| // Copyright 2017 The Chromium 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/foundation.dart'; |
| import 'package:flutter/rendering.dart'; |
| import 'package:flutter/widgets.dart'; |
| |
| import '../rendering/mock_canvas.dart'; |
| import '../rendering/rendering_tester.dart'; |
| |
| void main() { |
| group('construction check', () { |
| testWidgets('ListWheelScrollView needs positive diameter ratio', (WidgetTester tester) async { |
| try { |
| new ListWheelScrollView( |
| diameterRatio: nonconst(-2.0), |
| itemExtent: 20.0, |
| children: const <Widget>[], |
| ); |
| fail('Expected failure with negative diameterRatio'); |
| } on AssertionError catch (exception) { |
| expect(exception.message, contains("You can't set a diameterRatio of 0")); |
| } |
| }); |
| |
| testWidgets('ListWheelScrollView needs positive item extent', (WidgetTester tester) async { |
| expect( |
| () { |
| new ListWheelScrollView( |
| itemExtent: null, |
| children: <Widget>[new Container()], |
| ); |
| }, |
| throwsAssertionError, |
| ); |
| }); |
| |
| testWidgets('ListWheelScrollView can have zero child', (WidgetTester tester) async { |
| await tester.pumpWidget( |
| const Directionality( |
| textDirection: TextDirection.ltr, |
| child: const ListWheelScrollView( |
| itemExtent: 50.0, |
| children: const <Widget>[], |
| ), |
| ), |
| ); |
| expect(tester.getSize(find.byType(ListWheelScrollView)), const Size(800.0, 600.0)); |
| }); |
| }); |
| |
| group('layout', () { |
| testWidgets("ListWheelScrollView takes parent's size with small children", (WidgetTester tester) async { |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| // Inner children smaller than the outer window. |
| itemExtent: 50.0, |
| children: <Widget>[ |
| new Container( |
| height: 50.0, |
| color: const Color(0xFFFFFFFF), |
| ), |
| ], |
| ), |
| ), |
| ); |
| expect(tester.getTopLeft(find.byType(ListWheelScrollView)), const Offset(0.0, 0.0)); |
| // Standard test screen size. |
| expect(tester.getBottomRight(find.byType(ListWheelScrollView)), const Offset(800.0, 600.0)); |
| }); |
| |
| testWidgets("ListWheelScrollView takes parent's size with large children", (WidgetTester tester) async { |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| // Inner children 5000.0px. |
| itemExtent: 50.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return new Container( |
| height: 50.0, |
| color: const Color(0xFFFFFFFF), |
| ); |
| }), |
| ), |
| ), |
| ); |
| expect(tester.getTopLeft(find.byType(ListWheelScrollView)), const Offset(0.0, 0.0)); |
| // Still fills standard test screen size. |
| expect(tester.getBottomRight(find.byType(ListWheelScrollView)), const Offset(800.0, 600.0)); |
| }); |
| |
| testWidgets("ListWheelScrollView children can't be bigger than itemExtent", (WidgetTester tester) async { |
| await tester.pumpWidget( |
| const Directionality( |
| textDirection: TextDirection.ltr, |
| child: const ListWheelScrollView( |
| itemExtent: 50.0, |
| children: const <Widget>[ |
| const SizedBox( |
| height: 200.0, |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| expect(tester.getSize(find.byType(SizedBox)), const Size(200.0, 50.0)); |
| expect(find.text('blah'), findsOneWidget); |
| }); |
| }); |
| |
| group('pre-transform viewport', () { |
| testWidgets('ListWheelScrollView starts and ends from the middle', (WidgetTester tester) async { |
| final ScrollController controller = new ScrollController(); |
| final List<int> paintedChildren = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return new CustomPaint( |
| painter: new TestCallbackPainter(onPaint: () { |
| paintedChildren.add(index); |
| }), |
| ); |
| }), |
| ), |
| ), |
| ); |
| |
| // Screen is 600px tall and the first item starts at 250px. The first 4 |
| // children are visible. |
| expect(paintedChildren, <int>[0, 1, 2, 3]); |
| |
| controller.jumpTo(1000.0); |
| paintedChildren.clear(); |
| |
| await tester.pump(); |
| // Item number 10 is now in the middle of the screen at 250px. 9, 8, 7 are |
| // visible before it and 11, 12, 13 are visible after it. |
| expect(paintedChildren, <int>[7, 8, 9, 10, 11, 12, 13]); |
| |
| // Move to the last item. |
| controller.jumpTo(9900.0); |
| paintedChildren.clear(); |
| |
| await tester.pump(); |
| // Item 99 is in the middle at 250px. |
