8a6e973739
`RenderSemanticsGestureHandler` is no longer a semantics boundary, which allows us to correctly mark disabled buttons as disabled without having their semantics size and semantics node id change unexpectedly. Fixes https://github.com/flutter/flutter/issues/12589. Fixes https://github.com/flutter/flutter/issues/11991. See also https://github.com/flutter/flutter/issues/11993. This change also required some refactoring to how we deal with `twoPaneSemantics` scrolling as it previously relied on `RenderSemanticsGestureHandler` being a semantics boundary. This should also make the underlying logic easier to understand. In addition, the following minor changes are included in this PR: * Removal of orphaned and unused `SemanticsConfiguration.isMergingDescendantsIntoOneNode`. * Logic optimizations for `markNeedsSemanticsUpdate` . * Fix for edge case where `MergeSemantics` failed to merge semantics. * Use of emojis to better indicate leaf merging in the printed semantics tree. * Better assert message for adding invisible child semantics nodes. * Make some semantics tests robuster by not relying on creation order of SemanticsNode ids across test boundaries. Fixes https://github.com/flutter/flutter/issues/13943.
444 lines
24 KiB
Dart
444 lines
24 KiB
Dart
// Copyright 2017 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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import 'dart:io' show Platform;
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import 'package:flutter_test/flutter_test.dart';
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import 'package:flutter/widgets.dart';
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class Leaf extends StatefulWidget {
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const Leaf({ Key key, this.child }) : super(key: key);
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final Widget child;
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@override
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_LeafState createState() => new _LeafState();
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}
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class _LeafState extends State<Leaf> {
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bool _keepAlive = false;
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void setKeepAlive(bool value) {
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setState(() { _keepAlive = value; });
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}
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@override
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Widget build(BuildContext context) {
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return new KeepAlive(
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keepAlive: _keepAlive,
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child: widget.child,
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);
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}
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}
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List<Widget> generateList(Widget child) {
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return new List<Widget>.generate(
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100,
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(int index) => new Leaf(
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key: new GlobalObjectKey<_LeafState>(index),
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child: child,
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),
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growable: false,
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);
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}
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void main() {
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testWidgets('KeepAlive with ListView with itemExtent', (WidgetTester tester) async {
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await tester.pumpWidget(
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new Directionality(
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textDirection: TextDirection.ltr,
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child: new ListView(
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addAutomaticKeepAlives: false,
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addRepaintBoundaries: false,
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itemExtent: 12.3, // about 50 widgets visible
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children: generateList(const Placeholder()),
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),
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),
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);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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await tester.drag(find.byType(ListView), const Offset(0.0, -300.0)); // about 25 widgets' worth
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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const GlobalObjectKey<_LeafState>(60).currentState.setKeepAlive(true);
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await tester.drag(find.byType(ListView), const Offset(0.0, 300.0)); // back to top
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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const GlobalObjectKey<_LeafState>(60).currentState.setKeepAlive(false);
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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});
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testWidgets('KeepAlive with ListView without itemExtent', (WidgetTester tester) async {
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await tester.pumpWidget(
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new Directionality(
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textDirection: TextDirection.ltr,
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child: new ListView(
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addAutomaticKeepAlives: false,
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addRepaintBoundaries: false,
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children: generateList(new Container(height: 12.3, child: const Placeholder())), // about 50 widgets visible
