Unify Text selection API (#98073)

* Unify Text selection API

* fix test

* further simplify

* fix more tests

* styling change

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

@@ -67,13 +67,13 @@ class _CupertinoDesktopTextSelectionControls extends TextSelectionControls {
 
   /// Builds the text selection handles, but desktop has none.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap]) {
     return const SizedBox.shrink();
   }
 
   /// Gets the position for the text selection handles, but desktop has none.
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     return Offset.zero;
   }
 }

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

@@ -247,14 +247,8 @@ class CupertinoTextSelectionControls extends TextSelectionControls {
 
   /// Builder for iOS text selection edges.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  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.
-    startGlyphHeight = startGlyphHeight ?? textLineHeight;
-    endGlyphHeight = endGlyphHeight ?? textLineHeight;
-
     final Size desiredSize;
     final Widget handle;
 
@@ -267,14 +261,14 @@ class CupertinoTextSelectionControls extends TextSelectionControls {
     // on top of the text selection endpoints.
     switch (type) {
       case TextSelectionHandleType.left:
-        desiredSize = getHandleSize(startGlyphHeight);
+        desiredSize = getHandleSize(textLineHeight);
         handle = SizedBox.fromSize(
           size: desiredSize,
           child: customPaint,
         );
         return handle;
       case TextSelectionHandleType.right:
-        desiredSize = getHandleSize(endGlyphHeight);
+        desiredSize = getHandleSize(textLineHeight);
         handle = SizedBox.fromSize(
           size: desiredSize,
           child: customPaint,
@@ -296,17 +290,14 @@ class CupertinoTextSelectionControls extends TextSelectionControls {
   ///
   /// See [TextSelectionControls.getHandleAnchor].
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
-    startGlyphHeight = startGlyphHeight ?? textLineHeight;
-    endGlyphHeight = endGlyphHeight ?? textLineHeight;
-
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     final Size handleSize;
 
     switch (type) {
       // The circle is at the top for the left handle, and the anchor point is
       // all the way at the bottom of the line.
       case TextSelectionHandleType.left:
-        handleSize = getHandleSize(startGlyphHeight);
+        handleSize = getHandleSize(textLineHeight);
         return Offset(
           handleSize.width / 2,
           handleSize.height,
@@ -314,7 +305,7 @@ class CupertinoTextSelectionControls extends TextSelectionControls {
       // The right handle is vertically flipped, and the anchor point is near
       // the top of the circle to give slight overlap.
       case TextSelectionHandleType.right:
-        handleSize = getHandleSize(endGlyphHeight);
+        handleSize = getHandleSize(textLineHeight);
         return Offset(
           handleSize.width / 2,
           handleSize.height - 2 * _kSelectionHandleRadius + _kSelectionHandleOverlap,

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

@@ -53,13 +53,13 @@ class _DesktopTextSelectionControls extends TextSelectionControls {
 
   /// Builds the text selection handles, but desktop has none.
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap]) {
     return const SizedBox.shrink();
   }
 
   /// Gets the position for the text selection handles, but desktop has none.
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     return Offset.zero;
   }
 

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, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  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(
@@ -94,7 +94,7 @@ class MaterialTextSelectionControls extends TextSelectionControls {
   ///
   /// See [TextSelectionControls.getHandleAnchor].
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     switch (type) {
       case TextSelectionHandleType.left:
         return const Offset(_kHandleSize, 0);

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

@@ -22,7 +22,6 @@ import 'gesture_detector.dart';
 import 'overlay.dart';
 import 'ticker_provider.dart';
 import 'transitions.dart';
-import 'visibility.dart';
 
 export 'package:flutter/services.dart' show TextSelectionDelegate;
 
@@ -116,12 +115,12 @@ abstract class TextSelectionControls {
   /// 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, double? startGlyphHeight, double? endGlyphHeight]);
+  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
   /// often visually "points to" that location.
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]);
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight);
 
   /// Builds a toolbar near a text selection.
   ///
@@ -274,6 +273,9 @@ class TextSelectionOverlay {
       'Usually the Navigator created by WidgetsApp provides the overlay. Perhaps your '
       'app content was created above the Navigator with the WidgetsApp builder parameter.',
     );
+    renderObject.selectionStartInViewport.addListener(_updateHandleVisibilities);
+    renderObject.selectionEndInViewport.addListener(_updateHandleVisibilities);
+    _updateHandleVisibilities();
     _toolbarController = AnimationController(duration: fadeDuration, vsync: overlay!);
   }
 
@@ -372,6 +374,13 @@ class TextSelectionOverlay {
 
   TextSelection get _selection => _value.selection;
 
