blob: eb2718fbd0543b8bd13facbdc2236de7edfa0562 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/gestures.dart' show DragStartBehavior;
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_test/flutter_test.dart';
class Leaf extends StatefulWidget {
const Leaf({ required Key key, required this.child }) : super(key: key);
final Widget child;
@override
State<Leaf> createState() => _LeafState();
}
class _LeafState extends State<Leaf> {
bool _keepAlive = false;
KeepAliveHandle? _handle;
@override
void deactivate() {
_handle?.release();
_handle = null;
super.deactivate();
}
void setKeepAlive(bool value) {
_keepAlive = value;
if (_keepAlive) {
if (_handle == null) {
_handle = KeepAliveHandle();
KeepAliveNotification(_handle!).dispatch(context);
}
} else {
_handle?.release();
_handle = null;
}
}
@override
Widget build(BuildContext context) {
if (_keepAlive && _handle == null) {
_handle = KeepAliveHandle();
KeepAliveNotification(_handle!).dispatch(context);
}
return widget.child;
}
}
List<Widget> generateList(Widget child, { required bool impliedMode }) {
return List<Widget>.generate(
100,
(int index) {
final Widget result = Leaf(
key: GlobalObjectKey<_LeafState>(index),
child: child,
);
if (impliedMode) {
return result;
}
return AutomaticKeepAlive(child: result);
},
growable: false,
);
}
void tests({ required bool impliedMode }) {
testWidgets('AutomaticKeepAlive with ListView with itemExtent', (WidgetTester tester) async {
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
addAutomaticKeepAlives: impliedMode,
addRepaintBoundaries: impliedMode,
addSemanticIndexes: false,
itemExtent: 12.3, // about 50 widgets visible
cacheExtent: 0.0,
children: generateList(const Placeholder(), impliedMode: impliedMode),
),
),
);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
await tester.drag(find.byType(ListView), const Offset(0.0, -300.0)); // about 25 widgets' worth
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(60).currentState!.setKeepAlive(true);
await tester.drag(find.byType(ListView), const Offset(0.0, 300.0)); // back to top
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(60).currentState!.setKeepAlive(false);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
});
testWidgets('AutomaticKeepAlive with ListView without itemExtent', (WidgetTester tester) async {
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
addAutomaticKeepAlives: impliedMode,
addRepaintBoundaries: impliedMode,
addSemanticIndexes: false,
cacheExtent: 0.0,
children: generateList(
const SizedBox(height: 12.3, child: Placeholder()), // about 50 widgets visible
impliedMode: impliedMode,
),
),
),
);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
await tester.drag(find.byType(ListView), const Offset(0.0, -300.0)); // about 25 widgets' worth
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(60).currentState!.setKeepAlive(true);
await tester.drag(find.byType(ListView), const Offset(0.0, 300.0)); // back to top
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(60).currentState!.setKeepAlive(false);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
});
testWidgets('AutomaticKeepAlive with GridView', (WidgetTester tester) async {
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: GridView.count(
addAutomaticKeepAlives: impliedMode,
addRepaintBoundaries: impliedMode,
addSemanticIndexes: false,
crossAxisCount: 2,
childAspectRatio: 400.0 / 24.6, // about 50 widgets visible
cacheExtent: 0.0,
children: generateList(
const Placeholder(),
impliedMode: impliedMode,
),
),
),
);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
await tester.drag(find.byType(GridView), const Offset(0.0, -300.0)); // about 25 widgets' worth
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(60).currentState!.setKeepAlive(true);
await tester.drag(find.byType(GridView), const Offset(0.0, 300.0)); // back to top
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(60).currentState!.setKeepAlive(false);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(30)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(59), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(60), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(61), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(90), skipOffstage: false), findsNothing);
});
}
void main() {
group('Explicit automatic keep-alive', () { tests(impliedMode: false); });
group('Implied automatic keep-alive', () { tests(impliedMode: true); });
testWidgets('AutomaticKeepAlive double', (WidgetTester tester) async {
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
addAutomaticKeepAlives: false,
addRepaintBoundaries: false,
addSemanticIndexes: false,
cacheExtent: 0.0,
children: const <Widget>[
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(0), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(1), child: Placeholder()),
]),
),
),
AutomaticKeepAlive(
child: SizedBox(
key: GlobalObjectKey<_LeafState>(2),