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),
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),
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);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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await tester.drag(find.byType(ListView), const Offset(0.0, -300.0)); // about 25 widgets' worth
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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const GlobalObjectKey<_LeafState>(60).currentState.setKeepAlive(true);
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await tester.drag(find.byType(ListView), const Offset(0.0, 300.0)); // back to top
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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const GlobalObjectKey<_LeafState>(60).currentState.setKeepAlive(false);
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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});
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testWidgets('KeepAlive with GridView', (WidgetTester tester) async {
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await tester.pumpWidget(
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new Directionality(
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textDirection: TextDirection.ltr,
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child: new GridView.count(
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addAutomaticKeepAlives: false,
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addRepaintBoundaries: false,
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crossAxisCount: 2,
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childAspectRatio: 400.0 / 24.6, // about 50 widgets visible
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children: generateList(new Container(child: const Placeholder())),
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),
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),
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);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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await tester.drag(find.byType(GridView), const Offset(0.0, -300.0)); // about 25 widgets' worth
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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const GlobalObjectKey<_LeafState>(60).currentState.setKeepAlive(true);
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await tester.drag(find.byType(GridView), const Offset(0.0, 300.0)); // back to top
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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const GlobalObjectKey<_LeafState>(60).currentState.setKeepAlive(false);
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await tester.pump();
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expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsNothing);
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expect(find.byKey(const GlobalObjectKey<_LeafState>(90)), findsNothing);
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});
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testWidgets('KeepAlive render tree description', (WidgetTester tester) async {
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await tester.pumpWidget(
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new Directionality(
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textDirection: TextDirection.ltr,
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child: new ListView(
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addAutomaticKeepAlives: false,
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addRepaintBoundaries: false,
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itemExtent: 400.0, // 2 visible children
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children: generateList(const Placeholder()),
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),
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),
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);
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// The important lines below are the ones marked with "<----"
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expect(tester.binding.renderView.toStringDeep(minLevel: DiagnosticLevel.info), equalsIgnoringHashCodes(
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'RenderView#00000\n'
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' │ debug mode enabled - ${Platform.operatingSystem}\n'
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' │ window size: Size(2400.0, 1800.0) (in physical pixels)\n'
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' │ device pixel ratio: 3.0 (physical pixels per logical pixel)\n'
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' │ configuration: Size(800.0, 600.0) at 3.0x (in logical pixels)\n'
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' │\n'
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' └─child: RenderRepaintBoundary#00000\n'
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' │ parentData: <none>\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ layer: OffsetLayer#00000\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ metrics: 0.0% useful (1 bad vs 0 good)\n'
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' │ diagnosis: insufficient data to draw conclusion (less than five\n'
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' │ repaints)\n'
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' │\n'
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' └─child: RenderCustomPaint#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │\n'
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' └─child: RenderRepaintBoundary#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ layer: OffsetLayer#00000\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ metrics: 0.0% useful (1 bad vs 0 good)\n'
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' │ diagnosis: insufficient data to draw conclusion (less than five\n'
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' │ repaints)\n'
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' │\n'
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' └─child: _RenderExcludableScrollSemantics#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ semantic boundary\n'
