// 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/material.dart'; import '../rendering/mock_canvas.dart'; Widget _buildSingleChildScrollViewWithScrollbar({ TextDirection textDirection = TextDirection.ltr, EdgeInsets padding = EdgeInsets.zero, Widget? child, }) { return Directionality( textDirection: textDirection, child: MediaQuery( data: MediaQueryData(padding: padding), child: Scrollbar( child: SingleChildScrollView(child: child), ), ), ); } void main() { testWidgets('Viewport basic test (LTR)', (WidgetTester tester) async { await tester.pumpWidget(_buildSingleChildScrollViewWithScrollbar( child: const SizedBox(width: 4000.0, height: 4000.0), )); expect(find.byType(Scrollbar), isNot(paints..rect())); await tester.fling(find.byType(SingleChildScrollView), const Offset(0.0, -10.0), 10.0); expect(find.byType(Scrollbar), paints..rect(rect: const Rect.fromLTRB(800.0 - 6.0, 1.5, 800.0, 91.5))); }); testWidgets('Viewport basic test (RTL)', (WidgetTester tester) async { await tester.pumpWidget(_buildSingleChildScrollViewWithScrollbar( textDirection: TextDirection.rtl, child: const SizedBox(width: 4000.0, height: 4000.0), )); expect(find.byType(Scrollbar), isNot(paints..rect())); await tester.fling(find.byType(SingleChildScrollView), const Offset(0.0, -10.0), 10.0); expect(find.byType(Scrollbar), paints..rect(rect: const Rect.fromLTRB(0.0, 1.5, 6.0, 91.5))); }); testWidgets('works with MaterialApp and Scaffold', (WidgetTester tester) async { await tester.pumpWidget(MaterialApp( home: MediaQuery( data: const MediaQueryData( padding: EdgeInsets.fromLTRB(0, 20, 0, 34) ), child: Scaffold( appBar: AppBar(title: const Text('Title')), body: Scrollbar( child: ListView( children: const <Widget>[SizedBox(width: 4000, height: 4000)] ), ), ), ), )); final TestGesture gesture = await tester.startGesture(tester.getCenter(find.byType(ListView))); // On Android it should not overscroll. await gesture.moveBy(const Offset(0, 100)); // Trigger fade in animation. await tester.pump(); await tester.pump(const Duration(milliseconds: 500)); expect(find.byType(Scrollbar), paints..rect( rect: const Rect.fromLTWH( 800.0 - 6, // screen width - thickness 0, // the paint area starts from the bottom of the app bar 6, // thickness // 56 being the height of the app bar (600.0 - 56 - 34 - 20) / 4000 * (600 - 56 - 34 - 20), ), )); }); testWidgets("should not paint when there isn't enough space", (WidgetTester tester) async { await tester.pumpWidget(MaterialApp( home: MediaQuery( data: const MediaQueryData( padding: EdgeInsets.fromLTRB(0, 20, 0, 34) ), child: Scaffold( appBar: AppBar(title: const Text('Title')), body: Scrollbar( child: ListView( children: const <Widget>[SizedBox(width: 40, height: 40)] ), ), ), ), )); final TestGesture gesture = await tester.startGesture(tester.getCenter(find.byType(ListView))); // On Android it should not overscroll. await gesture.moveBy(const Offset(0, 100)); // Trigger fade in animation. await tester.pump(); await tester.pump(const Duration(milliseconds: 500)); expect(find.byType(Scrollbar), isNot(paints..rect())); }); }