Hide text selection toolbar when dragging handles on mobile (#104274)

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

@@ -29,6 +29,11 @@ export 'package:flutter/services.dart' show TextSelectionDelegate;
 /// called.
 const Duration _kDragSelectionUpdateThrottle = Duration(milliseconds: 50);
 
+/// A duration that determines the delay before showing the text selection
+/// toolbar again after dragging either selection handle on Android. Eyeballed
+/// on a Pixel 5 Android API 31 emulator.
+const Duration _kAndroidPostDragShowDelay = Duration(milliseconds: 300);
+
 /// Signature for when a pointer that's dragging to select text has moved again.
 ///
 /// The first argument [startDetails] contains the details of the event that
@@ -782,6 +787,8 @@ class SelectionOverlay {
   /// Controls the fade-in and fade-out animations for the toolbar and handles.
   static const Duration fadeDuration = Duration(milliseconds: 150);
 
+  Timer? _androidPostDragShowTimer;
+
   /// A pair of handles. If this is non-null, there are always 2, though the
   /// second is hidden when the selection is collapsed.
   List<OverlayEntry>? _handles;
@@ -821,7 +828,7 @@ class SelectionOverlay {
   /// Shows the toolbar by inserting it into the [context]'s overlay.
   /// {@endtemplate}
   void showToolbar() {
-    if (_toolbar != null) {
+    if (_toolbar != null || (_hideToolbarWhenDraggingHandles && _isDraggingHandles)) {
       return;
     }
     _toolbar = OverlayEntry(builder: _buildToolbar);
@@ -888,9 +895,62 @@ class SelectionOverlay {
   /// Disposes this object and release resources.
   /// {@endtemplate}
   void dispose() {
+    _androidPostDragShowTimer?.cancel();
+    _androidPostDragShowTimer = null;
     hide();
   }
 
+  final bool _hideToolbarWhenDraggingHandles =
+    <TargetPlatform>{ TargetPlatform.iOS, TargetPlatform.android }.contains(defaultTargetPlatform);
+
+  bool _isDraggingStartHandle = false;
+  bool _isDraggingEndHandle = false;
+  bool get _isDraggingHandles => _isDraggingStartHandle || _isDraggingEndHandle;
+
+  Future<void> _handleDragging() async {
+    // Hide toolbar while dragging either handle on Android and iOS.
+    if (!_hideToolbarWhenDraggingHandles)
+      return;
+
+    if (_isDraggingHandles) {
+      if (defaultTargetPlatform == TargetPlatform.android) {
+        _androidPostDragShowTimer?.cancel();
+        _androidPostDragShowTimer = null;
+      }
+      hideToolbar();
+    } else {
+      if (defaultTargetPlatform == TargetPlatform.android) {
+        _androidPostDragShowTimer = Timer(_kAndroidPostDragShowDelay, showToolbar);
+      } else {
+        showToolbar();
+      }
+    }
+  }
+
+  void _onStartHandleDragStart(DragStartDetails details) {
+    _isDraggingStartHandle = true;
+    _handleDragging();
+    onStartHandleDragStart?.call(details);
+  }
+
+  void _onStartHandleDragEnd(DragEndDetails details) {
+    _isDraggingStartHandle = false;
+    _handleDragging();
+    onStartHandleDragEnd?.call(details);
+  }
+
+  void _onEndHandleDragStart(DragStartDetails details) {
+    _isDraggingEndHandle = true;
+    _handleDragging();
+    onEndHandleDragStart?.call(details);
+  }
+
+  void _onEndHandleDragEnd(DragEndDetails details) {
+    _isDraggingEndHandle = false;
+    _handleDragging();
+    onEndHandleDragEnd?.call(details);
+  }
+
   Widget _buildStartHandle(BuildContext context) {
     final Widget handle;
     final TextSelectionControls? selectionControls = this.selectionControls;
@@ -901,9 +961,9 @@ class SelectionOverlay {
         type: _startHandleType,
         handleLayerLink: startHandleLayerLink,
         onSelectionHandleTapped: onSelectionHandleTapped,
-        onSelectionHandleDragStart: onStartHandleDragStart,
+        onSelectionHandleDragStart: _onStartHandleDragStart,
         onSelectionHandleDragUpdate: onStartHandleDragUpdate,
-        onSelectionHandleDragEnd: onStartHandleDragEnd,
+        onSelectionHandleDragEnd: _onStartHandleDragEnd,
         selectionControls: selectionControls,
         visibility: startHandlesVisible,
         preferredLineHeight: _lineHeightAtStart,
@@ -926,9 +986,9 @@ class SelectionOverlay {
         type: _endHandleType,
         handleLayerLink: endHandleLayerLink,
         onSelectionHandleTapped: onSelectionHandleTapped,
-        onSelectionHandleDragStart: onEndHandleDragStart,
+        onSelectionHandleDragStart: _onEndHandleDragStart,
         onSelectionHandleDragUpdate: onEndHandleDragUpdate,
-        onSelectionHandleDragEnd: onEndHandleDragEnd,
+        onSelectionHandleDragEnd: _onEndHandleDragEnd,
         selectionControls: selectionControls,
         visibility: endHandlesVisible,
         preferredLineHeight: _lineHeightAtEnd,