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' │ size: Size(800.0, 600.0)\n'
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' │\n'
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' └─child: RenderSemanticsGestureHandler#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ gestures: vertical scroll\n'
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' │\n'
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' └─child: RenderPointerListener#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ behavior: opaque\n'
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' │ listeners: down\n'
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' │\n'
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' └─child: RenderSemanticsAnnotations#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │\n'
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' └─child: RenderIgnorePointer#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ ignoring: false\n'
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' │ ignoringSemantics: false\n'
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' │\n'
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' └─child: RenderViewport#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ layer: OffsetLayer#00000\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ axisDirection: down\n'
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' │ crossAxisDirection: right\n'
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' │ offset: ScrollPositionWithSingleContext#00000(offset: 0.0, range:\n'
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' │ 0.0..39400.0, viewport: 600.0, ScrollableState,\n'
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' │ AlwaysScrollableScrollPhysics -> ClampingScrollPhysics,\n'
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' │ IdleScrollActivity#00000, ScrollDirection.idle)\n'
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' │ anchor: 0.0\n'
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' │\n'
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' └─center child: RenderSliverFixedExtentList#00000 relayoutBoundary=up1\n'
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' │ parentData: paintOffset=Offset(0.0, 0.0) (can use size)\n'
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' │ constraints: SliverConstraints(AxisDirection.down,\n'
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' │ GrowthDirection.forward, ScrollDirection.idle, scrollOffset:\n'
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' │ 0.0, remainingPaintExtent: 600.0, crossAxisExtent: 800.0,\n'
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' │ crossAxisDirection: AxisDirection.right,\n'
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' │ viewportMainAxisExtent: 600.0)\n'
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' │ geometry: SliverGeometry(scrollExtent: 40000.0, paintExtent:\n'
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' │ 600.0, maxPaintExtent: 40000.0, hasVisualOverflow: true)\n'
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' │ currently live children: 0 to 1\n'
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' │\n'
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' ├─child with index 0: RenderLimitedBox#00000\n'
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' │ │ parentData: index=0; layoutOffset=0.0\n'
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' │ │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
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' │ │ size: Size(800.0, 400.0)\n'
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' │ │ maxWidth: 400.0\n'
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' │ │ maxHeight: 400.0\n'
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' │ │\n'
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' │ └─child: RenderCustomPaint#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
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' │ size: Size(800.0, 400.0)\n'
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' │\n'
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' └─child with index 1: RenderLimitedBox#00000\n' // <----- no dashed line starts here
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' │ parentData: index=1; layoutOffset=400.0\n'
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' │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
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' │ size: Size(800.0, 400.0)\n'
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' │ maxWidth: 400.0\n'
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' │ maxHeight: 400.0\n'
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' │\n'
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' └─child: RenderCustomPaint#00000\n'
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' parentData: <none> (can use size)\n'
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' constraints: BoxConstraints(w=800.0, h=400.0)\n'
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' size: Size(800.0, 400.0)\n'
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));
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const GlobalObjectKey<_LeafState>(0).currentState.setKeepAlive(true);
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await tester.drag(find.byType(ListView), const Offset(0.0, -1000.0));
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await tester.pump();
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const GlobalObjectKey<_LeafState>(3).currentState.setKeepAlive(true);
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await tester.drag(find.byType(ListView), const Offset(0.0, -1000.0));
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await tester.pump();
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expect(tester.binding.renderView.toStringDeep(minLevel: DiagnosticLevel.info), equalsIgnoringHashCodes(
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'RenderView#00000\n'
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' │ debug mode enabled - ${Platform.operatingSystem}\n'
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' │ window size: Size(2400.0, 1800.0) (in physical pixels)\n'
