Fix crash when widgetspan does not produce a semantics node in render… (#69919)
* Fix crash when widgetspan does not produce a semantics node in render paragraph
* fix comments
* fixed corner case, added test, refactored semantics widget
* addressing comment
diff --git a/packages/flutter/lib/src/rendering/paragraph.dart b/packages/flutter/lib/src/rendering/paragraph.dart
index 294efbb..41ca3ba 100644
--- a/packages/flutter/lib/src/rendering/paragraph.dart
+++ b/packages/flutter/lib/src/rendering/paragraph.dart
@@ -54,6 +54,32 @@
}
}
+/// Used by the [RenderParagraph] to map its rendering children to their
+/// corresponding semantics nodes.
+///
+/// The [RichText] uses this to tag the relation between its placeholder spans
+/// and their semantics nodes.
+@immutable
+class PlaceholderSpanIndexSemanticsTag extends SemanticsTag {
+ /// Creates a semantics tag with the input `index`.
+ ///
+ /// Different [PlaceholderSpanIndexSemanticsTag]s with the same `index` are
+ /// consider the same.
+ const PlaceholderSpanIndexSemanticsTag(this.index) : super('PlaceholderSpanIndexSemanticsTag($index)');
+
+ /// The index of this tag.
+ final int index;
+
+ @override
+ bool operator ==(Object other) {
+ return other is PlaceholderSpanIndexSemanticsTag
+ && other.index == index;
+ }
+
+ @override
+ int get hashCode => hashValues(PlaceholderSpanIndexSemanticsTag, index);
+}
+
/// A render object that displays a paragraph of text.
class RenderParagraph extends RenderBox
with ContainerRenderObjectMixin<RenderBox, TextParentData>,
@@ -878,6 +904,7 @@
double ordinal = 0.0;
int start = 0;
int placeholderIndex = 0;
+ int childIndex = 0;
RenderBox? child = firstChild;
final Queue<SemanticsNode> newChildCache = Queue<SemanticsNode>();
for (final InlineSpanSemanticsInformation info in _combineSemanticsInfo()) {
@@ -915,8 +942,11 @@
);
if (info.isPlaceholder) {
- if (children.isNotEmpty) {
- final SemanticsNode childNode = children.elementAt(placeholderIndex++);
+ // A placeholder span may have 0 to multple semantics nodes, we need
+ // to annotate all of the semantics nodes belong to this span.
+ while (children.length > childIndex &&
+ children.elementAt(childIndex).isTagged(PlaceholderSpanIndexSemanticsTag(placeholderIndex))) {
+ final SemanticsNode childNode = children.elementAt(childIndex);
final TextParentData parentData = child!.parentData! as TextParentData;
childNode.rect = Rect.fromLTWH(
childNode.rect.left,
@@ -925,8 +955,10 @@
childNode.rect.height * parentData.scale!,
);
newChildren.add(childNode);
- child = childAfter(child);
+ childIndex += 1;
}
+ child = childAfter(child!);
+ placeholderIndex += 1;
} else {
final SemanticsConfiguration configuration = SemanticsConfiguration()
..sortKey = OrdinalSortKey(ordinal++)
@@ -962,6 +994,10 @@
newChildren.add(newChild);
}
}
+ // Makes sure we annotated all of the semantics children.
+ assert(childIndex == children.length);
+ assert(child == null);
+
_cachedChildNodes = newChildCache;
node.updateWith(config: config, childrenInInversePaintOrder: newChildren);
}
diff --git a/packages/flutter/lib/src/rendering/proxy_box.dart b/packages/flutter/lib/src/rendering/proxy_box.dart
index 40879c3..844b1bb 100644
--- a/packages/flutter/lib/src/rendering/proxy_box.dart
+++ b/packages/flutter/lib/src/rendering/proxy_box.dart
@@ -3600,6 +3600,7 @@
SemanticsHintOverrides? hintOverrides,
TextDirection? textDirection,
SemanticsSortKey? sortKey,
+ SemanticsTag? tagForChildren,
VoidCallback? onTap,
VoidCallback? onDismiss,
VoidCallback? onLongPress,
@@ -3655,6 +3656,7 @@
_hintOverrides = hintOverrides,
_textDirection = textDirection,
_sortKey = sortKey,
+ _tagForChildren = tagForChildren,
_onTap = onTap,
_onLongPress = onLongPress,
_onScrollLeft = onScrollLeft,
@@ -4072,6 +4074,16 @@
markNeedsSemanticsUpdate();
}
+ /// Adds a semenatics tag to the semantics subtree.