packages/flutter/test/material/text_field_test.dart

@@ -3179,6 +3179,11 @@ void main() {
     expect(controller.selection.extentOffset, 50);
 
     if (!isContextMenuProvidedByPlatform) {
+      if (defaultTargetPlatform == TargetPlatform.android) {
+        // There should be a delay before the toolbar is shown again on Android.
+        expect(find.text('Cut'), findsNothing);
+        await tester.pump(const Duration(milliseconds: 300));
+      }
       await tester.tap(find.text('Cut'));
       await tester.pump();
       expect(controller.selection.isCollapsed, true);

packages/flutter/test/widgets/editable_text_test.dart

@@ -1553,6 +1553,69 @@ void main() {
     // toolbar. Until we change that, this test should remain skipped.
   }, skip: kIsWeb, variant: const TargetPlatformVariant(<TargetPlatform>{ TargetPlatform.iOS, TargetPlatform.android })); // [intended]
 
+  testWidgets('dragging handles hides toolbar on mobile', (WidgetTester tester) async {
+    controller.text = 'blah blah blah';
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: EditableText(
+          backgroundCursorColor: Colors.grey,
+          controller: controller,
+          focusNode: focusNode,
+          style: textStyle,
+          cursorColor: cursorColor,
+          selectionControls: materialTextSelectionControls,
+        ),
+      ),
+    );
+
+    final EditableTextState state =
+    tester.state<EditableTextState>(find.byType(EditableText));
+
+    // Show the toolbar
+    state.renderEditable.selectWordsInRange(
+      from: Offset.zero,
+      cause: SelectionChangedCause.tap,
+    );
+    await tester.pump();
+
+    expect(state.showToolbar(), true);
+    await tester.pumpAndSettle();
+    expect(find.text('Paste'), findsOneWidget);
+
+    final List<TextSelectionPoint> endpoints = globalize(
+      state.renderEditable.getEndpointsForSelection(state.textEditingValue.selection),
+      state.renderEditable,
+    );
+    expect(endpoints.length, 2);
+
+    // We use a small offset because the endpoint is on the very corner of the
+    // handle.
+    final Offset endHandlePosition = endpoints[1].point + const Offset(1.0, 1.0);
+
+    // Select 2 more characters by dragging end handle.
+    final TestGesture gesture = await tester.startGesture(endHandlePosition);
+    await gesture.moveTo(textOffsetToPosition(tester, 6));
+    await tester.pumpAndSettle();
+    expect(find.text('Paste'), findsNothing);
+
+    // End drag gesture and expect toolbar to show again.
+    await gesture.up();
+    if (defaultTargetPlatform == TargetPlatform.android) {
+      // There should be a delay before the toolbar is shown again on Android.
+      expect(find.text('Paste'), findsNothing);
+      await tester.pump(const Duration(milliseconds: 300));
+    }
+    await tester.pumpAndSettle();
+    expect(find.text('Paste'), findsOneWidget);
+
+    // On web, we don't show the Flutter toolbar and instead rely on the browser
+    // toolbar. Until we change that, this test should remain skipped.
+  },
+    skip: kIsWeb, // [intended]
+    variant: const TargetPlatformVariant(<TargetPlatform>{ TargetPlatform.iOS, TargetPlatform.android }),
+  );
+
   testWidgets('Paste is shown only when there is something to paste', (WidgetTester tester) async {
     await tester.pumpWidget(
       MaterialApp(

packages/flutter/test/widgets/selectable_text_test.dart

@@ -1132,7 +1132,12 @@ void main() {
     await gesture.moveTo(newHandlePos);
     await tester.pump();
     await gesture.up();
-    await tester.pump();
+    if (defaultTargetPlatform == TargetPlatform.android) {
+      // There should be a delay before the toolbar is shown again on Android.
+      expect(find.text('Cut'), findsNothing);
+      await tester.pump(const Duration(milliseconds: 300));
+    }
+    await tester.pumpAndSettle();
 
     expect(controller.selection.baseOffset, 5);
     expect(controller.selection.extentOffset, 50);

packages/flutter/test/widgets/text_selection_test.dart

@@ -1246,6 +1246,8 @@ void main() {
       await gesture2.up();
       await tester.pump(const Duration(milliseconds: 20));
       expect(endDragEndDetails, isNotNull);
+
+      selectionOverlay.dispose();
     });
   });