height: 400.0,
),
),
AutomaticKeepAlive(
child: SizedBox(
key: GlobalObjectKey<_LeafState>(3),
height: 400.0,
),
),
],
),
),
);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3), skipOffstage: false), findsNothing);
await tester.drag(find.byType(ListView), const Offset(0.0, -1000.0)); // move to bottom
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
await tester.drag(find.byType(ListView), const Offset(0.0, 1000.0)); // move to top
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(0).currentState!.setKeepAlive(true);
await tester.drag(find.byType(ListView), const Offset(0.0, -1000.0)); // move to bottom
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
const GlobalObjectKey<_LeafState>(1).currentState!.setKeepAlive(true);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
const GlobalObjectKey<_LeafState>(0).currentState!.setKeepAlive(false);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
const GlobalObjectKey<_LeafState>(1).currentState!.setKeepAlive(false);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
});
testWidgets('AutomaticKeepAlive double 2', (WidgetTester tester) async {
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
addAutomaticKeepAlives: false,
addRepaintBoundaries: false,
addSemanticIndexes: false,
cacheExtent: 0.0,
children: const <Widget>[
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(0), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(1), child: Placeholder()),
]),
),
),
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(2), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(3), child: Placeholder()),
]),
),
),
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(4), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(5), child: Placeholder()),
]),
),
),
],
),
),
);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5), skipOffstage: false), findsNothing);
const GlobalObjectKey<_LeafState>(0).currentState!.setKeepAlive(true);
await tester.drag(find.byType(ListView), const Offset(0.0, -1000.0)); // move to bottom
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5)), findsOneWidget);
await tester.pumpWidget(Directionality(
textDirection: TextDirection.ltr,
child: ListView(
addAutomaticKeepAlives: false,
addRepaintBoundaries: false,
addSemanticIndexes: false,
cacheExtent: 0.0,
children: const <Widget>[
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(1), child: Placeholder()),
]),
),
),
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(2), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(3), child: Placeholder()),
]),
),
),
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(4), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(5), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(0), child: Placeholder()),
]),
),
),
],
),
));
await tester.pump(); // Sometimes AutomaticKeepAlive needs an extra pump to clean things up.
expect(find.byKey(const GlobalObjectKey<_LeafState>(1), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsOneWidget);
await tester.drag(find.byType(ListView), const Offset(0.0, 1000.0)); // move to top
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5)), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0)), findsNothing);
const GlobalObjectKey<_LeafState>(0).currentState!.setKeepAlive(false);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsNothing);
await tester.pumpWidget(Directionality(
textDirection: TextDirection.ltr,
child: ListView(
addAutomaticKeepAlives: false,
addRepaintBoundaries: false,
addSemanticIndexes: false,
cacheExtent: 0.0,
children: const <Widget>[
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(1), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(2), child: Placeholder()),
]),
),
),
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(),
),
),
AutomaticKeepAlive(
child: SizedBox(
height: 400.0,
child: Stack(children: <Widget>[
Leaf(key: GlobalObjectKey<_LeafState>(3), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(4), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(5), child: Placeholder()),
Leaf(key: GlobalObjectKey<_LeafState>(0), child: Placeholder()),
]),
),
),
],
),
));
await tester.pump(); // Sometimes AutomaticKeepAlive needs an extra pump to clean things up.
expect(find.byKey(const GlobalObjectKey<_LeafState>(1)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(2)), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_LeafState>(3), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(4), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(5), skipOffstage: false), findsNothing);
expect(find.byKey(const GlobalObjectKey<_LeafState>(0), skipOffstage: false), findsNothing);
});
testWidgets('AutomaticKeepAlive with keepAlive set to true before initState', (WidgetTester tester) async {
await tester.pumpWidget(Directionality(
textDirection: TextDirection.ltr,
child: ListView.builder(
dragStartBehavior: DragStartBehavior.down,
addSemanticIndexes: false,
itemCount: 50,
