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// 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/rendering.dart';
import 'package:flutter/services.dart';
import 'package:flutter/src/widgets/basic.dart';
import 'package:flutter/src/widgets/framework.dart';
import 'package:flutter/src/widgets/layout_builder.dart';
import 'package:flutter/src/widgets/media_query.dart';
import 'package:flutter/src/widgets/scroll_view.dart';
import 'package:flutter/src/widgets/sliver_layout_builder.dart';
import 'package:flutter_test/flutter_test.dart';
class Wrapper extends StatelessWidget {
const Wrapper({
super.key,
required this.child,
}) : assert(child != null);
final Widget child;
@override
Widget build(BuildContext context) => child;
}
void main() {
testWidgets('Moving a global key from another LayoutBuilder at layout time', (WidgetTester tester) async {
final GlobalKey victimKey = GlobalKey();
await tester.pumpWidget(Row(
textDirection: TextDirection.ltr,
children: <Widget>[
Wrapper(
child: LayoutBuilder(builder: (BuildContext context, BoxConstraints constraints) {
return const SizedBox();
}),
),
Wrapper(
child: Wrapper(
child: LayoutBuilder(builder: (BuildContext context, BoxConstraints constraints) {
return Wrapper(
child: SizedBox(key: victimKey),
);
}),
),
),
],
));
await tester.pumpWidget(Row(
textDirection: TextDirection.ltr,
children: <Widget>[
Wrapper(
child: LayoutBuilder(builder: (BuildContext context, BoxConstraints constraints) {
return Wrapper(
child: SizedBox(key: victimKey),
);
}),
),
Wrapper(
child: Wrapper(
child: LayoutBuilder(builder: (BuildContext context, BoxConstraints constraints) {
return const SizedBox();
}),
),
),
],
));
expect(tester.takeException(), null);
});
testWidgets('Moving a global key from another SliverLayoutBuilder at layout time', (WidgetTester tester) async {
final GlobalKey victimKey1 = GlobalKey();
final GlobalKey victimKey2 = GlobalKey();
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: CustomScrollView(
slivers: <Widget>[
SliverLayoutBuilder(
builder: (BuildContext context, SliverConstraints constraint) {
return SliverPadding(key: victimKey1, padding: const EdgeInsets.fromLTRB(1, 2, 3, 4));
},
),
SliverLayoutBuilder(
builder: (BuildContext context, SliverConstraints constraint) {
return SliverPadding(key: victimKey2, padding: const EdgeInsets.fromLTRB(5, 7, 11, 13));
},
),
SliverLayoutBuilder(
builder: (BuildContext context, SliverConstraints constraint) {
return const SliverPadding(padding: EdgeInsets.fromLTRB(5, 7, 11, 13));
},
),
],
),
),
);
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: CustomScrollView(
slivers: <Widget>[
SliverLayoutBuilder(
builder: (BuildContext context, SliverConstraints constraint) {
return SliverPadding(key: victimKey2, padding: const EdgeInsets.fromLTRB(1, 2, 3, 4));
},
),
SliverLayoutBuilder(
builder: (BuildContext context, SliverConstraints constraint) {
return const SliverPadding(padding: EdgeInsets.fromLTRB(5, 7, 11, 13));
},
),
SliverLayoutBuilder(
builder: (BuildContext context, SliverConstraints constraint) {
return SliverPadding(key: victimKey1, padding: const EdgeInsets.fromLTRB(5, 7, 11, 13));
},
),
],
),
),
);
expect(tester.takeException(), null);
});
testWidgets('LayoutBuilder does not layout twice', (WidgetTester tester) async {
// This widget marks itself dirty when the closest MediaQuery changes.
final _LayoutCount widget = _LayoutCount();
late StateSetter setState;
bool updated = false;
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: StatefulBuilder(
builder: (BuildContext context, StateSetter setter) {
setState = setter;
return MediaQuery(
data: updated
? const MediaQueryData(platformBrightness: Brightness.dark)
: const MediaQueryData(),
child: LayoutBuilder(
builder: (BuildContext context, BoxConstraints constraints) {
return Center(
child: SizedBox.square(
dimension: 20,
child: Center(
child: SizedBox.square(
dimension: updated ? 10 : 20,
child: widget,
),
),
),
);
},
),
);
}
),
),
);
assert(widget._renderObject.layoutCount == 1);
setState(() { updated = true; });
await tester.pump();
expect(widget._renderObject.layoutCount, 2);
});
}
class _LayoutCount extends LeafRenderObjectWidget {
late final _RenderLayoutCount _renderObject;
@override
RenderObject createRenderObject(BuildContext context) {
return _renderObject = _RenderLayoutCount(MediaQuery.of(context));
}
@override
void updateRenderObject(BuildContext context, _RenderLayoutCount renderObject) {
renderObject.mediaQuery = MediaQuery.of(context);
}
}
class _RenderLayoutCount extends RenderProxyBox {
_RenderLayoutCount(this._mediaQuery);
int layoutCount = 0;
MediaQueryData get mediaQuery => _mediaQuery;
MediaQueryData _mediaQuery;
set mediaQuery(MediaQueryData newValue) {
if (newValue != _mediaQuery) {
_mediaQuery = newValue;
markNeedsLayout();
}
}
@override
bool get sizedByParent => true;
@override
void performLayout() {
layoutCount += 1;
}
}