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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_test/flutter_test.dart';
import 'package:flutter/widgets.dart';
import 'states.dart';
void main() {
testWidgets('ScrollController control test', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(
height: 200.0,
child: Text(state),
);
}).toList(),
),
),
);
double realOffset() {
return tester.state<ScrollableState>(find.byType(Scrollable)).position.pixels;
}
expect(controller.offset, equals(0.0));
expect(realOffset(), equals(controller.offset));
controller.jumpTo(653.0);
expect(controller.offset, equals(653.0));
expect(realOffset(), equals(controller.offset));
await tester.pump();
expect(controller.offset, equals(653.0));
expect(realOffset(), equals(controller.offset));
controller.animateTo(326.0, duration: const Duration(milliseconds: 300), curve: Curves.ease);
await tester.pumpAndSettle(const Duration(milliseconds: 100));
expect(controller.offset, equals(326.0));
expect(realOffset(), equals(controller.offset));
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
key: const Key('second'),
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(
height: 200.0,
child: Text(state),
);
}).toList(),
),
),
);
expect(controller.offset, equals(0.0));
expect(realOffset(), equals(controller.offset));
controller.jumpTo(653.0);
expect(controller.offset, equals(653.0));
expect(realOffset(), equals(controller.offset));
final ScrollController controller2 = ScrollController();
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
key: const Key('second'),
controller: controller2,
children: kStates.map<Widget>((String state) {
return Container(
height: 200.0,
child: Text(state),
);
}).toList(),
),
),
);
expect(() => controller.offset, throwsAssertionError);
expect(controller2.offset, equals(653.0));
expect(realOffset(), equals(controller2.offset));
expect(() => controller.jumpTo(120.0), throwsAssertionError);
expect(() => controller.animateTo(132.0, duration: const Duration(milliseconds: 300), curve: Curves.ease), throwsAssertionError);
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
key: const Key('second'),
controller: controller2,
physics: const BouncingScrollPhysics(),
children: kStates.map<Widget>((String state) {
return Container(
height: 200.0,
child: Text(state),
);
}).toList(),
),
),
);
expect(controller2.offset, equals(653.0));
expect(realOffset(), equals(controller2.offset));
controller2.jumpTo(432.0);
expect(controller2.offset, equals(432.0));
expect(realOffset(), equals(controller2.offset));
await tester.pump();
expect(controller2.offset, equals(432.0));
expect(realOffset(), equals(controller2.offset));
});
testWidgets('ScrollController control test', (WidgetTester tester) async {
final ScrollController controller = ScrollController(
initialScrollOffset: 209.0,
);
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: GridView.count(
crossAxisCount: 4,
controller: controller,
children: kStates.map<Widget>((String state) => Text(state)).toList(),
),
),
);
double realOffset() {
return tester.state<ScrollableState>(find.byType(Scrollable)).position.pixels;
}
expect(controller.offset, equals(209.0));
expect(realOffset(), equals(controller.offset));
controller.jumpTo(105.0);
await tester.pump();
expect(controller.offset, equals(105.0));
expect(realOffset(), equals(controller.offset));
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: GridView.count(
crossAxisCount: 2,
controller: controller,
children: kStates.map<Widget>((String state) => Text(state)).toList(),
),
),
);
expect(controller.offset, equals(105.0));
expect(realOffset(), equals(controller.offset));
});
testWidgets('DrivenScrollActivity ending after dispose', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
controller: controller,
children: <Widget>[ Container(height: 200000.0) ],
),
),
);
controller.animateTo(1000.0, duration: const Duration(seconds: 1), curve: Curves.linear);
await tester.pump(); // Start the animation.