| expect(paintedChildren, <int>[96, 97, 98, 99]); |
| }); |
| |
| testWidgets('A child gets painted as soon as its first pixel is in the viewport', (WidgetTester tester) async { |
| final ScrollController controller = new ScrollController(initialScrollOffset: 50.0); |
| final List<int> paintedChildren = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(10, (int index) { |
| return new CustomPaint( |
| painter: new TestCallbackPainter(onPaint: () { |
| paintedChildren.add(index); |
| }), |
| ); |
| }), |
| ), |
| ), |
| ); |
| |
| // Screen is 600px tall and the first item starts at 200px. The first 4 |
| // children are visible. |
| expect(paintedChildren, <int>[0, 1, 2, 3]); |
| |
| paintedChildren.clear(); |
| // Move down by 1px. |
| await tester.drag(find.byType(ListWheelScrollView), const Offset(0.0, -1.0)); |
| await tester.pump(); |
| |
| // Now the first pixel of item 5 enters the viewport. |
| expect(paintedChildren, <int>[0, 1, 2, 3, 4]); |
| }); |
| |
| testWidgets('A child is no longer painted after its last pixel leaves the viewport', (WidgetTester tester) async { |
| final ScrollController controller = new ScrollController(initialScrollOffset: 250.0); |
| final List<int> paintedChildren = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(10, (int index) { |
| return new CustomPaint( |
| painter: new TestCallbackPainter(onPaint: () { |
| paintedChildren.add(index); |
| }), |
| ); |
| }), |
| ), |
| ), |
| ); |
| |
| // The first item is at 0px and the 600px screen is full in the |
| // **untransformed plane's viewport painting coordinates** |
| expect(paintedChildren, <int>[0, 1, 2, 3, 4, 5]); |
| |
| paintedChildren.clear(); |
| // Go down another 99px. |
| controller.jumpTo(349.0); |
| await tester.pump(); |
| |
| // One more item now visible with the last pixel of 0 showing. |
| expect(paintedChildren, <int>[0, 1, 2, 3, 4, 5, 6]); |
| |
| paintedChildren.clear(); |
| // Go down one more pixel. |
| controller.jumpTo(350.0); |
| await tester.pump(); |
| |
| // Item 0 no longer visible. |
| expect(paintedChildren, <int>[1, 2, 3, 4, 5, 6]); |
| }); |
| }); |
| |
| group('viewport transformation', () { |
| testWidgets('Default middle transform', (WidgetTester tester) async { |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| final RenderListWheelViewport viewport = tester.firstRenderObject(find.byType(Container)).parent; |
| expect(viewport, paints..transform( |
| matrix4: equals(<dynamic>[ |
| 1.0, 0.0, 0.0, 0.0, |
| 0.0, 1.0, 0.0, 0.0, |
| -1.2 /* origin centering multiplied */, -0.9/* origin centering multiplied*/, 1.0, -0.003 /* inverse of perspective */, |
| moreOrLessEquals(0.0), moreOrLessEquals(0.0), 0.0, moreOrLessEquals(1.0), |
| ]), |
| )); |
| }); |
| |
| testWidgets('Scrolling, diameterRatio, perspective all changes matrix', (WidgetTester tester) async { |
| final ScrollController controller = new ScrollController(initialScrollOffset: 200.0); |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| final RenderListWheelViewport viewport = tester.firstRenderObject(find.byType(Container)).parent; |
| expect(viewport, paints..transform( |
| matrix4: equals(<dynamic>[ |
| 1.0, 0.0, 0.0, 0.0, |
| moreOrLessEquals(-0.41042417199080244), moreOrLessEquals(0.6318744917928065), moreOrLessEquals(0.3420201433256687), moreOrLessEquals(-0.0010260604299770061), |
| moreOrLessEquals(-1.12763114494309), moreOrLessEquals(-1.1877435020329863), moreOrLessEquals(0.9396926207859084), moreOrLessEquals(-0.0028190778623577253), |
| moreOrLessEquals(166.54856463138663), moreOrLessEquals(-62.20844875763376), moreOrLessEquals(-138.79047052615562), moreOrLessEquals(1.4163714115784667), |
| ]), |
| )); |
| |
| // Increase diameter. |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| diameterRatio: 3.0, |
| itemExtent: 100.0, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| expect(viewport, paints..transform( |
| matrix4: equals(<dynamic>[ |
| 1.0, 0.0, 0.0, 0.0, |
| moreOrLessEquals(-0.26954971336161726), moreOrLessEquals(0.7722830529455648), moreOrLessEquals(0.22462476113468105), moreOrLessEquals(-0.0006738742834040432), |
| moreOrLessEquals(-1.1693344055601331), moreOrLessEquals(-1.101625565304781), moreOrLessEquals(0.9744453379667777), moreOrLessEquals(-0.002923336013900333), |