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' │ device pixel ratio: 3.0 (physical pixels per logical pixel)\n'
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' │ configuration: Size(800.0, 600.0) at 3.0x (in logical pixels)\n'
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' │\n'
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' └─child: RenderRepaintBoundary#00000\n'
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' │ parentData: <none>\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ layer: OffsetLayer#00000\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ metrics: 0.0% useful (1 bad vs 0 good)\n'
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' │ diagnosis: insufficient data to draw conclusion (less than five\n'
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' │ repaints)\n'
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' │\n'
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' └─child: RenderCustomPaint#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │\n'
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' └─child: RenderRepaintBoundary#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ layer: OffsetLayer#00000\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ metrics: 0.0% useful (1 bad vs 0 good)\n'
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' │ diagnosis: insufficient data to draw conclusion (less than five\n'
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' │ repaints)\n'
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' │\n'
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' └─child: _RenderExcludableScrollSemantics#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ semantic boundary\n'
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' │ size: Size(800.0, 600.0)\n'
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' │\n'
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' └─child: RenderSemanticsGestureHandler#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ gestures: vertical scroll\n'
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' │\n'
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' └─child: RenderPointerListener#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
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' │ size: Size(800.0, 600.0)\n'
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' │ behavior: opaque\n'
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' │ listeners: down\n'
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' │\n'
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' └─child: RenderSemanticsAnnotations#00000\n'
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' │ parentData: <none> (can use size)\n'
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' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
|
|
' │ size: Size(800.0, 600.0)\n'
|
|
' │\n'
|
|
' └─child: RenderIgnorePointer#00000\n'
|
|
' │ parentData: <none> (can use size)\n'
|
|
' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
|
|
' │ size: Size(800.0, 600.0)\n'
|
|
' │ ignoring: false\n'
|
|
' │ ignoringSemantics: false\n'
|
|
' │\n'
|
|
' └─child: RenderViewport#00000\n'
|
|
' │ parentData: <none> (can use size)\n'
|
|
' │ constraints: BoxConstraints(w=800.0, h=600.0)\n'
|
|
' │ layer: OffsetLayer#00000\n'
|
|
' │ size: Size(800.0, 600.0)\n'
|
|
' │ axisDirection: down\n'
|
|
' │ crossAxisDirection: right\n'
|
|
' │ offset: ScrollPositionWithSingleContext#00000(offset: 2000.0,\n'
|
|
' │ range: 0.0..39400.0, viewport: 600.0, ScrollableState,\n'
|
|
' │ AlwaysScrollableScrollPhysics -> ClampingScrollPhysics,\n'
|
|
' │ IdleScrollActivity#00000, ScrollDirection.idle)\n'
|
|
' │ anchor: 0.0\n'
|
|
' │\n'
|
|
' └─center child: RenderSliverFixedExtentList#00000 relayoutBoundary=up1\n'
|
|
' │ parentData: paintOffset=Offset(0.0, 0.0) (can use size)\n'
|
|
' │ constraints: SliverConstraints(AxisDirection.down,\n'
|
|
' │ GrowthDirection.forward, ScrollDirection.idle, scrollOffset:\n'
|
|
' │ 2000.0, remainingPaintExtent: 600.0, crossAxisExtent: 800.0,\n'
|
|
' │ crossAxisDirection: AxisDirection.right,\n'
|
|
' │ viewportMainAxisExtent: 600.0)\n'
|
|
' │ geometry: SliverGeometry(scrollExtent: 40000.0, paintExtent:\n'
|
|
' │ 600.0, maxPaintExtent: 40000.0, hasVisualOverflow: true)\n'
|
|
' │ currently live children: 5 to 6\n'
|
|
' │\n'
|
|
' ├─child with index 5: RenderLimitedBox#00000\n' // <----- this is index 5, not 0
|
|
' │ │ parentData: index=5; layoutOffset=2000.0\n'
|
|
' │ │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' │ │ size: Size(800.0, 400.0)\n'
|
|
' │ │ maxWidth: 400.0\n'
|
|
' │ │ maxHeight: 400.0\n'
|
|
' │ │\n'
|
|
' │ └─child: RenderCustomPaint#00000\n'
|
|
' │ parentData: <none> (can use size)\n'
|
|
' │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' │ size: Size(800.0, 400.0)\n'
|
|
' │\n'
|
|
' ├─child with index 6: RenderLimitedBox#00000\n'
|
|
' ╎ │ parentData: index=6; layoutOffset=2400.0\n'
|
|
' ╎ │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' ╎ │ size: Size(800.0, 400.0)\n'
|
|
' ╎ │ maxWidth: 400.0\n'
|
|
' ╎ │ maxHeight: 400.0\n'
|
|
' ╎ │\n'
|
|
' ╎ └─child: RenderCustomPaint#00000\n'
|
|
' ╎ parentData: <none> (can use size)\n'
|
|
' ╎ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' ╎ size: Size(800.0, 400.0)\n'
|
|
' ╎\n'
|
|
' ╎╌child with index 0 (kept alive offstage): RenderLimitedBox#00000\n' // <----- this one is index 0 and is marked as being offstage
|
|
' ╎ │ parentData: index=0; keepAlive; layoutOffset=0.0\n'
|
|
' ╎ │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' ╎ │ size: Size(800.0, 400.0)\n'
|
|
' ╎ │ maxWidth: 400.0\n'
|
|
' ╎ │ maxHeight: 400.0\n'
|
|
' ╎ │\n'
|
|
' ╎ └─child: RenderCustomPaint#00000\n'
|
|
' ╎ parentData: <none> (can use size)\n'
|
|
' ╎ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' ╎ size: Size(800.0, 400.0)\n'
|
|
' ╎\n' // <----- dashed line ends here
|
|
' └╌child with index 3 (kept alive offstage): RenderLimitedBox#00000\n'
|
|
' │ parentData: index=3; keepAlive; layoutOffset=1200.0\n'
|
|
' │ constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' │ size: Size(800.0, 400.0)\n'
|
|
' │ maxWidth: 400.0\n'
|
|
' │ maxHeight: 400.0\n'
|
|
' │\n'
|
|
' └─child: RenderCustomPaint#00000\n'
|
|
' parentData: <none> (can use size)\n'
|
|
' constraints: BoxConstraints(w=800.0, h=400.0)\n'
|
|
' size: Size(800.0, 400.0)\n'
|
|
));
|
|
});
|
|
|
|
}
|