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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.
// @dart = 2.8
import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/widgets.dart';
const List<int> items = <int>[0, 1, 2, 3, 4, 5];
Widget buildFrame() {
return Directionality(
textDirection: TextDirection.ltr,
child: ListView(
itemExtent: 290.0,
scrollDirection: Axis.vertical,
children: items.map<Widget>((int item) {
return Container(
child: Text('$item'),
);
}).toList(),
),
);
}
void main() {
testWidgets('Drag vertically', (WidgetTester tester) async {
await tester.pumpWidget(buildFrame());
await tester.pump();
await tester.drag(find.text('1'), const Offset(0.0, -300.0));
await tester.pump();
// screen is 600px high, and has the following items:
// -10..280 = 1
// 280..570 = 2
// 570..860 = 3
expect(find.text('0'), findsNothing);
expect(find.text('1'), findsOneWidget);
expect(find.text('2'), findsOneWidget);
expect(find.text('3'), findsOneWidget);
expect(find.text('4'), findsNothing);
expect(find.text('5'), findsNothing);
await tester.pump();
await tester.drag(find.text('2'), const Offset(0.0, -290.0));
await tester.pump();
// screen is 600px high, and has the following items:
// -10..280 = 2
// 280..570 = 3
// 570..860 = 4
expect(find.text('0'), findsNothing);
expect(find.text('1'), findsNothing);
expect(find.text('2'), findsOneWidget);
expect(find.text('3'), findsOneWidget);
expect(find.text('4'), findsOneWidget);
expect(find.text('5'), findsNothing);
await tester.pump();
await tester.drag(find.text('3'), const Offset(-300.0, 0.0));
await tester.pump();
// nothing should have changed
expect(find.text('0'), findsNothing);
expect(find.text('1'), findsNothing);
expect(find.text('2'), findsOneWidget);
expect(find.text('3'), findsOneWidget);
expect(find.text('4'), findsOneWidget);
expect(find.text('5'), findsNothing);
});
testWidgets('Drag vertically', (WidgetTester tester) async {
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: ListView(
itemExtent: 290.0,
padding: const EdgeInsets.only(top: 250.0),
scrollDirection: Axis.vertical,
children: items.map<Widget>((int item) {
return Container(
child: Text('$item'),
);
}).toList(),
),
),
);
await tester.pump();
// screen is 600px high, and has the following items:
// 250..540 = 0
// 540..830 = 1
expect(find.text('0'), findsOneWidget);
expect(find.text('1'), findsOneWidget);
expect(find.text('2'), findsNothing);
expect(find.text('3'), findsNothing);
expect(find.text('4'), findsNothing);
expect(find.text('5'), findsNothing);
await tester.drag(find.text('0'), const Offset(0.0, -300.0));
await tester.pump();
// screen is 600px high, and has the following items:
// -50..240 = 0
// 240..530 = 1
// 530..820 = 2
expect(find.text('0'), findsOneWidget);
expect(find.text('1'), findsOneWidget);
expect(find.text('2'), findsOneWidget);
expect(find.text('3'), findsNothing);
expect(find.text('4'), findsNothing);
expect(find.text('5'), findsNothing);
});
}