+ SemanticsTag? get tagForChildren => _tagForChildren;
+ SemanticsTag? _tagForChildren;
+ set tagForChildren(SemanticsTag? value) {
+ if (_tagForChildren == value)
+ return;
+ markNeedsSemanticsUpdate();
+ _tagForChildren = value;
+ }
+
/// The handler for [SemanticsAction.tap].
///
/// This is the semantic equivalent of a user briefly tapping the screen with
@@ -4549,6 +4561,8 @@
config.textDirection = textDirection;
if (sortKey != null)
config.sortKey = sortKey;
+ if (tagForChildren != null)
+ config.addTagForChildren(tagForChildren!);
// Registering _perform* as action handlers instead of the user provided
// ones to ensure that changing a user provided handler from a non-null to
// another non-null value doesn't require a semantics update.
diff --git a/packages/flutter/lib/src/semantics/semantics.dart b/packages/flutter/lib/src/semantics/semantics.dart
index 882bae6..4665ed0 100644
--- a/packages/flutter/lib/src/semantics/semantics.dart
+++ b/packages/flutter/lib/src/semantics/semantics.dart
@@ -610,6 +610,7 @@
this.hintOverrides,
this.textDirection,
this.sortKey,
+ this.tagForChildren,
this.onTap,
this.onLongPress,
this.onScrollLeft,
@@ -913,6 +914,22 @@
/// on iOS and TalkBack on Android).
final SemanticsSortKey? sortKey;
+ /// A tag to be applied to the child [SemanticsNode]s of this widget.
+ ///
+ /// The tag is added to all child [SemanticsNode]s that pass through the
+ /// [RenderObject] corresponding to this widget while looking to be attached
+ /// to a parent SemanticsNode.
+ ///
+ /// Tags are used to communicate to a parent SemanticsNode that a child
+ /// SemanticsNode was passed through a particular RenderObject. The parent can
+ /// use this information to determine the shape of the semantics tree.
+ ///
+ /// See also:
+ ///
+ /// * [SemanticsConfiguration.addTagForChildren], to which the tags provided
+ /// here will be passed.
+ final SemanticsTag? tagForChildren;
+
/// The handler for [SemanticsAction.tap].
///
/// This is the semantic equivalent of a user briefly tapping the screen with
diff --git a/packages/flutter/lib/src/widgets/basic.dart b/packages/flutter/lib/src/widgets/basic.dart
index a363f36..f41e05d 100644
--- a/packages/flutter/lib/src/widgets/basic.dart
+++ b/packages/flutter/lib/src/widgets/basic.dart
@@ -5456,10 +5456,14 @@
// Traverses the InlineSpan tree and depth-first collects the list of
// child widgets that are created in WidgetSpans.
