

@@ -82,6 +82,7 @@ void main() {
                 context,
                 TextSelectionHandleType.left,
                 10.0,
+                null,
               );
             },
           ),
@@ -129,6 +130,7 @@ void main() {
                 context,
                 TextSelectionHandleType.left,
                 10.0,
+                null,
               );
             },
           ),
@@ -186,6 +188,7 @@ void main() {
                   context,
                   TextSelectionHandleType.left,
                   10.0,
+                  null,
                 );
               },
             ),

packages/flutter/test/widgets/editable_text_test.dart

@@ -706,7 +706,7 @@ void main() {
       tester.renderObjectList<RenderBox>(
         find.descendant(
           of: find.byType(CompositedTransformFollower),
-          matching: find.byType(GestureDetector),
+          matching: find.byType(Padding),
         ),
       ),
     );
@@ -722,7 +722,7 @@ void main() {
       tester.renderObjectList<RenderBox>(
         find.descendant(
           of: find.byType(CompositedTransformFollower),
-          matching: find.byType(GestureDetector),
+          matching: find.byType(Padding),
         ),
       ),
     );
@@ -3907,7 +3907,7 @@ void main() {
         tester.renderObjectList<RenderBox>(
           find.descendant(
             of: find.byType(CompositedTransformFollower),
-            matching: find.byType(GestureDetector),
+            matching: find.byType(Padding),
           ),
         ),
       );
@@ -4027,7 +4027,7 @@ void main() {
       tester.renderObjectList<RenderBox>(
         find.descendant(
           of: find.byType(CompositedTransformFollower),
-          matching: find.byType(GestureDetector),
+          matching: find.byType(Padding),
         ),
       ),
     );
@@ -5058,7 +5058,7 @@ void main() {
         tester.renderObjectList<RenderBox>(
           find.descendant(
             of: find.byType(CompositedTransformFollower),
-            matching: find.byType(GestureDetector),
+            matching: find.byType(Padding),
           ),
         ),
       );
@@ -7569,7 +7569,7 @@ class MockTextSelectionControls extends Fake implements TextSelectionControls {
   }
 
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, VoidCallback? onTap) {
     return Container();
   }