// We will now change the tree on the same frame as the animation ends.
await tester.pumpWidget(Container(), const Duration(seconds: 2));
});
testWidgets('Read operations on ScrollControllers with no positions fail', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
expect(() => controller.offset, throwsAssertionError);
expect(() => controller.position, throwsAssertionError);
});
testWidgets('Read operations on ScrollControllers with more than one position fail', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
children: <Widget>[
Container(
constraints: const BoxConstraints(maxHeight: 500.0),
child: ListView(
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(height: 200.0, child: Text(state));
}).toList(),
),
),
Container(
constraints: const BoxConstraints(maxHeight: 500.0),
child: ListView(
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(height: 200.0, child: Text(state));
}).toList(),
),
),
],
),
),
);
expect(() => controller.offset, throwsAssertionError);
expect(() => controller.position, throwsAssertionError);
});
testWidgets('Write operations on ScrollControllers with no positions fail', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
expect(() => controller.animateTo(1.0, duration: const Duration(seconds: 1), curve: Curves.linear), throwsAssertionError);
expect(() => controller.jumpTo(1.0), throwsAssertionError);
});
testWidgets('Write operations on ScrollControllers with more than one position do not throw', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
children: <Widget>[
Container(
constraints: const BoxConstraints(maxHeight: 500.0),
child: ListView(
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(height: 200.0, child: Text(state));
}).toList(),
),
),
Container(
constraints: const BoxConstraints(maxHeight: 500.0),
child: ListView(
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(height: 200.0, child: Text(state));
}).toList(),
),
),
],
),
),
);
controller.jumpTo(1.0);
controller.animateTo(1.0, duration: const Duration(seconds: 1), curve: Curves.linear);
await tester.pumpAndSettle();
});
testWidgets('Scroll controllers notify when the position changes', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
final List<double> log = <double>[];
controller.addListener(() {
log.add(controller.offset);
});
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
controller: controller,
children: kStates.map<Widget>((String state) {
return Container(height: 200.0, child: Text(state));
}).toList(),
),
),
);
expect(log, isEmpty);
await tester.drag(find.byType(ListView), const Offset(0.0, -250.0));
expect(log, equals(<double>[ 20.0, 250.0 ]));
log.clear();
controller.dispose();
await tester.drag(find.byType(ListView), const Offset(0.0, -130.0));
expect(log, isEmpty);
});
testWidgets('keepScrollOffset', (WidgetTester tester) async {
final PageStorageBucket bucket = PageStorageBucket();
Widget buildFrame(ScrollController controller) {
return Directionality(
textDirection: TextDirection.ltr,
child: PageStorage(
bucket: bucket,
child: KeyedSubtree(
key: const PageStorageKey<String>('ListView'),
child: ListView(
key: UniqueKey(), // it's a different ListView every time
controller: controller,
children: List<Widget>.generate(50, (int index) {
return Container(height: 100.0, child: Text('Item $index'));
}).toList(),
),
),
),
);
}
// keepScrollOffset: true (the default). The scroll offset is restored
// when the ListView is recreated with a new ScrollController.
// The initialScrollOffset is used in this case, because there's no saved
// scroll offset.
ScrollController controller = ScrollController(initialScrollOffset: 200.0);
await tester.pumpWidget(buildFrame(controller));
expect(tester.getTopLeft(find.widgetWithText(Container, 'Item 2')), Offset.zero);
controller.jumpTo(2000.0);
await tester.pump();
expect(tester.getTopLeft(find.widgetWithText(Container, 'Item 20')), Offset.zero);
// The initialScrollOffset isn't used in this case, because the scrolloffset
// can be restored.
controller = ScrollController(initialScrollOffset: 25.0);
await tester.pumpWidget(buildFrame(controller));
expect(controller.offset, 2000.0);
expect(tester.getTopLeft(find.widgetWithText(Container, 'Item 20')), Offset.zero);
// keepScrollOffset: false. The scroll offset is -not- restored
// when the ListView is recreated with a new ScrollController and
// the initialScrollOffset is used.
controller = ScrollController(keepScrollOffset: false, initialScrollOffset: 100.0);
await tester.pumpWidget(buildFrame(controller));
expect(controller.offset, 100.0);
expect(tester.getTopLeft(find.widgetWithText(Container, 'Item 1')), Offset.zero);
});
}