static List<Widget> _extractChildren(InlineSpan span) {
+ int index = 0;
final List<Widget> result = <Widget>[];
span.visitChildren((InlineSpan span) {
if (span is WidgetSpan) {
- result.add(span.child);
+ result.add(Semantics(
+ tagForChildren: PlaceholderSpanIndexSemanticsTag(index++),
+ child: span.child,
+ ));
}
return true;
});
@@ -6890,6 +6894,7 @@
String? onLongPressHint,
TextDirection? textDirection,
SemanticsSortKey? sortKey,
+ SemanticsTag? tagForChildren,
VoidCallback? onTap,
VoidCallback? onLongPress,
VoidCallback? onScrollLeft,
@@ -6944,6 +6949,7 @@
hint: hint,
textDirection: textDirection,
sortKey: sortKey,
+ tagForChildren: tagForChildren,
onTap: onTap,
onLongPress: onLongPress,
onScrollLeft: onScrollLeft,
@@ -7060,6 +7066,7 @@
hintOverrides: properties.hintOverrides,
textDirection: _getTextDirection(context),
sortKey: properties.sortKey,
+ tagForChildren: properties.tagForChildren,
onTap: properties.onTap,
onLongPress: properties.onLongPress,
onScrollLeft: properties.onScrollLeft,
@@ -7131,6 +7138,7 @@
..namesRoute = properties.namesRoute
..textDirection = _getTextDirection(context)
..sortKey = properties.sortKey
+ ..tagForChildren = properties.tagForChildren
..onTap = properties.onTap
..onLongPress = properties.onLongPress
..onScrollLeft = properties.onScrollLeft
diff --git a/packages/flutter/test/widgets/semantics_test.dart b/packages/flutter/test/widgets/semantics_test.dart
index 314f74f..1c4aa2a 100644
--- a/packages/flutter/test/widgets/semantics_test.dart
+++ b/packages/flutter/test/widgets/semantics_test.dart
@@ -387,6 +387,54 @@
semantics.dispose();
});
+ testWidgets('Semantics tagForChildren works', (WidgetTester tester) async {
+ final SemanticsTester semantics = SemanticsTester(tester);
+
+ await tester.pumpWidget(
+ Directionality(
+ textDirection: TextDirection.ltr,
+ child: Semantics(
+ container: true,
+ tagForChildren: const SemanticsTag('custom tag'),
+ child: Column(
+ children: <Widget>[
+ Semantics(
+ container: true,
+ child: const Text('child 1'),
+ ),
+ Semantics(
+ container: true,
+ child: const Text('child 2'),
+ ),
+ ],
+ ),
+ ),
+ ),
+ );
+
+ final TestSemantics expectedSemantics = TestSemantics.root(
+ children: <TestSemantics>[
+ TestSemantics.rootChild(
+ children: <TestSemantics>[
+ TestSemantics(
+ label: 'child 1',
+ tags: <SemanticsTag>[const SemanticsTag('custom tag')],
+ textDirection: TextDirection.ltr,
+ ),
+ TestSemantics(
+ label: 'child 2',
+ tags: <SemanticsTag>[const SemanticsTag('custom tag')],
+ textDirection: TextDirection.ltr,
+ ),
+ ]
+ ),
+ ],
+ );
+
+ expect(semantics, hasSemantics(expectedSemantics, ignoreTransform: true, ignoreRect: true, ignoreId: true));
+ semantics.dispose();
+ });
+
testWidgets('Semantics widget supports all actions', (WidgetTester tester) async {
final SemanticsTester semantics = SemanticsTester(tester);
diff --git a/packages/flutter/test/widgets/text_test.dart b/packages/flutter/test/widgets/text_test.dart
index d1edba2..5065624 100644
--- a/packages/flutter/test/widgets/text_test.dart
+++ b/packages/flutter/test/widgets/text_test.dart
@@ -1039,6 +1039,176 @@
],
)));
}, semanticsEnabled: true, skip: isBrowser); // Browser semantics have different sizes.
+
+ // Regression test for https://github.com/flutter/flutter/issues/69787
+ testWidgets('WidgetSpans with no semantic information are elided from semantics - case 2', (WidgetTester tester) async {
+ final SemanticsTester semantics = SemanticsTester(tester);
+ await tester.pumpWidget(
+ Directionality(
+ textDirection: TextDirection.ltr,
+ child: RichText(
+ text: TextSpan(children: <InlineSpan>[
+ const WidgetSpan(child: SizedBox.shrink()),
+ const WidgetSpan(child: Text('included')),
+ TextSpan(
+ text: 'HELLO',
+ style: const TextStyle(color: Colors.black),
+ recognizer: TapGestureRecognizer()..onTap = () {},
+ ),
+ const WidgetSpan(child: Text('included2')),
+ ]),
+ ),
+ )
+ );
+
+ expect(semantics, hasSemantics(TestSemantics.root(
+ children: <TestSemantics>[
+ TestSemantics(
+ children: <TestSemantics>[
+ TestSemantics(label: 'included'),
+ TestSemantics(
+ label: 'HELLO',
+ actions: <SemanticsAction>[
+ SemanticsAction.tap,
+ ],
+ flags: <SemanticsFlag>[
+ SemanticsFlag.isLink,
+ ],
+ ),
+ TestSemantics(label: 'included2'),
+ ],
+ ),
+ ],
+ ),
+ ignoreId: true,
+ ignoreRect: true,
+ ignoreTransform: true,
+ ));
+ }, semanticsEnabled: true, skip: isBrowser); // Browser does not support widget span.