+  final ValueNotifier<bool> _effectiveStartHandleVisibility = ValueNotifier<bool>(false);
+  final ValueNotifier<bool> _effectiveEndHandleVisibility = ValueNotifier<bool>(false);
+  void _updateHandleVisibilities() {
+    _effectiveStartHandleVisibility.value = _handlesVisible && renderObject.selectionStartInViewport.value;
+    _effectiveEndHandleVisibility.value = _handlesVisible && renderObject.selectionEndInViewport.value;
+  }
+
   /// Whether selection handles are visible.
   ///
   /// Set to false if you want to hide the handles. Use this property to show or
@@ -393,13 +402,7 @@ class TextSelectionOverlay {
     if (_handlesVisible == visible)
       return;
     _handlesVisible = visible;
-    // If we are in build state, it will be too late to update visibility.
-    // We will need to schedule the build in next frame.
-    if (SchedulerBinding.instance.schedulerPhase == SchedulerPhase.persistentCallbacks) {
-      SchedulerBinding.instance.addPostFrameCallback(_markNeedsBuild);
-    } else {
-      _markNeedsBuild();
-    }
+    _updateHandleVisibilities();
   }
 
   /// Builds the handles by inserting them into the [context]'s overlay.
@@ -501,6 +504,8 @@ class TextSelectionOverlay {
   void dispose() {
     hide();
     _toolbarController.dispose();
+    renderObject.selectionStartInViewport.removeListener(_updateHandleVisibilities);
+    renderObject.selectionEndInViewport.removeListener(_updateHandleVisibilities);
   }
 
   Widget _buildStartHandle(BuildContext context) {
@@ -509,9 +514,7 @@ class TextSelectionOverlay {
     if (selectionControls == null)
       handle = Container();
     else {
-      handle = Visibility(
-        visible: handlesVisible,
-        child: _SelectionHandleOverlay(
+      handle = _SelectionHandleOverlay(
         type: _chooseType(
           renderObject.textDirection,
           TextSelectionHandleType.left,
@@ -522,11 +525,9 @@ class TextSelectionOverlay {
         onSelectionHandleDragStart: _handleSelectionStartHandleDragStart,
         onSelectionHandleDragUpdate: _handleSelectionStartHandleDragUpdate,
         selectionControls: selectionControls,
-          visibility: renderObject.selectionStartInViewport,
-          preferredLineHeight: renderObject.preferredLineHeight,
-          glyphHeight: _getStartGlyphHeight(),
+        visibility: _effectiveStartHandleVisibility,
+        preferredLineHeight: _getStartGlyphHeight(),
         dragStartBehavior: dragStartBehavior,
-        )
       );
     }
     return ExcludeSemantics(
@@ -540,9 +541,7 @@ class TextSelectionOverlay {
     if (_selection.isCollapsed || selectionControls == null)
       handle = Container(); // hide the second handle when collapsed
     else {
-      handle = Visibility(
-        visible: handlesVisible,
-        child: _SelectionHandleOverlay(
+      handle = _SelectionHandleOverlay(
         type: _chooseType(
           renderObject.textDirection,
           TextSelectionHandleType.right,
@@ -553,11 +552,9 @@ class TextSelectionOverlay {
         onSelectionHandleDragStart: _handleSelectionEndHandleDragStart,
         onSelectionHandleDragUpdate: _handleSelectionEndHandleDragUpdate,
         selectionControls: selectionControls,
-          visibility: renderObject.selectionEndInViewport,
-          preferredLineHeight: renderObject.preferredLineHeight,
-          glyphHeight: _getEndGlyphHeight(),
+        visibility: _effectiveEndHandleVisibility,
+        preferredLineHeight: _getEndGlyphHeight(),
         dragStartBehavior: dragStartBehavior,
-        )
       );
     }
     return ExcludeSemantics(
@@ -565,7 +562,7 @@ class TextSelectionOverlay {
     );
   }
 
-  double? _getStartGlyphHeight() {
+  double _getStartGlyphHeight() {
     final InlineSpan span = renderObject.text!;
     final String prevText = span.toPlainText();
     final String currText = selectionDelegate.textEditingValue.text;
@@ -583,10 +580,10 @@ class TextSelectionOverlay {
       firstSelectedGraphemeExtent = selectedGraphemes.characters.first.length;
       startHandleRect = renderObject.getRectForComposingRange(TextRange(start: _selection.start, end: _selection.start + firstSelectedGraphemeExtent));
     }
-    return startHandleRect?.height;
+    return startHandleRect?.height ?? renderObject.preferredLineHeight;
   }
 
-  double? _getEndGlyphHeight() {
+  double _getEndGlyphHeight() {
     final InlineSpan span = renderObject.text!;
     final String prevText = span.toPlainText();
     final String currText = selectionDelegate.textEditingValue.text;
@@ -598,7 +595,7 @@ class TextSelectionOverlay {
       lastSelectedGraphemeExtent = selectedGraphemes.characters.last.length;
       endHandleRect = renderObject.getRectForComposingRange(TextRange(start: _selection.end - lastSelectedGraphemeExtent, end: _selection.end));
     }
-    return endHandleRect?.height;
+    return endHandleRect?.height ?? renderObject.preferredLineHeight;
   }
 
   late Offset _dragEndPosition;
@@ -754,7 +751,6 @@ class _SelectionHandleOverlay extends StatefulWidget {
     required this.selectionControls,
     required this.visibility,
     required this.preferredLineHeight,
-    this.glyphHeight,
     this.dragStartBehavior = DragStartBehavior.start,
   }) : super(key: key);
 