itemBuilder: (BuildContext context, int index) {
if (index == 0) {
return const _AlwaysKeepAlive(
key: GlobalObjectKey<_AlwaysKeepAliveState>(0),
);
}
return SizedBox(
height: 44.0,
child: Text('FooBar $index'),
);
},
),
));
expect(find.text('keep me alive'), findsOneWidget);
expect(find.text('FooBar 1'), findsOneWidget);
expect(find.text('FooBar 2'), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_AlwaysKeepAliveState>(0)), findsOneWidget);
await tester.drag(find.byType(ListView), const Offset(0.0, -1000.0)); // move to bottom
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_AlwaysKeepAliveState>(0), skipOffstage: false), findsOneWidget);
expect(find.text('keep me alive', skipOffstage: false), findsOneWidget);
expect(find.text('FooBar 1'), findsNothing);
expect(find.text('FooBar 2'), findsNothing);
});
testWidgets('AutomaticKeepAlive with keepAlive set to true before initState and widget goes out of scope', (WidgetTester tester) async {
await tester.pumpWidget(Directionality(
textDirection: TextDirection.ltr,
child: ListView.builder(
addSemanticIndexes: false,
itemCount: 250,
itemBuilder: (BuildContext context, int index) {
if (index.isEven) {
return _AlwaysKeepAlive(
key: GlobalObjectKey<_AlwaysKeepAliveState>(index),
);
}
return SizedBox(
height: 44.0,
child: Text('FooBar $index'),
);
},
),
));
expect(find.text('keep me alive'), findsNWidgets(7));
expect(find.text('FooBar 1'), findsOneWidget);
expect(find.text('FooBar 3'), findsOneWidget);
expect(find.byKey(const GlobalObjectKey<_AlwaysKeepAliveState>(0)), findsOneWidget);
final ScrollableState state = tester.state(find.byType(Scrollable));
final ScrollPosition position = state.position;
position.jumpTo(3025.0);
await tester.pump();
expect(find.byKey(const GlobalObjectKey<_AlwaysKeepAliveState>(0), skipOffstage: false), findsOneWidget);
expect(find.text('keep me alive', skipOffstage: false), findsNWidgets(23));
expect(find.text('FooBar 1'), findsNothing);
expect(find.text('FooBar 3'), findsNothing);
expect(find.text('FooBar 73'), findsOneWidget);
});
testWidgets('AutomaticKeepAlive with SliverKeepAliveWidget', (WidgetTester tester) async {
// We're just doing a basic test here to make sure that the functionality of
// RenderSliverWithKeepAliveMixin doesn't get regressed or deleted. As testing
// the full functionality would be cumbersome.
final RenderSliverMultiBoxAdaptorAlt alternate = RenderSliverMultiBoxAdaptorAlt();
final RenderBox child = RenderBoxKeepAlive();
alternate.insert(child);
expect(alternate.children.length, 1);
});
testWidgets('Keep alive Listenable has its listener removed once called', (WidgetTester tester) async {
final LeakCheckerHandle handle = LeakCheckerHandle();
await tester.pumpWidget(Directionality(
textDirection: TextDirection.ltr,
child: ListView.builder(
itemCount: 1,
itemBuilder: (BuildContext context, int index) {
return const KeepAliveListenableLeakChecker(key: GlobalObjectKey<_KeepAliveListenableLeakCheckerState>(0));
},
),
));
final _KeepAliveListenableLeakCheckerState state = const GlobalObjectKey<_KeepAliveListenableLeakCheckerState>(0).currentState!;
expect(handle.hasListeners, false);
state.dispatch(handle);
expect(handle.hasListeners, true);
handle.notifyListeners();
expect(handle.hasListeners, false);
});
}
class _AlwaysKeepAlive extends StatefulWidget {
const _AlwaysKeepAlive({ required Key key }) : super(key: key);
@override
State<StatefulWidget> createState() => _AlwaysKeepAliveState();
}
class _AlwaysKeepAliveState extends State<_AlwaysKeepAlive> with AutomaticKeepAliveClientMixin<_AlwaysKeepAlive> {
@override
bool get wantKeepAlive => true;
@override
Widget build(BuildContext context) {
super.build(context);
return const SizedBox(
height: 48.0,
child: Text('keep me alive'),
);
}
}
class RenderBoxKeepAlive extends RenderBox { }
mixin KeepAliveParentDataMixinAlt implements KeepAliveParentDataMixin {
@override
bool keptAlive = false;
@override
bool keepAlive = false;
}
class RenderSliverMultiBoxAdaptorAlt extends RenderSliver with
KeepAliveParentDataMixinAlt,
RenderSliverHelpers,
RenderSliverWithKeepAliveMixin {
final List<RenderBox> children = <RenderBox>[];
void insert(RenderBox child, { RenderBox? after }) {
children.add(child);
}
@override
void visitChildren(RenderObjectVisitor visitor) {
children.forEach(visitor);
}
@override
void performLayout() { }
}
class LeakCheckerHandle with ChangeNotifier {
@override
bool get hasListeners => super.hasListeners;
}
class KeepAliveListenableLeakChecker extends StatefulWidget {
const KeepAliveListenableLeakChecker({super.key});
@override
State<KeepAliveListenableLeakChecker> createState() => _KeepAliveListenableLeakCheckerState();
}
class _KeepAliveListenableLeakCheckerState extends State<KeepAliveListenableLeakChecker> {
void dispatch(Listenable handle) {
KeepAliveNotification(handle).dispatch(context);
}
@override
Widget build(BuildContext context) {
return const Placeholder();
}
}