+
+ // Regression test for https://github.com/flutter/flutter/issues/69787
+ testWidgets('WidgetSpans with no semantic information are elided from semantics - case 3', (WidgetTester tester) async {
+ final SemanticsTester semantics = SemanticsTester(tester);
+ await tester.pumpWidget(
+ Directionality(
+ textDirection: TextDirection.ltr,
+ child: RichText(
+ text: TextSpan(children: <InlineSpan>[
+ const WidgetSpan(child: SizedBox.shrink()),
+ WidgetSpan(
+ child: Row(
+ children: <Widget>[
+ Semantics(
+ container: true,
+ child: const Text('foo'),
+ ),
+ Semantics(
+ container: true,
+ child: const Text('bar'),
+ ),
+ ],
+ ),
+ ),
+ TextSpan(
+ text: 'HELLO',
+ style: const TextStyle(color: Colors.black),
+ recognizer: TapGestureRecognizer()..onTap = () {},
+ ),
+ ]),
+ ),
+ )
+ );
+
+ expect(semantics, hasSemantics(TestSemantics.root(
+ children: <TestSemantics>[
+ TestSemantics(
+ children: <TestSemantics>[
+ TestSemantics(label: 'foo'),
+ TestSemantics(label: 'bar'),
+ TestSemantics(
+ label: 'HELLO',
+ actions: <SemanticsAction>[
+ SemanticsAction.tap,
+ ],
+ flags: <SemanticsFlag>[
+ SemanticsFlag.isLink,
+ ],
+ ),
+ ],
+ ),
+ ],
+ ),
+ ignoreId: true,
+ ignoreRect: true,
+ ignoreTransform: true,
+ ));
+ }, semanticsEnabled: true, skip: isBrowser); // Browser does not support widget span.
+
+ // Regression test for https://github.com/flutter/flutter/issues/69787
+ testWidgets('WidgetSpans with no semantic information are elided from semantics - case 4', (WidgetTester tester) async {
+ final SemanticsTester semantics = SemanticsTester(tester);
+ await tester.pumpWidget(
+ Directionality(
+ textDirection: TextDirection.ltr,
+ child: Center(
+ child: ClipRect(
+ child: Container(
+ color: Colors.green,
+ height: 100,
+ width: 100,
+ child: OverflowBox(
+ alignment: Alignment.topLeft,
+ maxWidth: double.infinity,
+ child: RichText(
+ text: TextSpan(
+ children: <InlineSpan>[
+ const WidgetSpan(
+ child: Icon(
+ Icons.edit,
+ size: 16,
+ semanticLabel: 'not clipped',
+ ),
+ ),
+ TextSpan(
+ text: 'next WS is clipped',
+ recognizer: TapGestureRecognizer()..onTap = () { },
+ ),
+ const WidgetSpan(
+ child: Icon(
+ Icons.edit,
+ size: 16,
+ semanticLabel: 'clipped',
+ ),
+ ),
+ ],
+ ),
+ ),
+ ),
+ ),
+ ),
+ ),
+ )
+ );
+
+ expect(semantics, hasSemantics(TestSemantics.root(
+ children: <TestSemantics>[
+ TestSemantics(
+ children: <TestSemantics>[
+ TestSemantics(label: 'not clipped'),
+ TestSemantics(
+ label: 'next WS is clipped',
+ flags: <SemanticsFlag>[SemanticsFlag.isLink],
+ actions: <SemanticsAction>[SemanticsAction.tap],
+ ),
+ ],
+ ),
+ ],
+ ),
+ ignoreId: true,
+ ignoreRect: true,
+ ignoreTransform: true,
+ ));
+ }, semanticsEnabled: true, skip: isBrowser); // Browser does not support widget span
}
Future<void> _pumpTextWidget({