@@ -765,7 +761,6 @@ class _SelectionHandleOverlay extends StatefulWidget {
   final TextSelectionControls selectionControls;
   final ValueListenable<bool> visibility;
   final double preferredLineHeight;
-  final double? glyphHeight;
   final TextSelectionHandleType type;
   final DragStartBehavior dragStartBehavior;
 
@@ -817,8 +812,6 @@ class _SelectionHandleOverlayState extends State<_SelectionHandleOverlay> with S
     final Offset handleAnchor = widget.selectionControls.getHandleAnchor(
       widget.type,
       widget.preferredLineHeight,
-      widget.glyphHeight,
-      widget.glyphHeight,
     );
     final Size handleSize = widget.selectionControls.getHandleSize(
       widget.preferredLineHeight,
@@ -869,8 +862,6 @@ class _SelectionHandleOverlayState extends State<_SelectionHandleOverlay> with S
                 widget.type,
                 widget.preferredLineHeight,
                 widget.onSelectionHandleTapped,
-                widget.glyphHeight,
-                widget.glyphHeight,
               ),
             ),
           ),

packages/flutter/test/cupertino/text_field_test.dart

@@ -31,7 +31,7 @@ const bool isContextMenuProvidedByPlatform = isBrowser;
 
 class MockTextSelectionControls extends TextSelectionControls {
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap]) {
     throw UnimplementedError();
   }
 
@@ -50,7 +50,7 @@ class MockTextSelectionControls extends TextSelectionControls {
   }
 
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     throw UnimplementedError();
   }
 

packages/flutter/test/material/text_field_test.dart

@@ -1370,14 +1370,15 @@ void main() {
     // Handle not shown.
     expect(controller.selection.isCollapsed, true);
     final Finder fadeFinder = find.byType(FadeTransition);
-    expect(fadeFinder, findsNothing);
+    FadeTransition handle = tester.widget(fadeFinder.at(0));
+    expect(handle.opacity.value, equals(0.0));
 
     // Tap on the text field to show the handle.
     await tester.tap(find.byType(TextField));
     await tester.pumpAndSettle();
     expect(controller.selection.isCollapsed, true);
     expect(fadeFinder, findsNWidgets(1));
-    final FadeTransition handle = tester.widget(fadeFinder.at(0));
+    handle = tester.widget(fadeFinder.at(0));
     expect(handle.opacity.value, equals(1.0));
 
     // Enter more text.
@@ -1388,7 +1389,8 @@ void main() {
 
     // Handle not shown.
     expect(controller.selection.isCollapsed, true);
-    expect(fadeFinder, findsNothing);
+    handle = tester.widget(fadeFinder.at(0));
+    expect(handle.opacity.value, equals(0.0));
   });
 
   testWidgets('selection handles are excluded from the semantics', (WidgetTester tester) async {

packages/flutter/test/widgets/editable_text_test.dart

@@ -10463,7 +10463,7 @@ class MockTextSelectionControls extends Fake implements TextSelectionControls {
   }
 
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap]) {
     return Container();
   }
 
@@ -10473,7 +10473,7 @@ class MockTextSelectionControls extends Fake implements TextSelectionControls {
   }
 
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     return Offset.zero;
   }
 

packages/flutter/test/widgets/text_selection_test.dart

@@ -707,7 +707,7 @@ void main() {
     await tester.pumpAndSettle();
 
     final Finder gestureDetector = find.descendant(
-      of: find.byType(Visibility),
+      of: find.byType(CompositedTransformFollower),
       matching: find.descendant(
         of: find.byType(FadeTransition),
         matching: find.byType(GestureDetector),
@@ -910,7 +910,7 @@ class FakeRenderEditable extends RenderEditable {
 
 class CustomTextSelectionControls extends TextSelectionControls {
   @override
-  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap, double? startGlyphHeight, double? endGlyphHeight]) {
+  Widget buildHandle(BuildContext context, TextSelectionHandleType type, double textLineHeight, [VoidCallback? onTap]) {
     throw UnimplementedError();
   }
 
@@ -929,7 +929,7 @@ class CustomTextSelectionControls extends TextSelectionControls {
   }
 
   @override
-  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight, [double? startGlyphHeight, double? endGlyphHeight]) {
+  Offset getHandleAnchor(TextSelectionHandleType type, double textLineHeight) {
     throw UnimplementedError();
   }