| moreOrLessEquals(108.46394900436536), moreOrLessEquals(-113.14792465797223), moreOrLessEquals(-90.38662417030434), moreOrLessEquals(1.2711598725109134), |
| ]), |
| )); |
| |
| // Decrease perspective. |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| perspective: 0.0001, |
| itemExtent: 100.0, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| expect(viewport, paints..transform( |
| matrix4: equals(<dynamic>[ |
| 1.0, 0.0, 0.0, 0.0, |
| moreOrLessEquals(-0.01368080573302675), moreOrLessEquals(0.9294320164861384), moreOrLessEquals(0.3420201433256687), moreOrLessEquals(-0.000034202014332566874), |
| moreOrLessEquals(-0.03758770483143634), moreOrLessEquals(-0.370210921949246), moreOrLessEquals(0.9396926207859084), moreOrLessEquals(-0.00009396926207859085), |
| moreOrLessEquals(5.551618821046304), moreOrLessEquals(-182.95615811538906), moreOrLessEquals(-138.79047052615562), moreOrLessEquals(1.0138790470526158), |
| ]), |
| )); |
| |
| // Scroll a bit. |
| controller.jumpTo(300.0); |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| expect(viewport, paints..transform( |
| matrix4: equals(<dynamic>[ |
| 1.0, 0.0, 0.0, 0.0, |
| -0.6, moreOrLessEquals(0.41602540378443875), moreOrLessEquals(0.5), moreOrLessEquals(-0.0015), |
| moreOrLessEquals(-1.0392304845413265), moreOrLessEquals(-1.2794228634059948), moreOrLessEquals(0.8660254037844387), moreOrLessEquals(-0.0025980762113533163), |
| moreOrLessEquals(276.46170927520404), moreOrLessEquals(-52.46133917892857), moreOrLessEquals(-230.38475772933677), moreOrLessEquals(1.69115427318801), |
| ]), |
| )); |
| }); |
| |
| testWidgets('Painting creates layers', (WidgetTester tester) async { |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| expect( |
| new List<TransformLayer>.from( |
| tester.layers.where((Layer layer) => layer is TransformLayer) |
| ) |
| .map((TransformLayer layer) => layer.transform.storage) |
| .toList(), |
| contains(equals(<dynamic>[ |
| 1.0, 0.0, 0.0, 0.0, |
| 0.0, 1.0, 0.0, 0.0, |
| -1.2, -0.9, 1.0, -0.003, |
| moreOrLessEquals(0.0), moreOrLessEquals(0.0), 0.0, moreOrLessEquals(1.0), |
| ])), |
| ); |
| }); |
| }); |
| |
| group('scroll notifications', () { |
| testWidgets('no onSelectedItemChanged callback on first build', (WidgetTester tester) async { |
| bool itemChangeCalled = false; |
| final ValueChanged<int> onItemChange = (_) { itemChangeCalled = true; }; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| onSelectedItemChanged: onItemChange, |
| children: <Widget>[ |
| new Container( |
| width: 200.0, |
| child: const Center( |
| child: const Text('blah'), |
| ), |
| ), |
| ], |
| ), |
| ), |
| ); |
| |
| expect(itemChangeCalled, false); |
| }); |
| |
| testWidgets('onSelectedItemChanged when a new item is closest to center', (WidgetTester tester) async { |
| final List<int> selectedItems = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| onSelectedItemChanged: (int index) { selectedItems.add(index); }, |
| children: new List<Widget>.generate(10, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ); |
| |
| final TestGesture scrollGesture = await tester.startGesture(const Offset(10.0, 10.0)); |
| // Item 0 is still closest to the center. No updates. |
| await scrollGesture.moveBy(const Offset(0.0, -49.0)); |
| expect(selectedItems.isEmpty, true); |
| |
| // Now item 1 is closest to the center. |
| await scrollGesture.moveBy(const Offset(0.0, -1.0)); |
| expect(selectedItems, <int>[1]); |
| |
| // Now item 1 is still closest to the center for another full itemExtent (100px). |
| await scrollGesture.moveBy(const Offset(0.0, -99.0)); |
| expect(selectedItems, <int>[1]); |
| |
| await scrollGesture.moveBy(const Offset(0.0, -1.0)); |
| expect(selectedItems, <int>[1, 2]); |
| |
| // Going back triggers previous item indices. |
| await scrollGesture.moveBy(const Offset(0.0, 50.0)); |
| expect(selectedItems, <int>[1, 2, 1]); |
| }); |
| |
| testWidgets('onSelectedItemChanged reports only in valid range', (WidgetTester tester) async { |
| final List<int> selectedItems = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| onSelectedItemChanged: (int index) { selectedItems.add(index); }, |
| // So item 0 is at 0 and item 9 is at 900 in the scrollable range. |
| children: new List<Widget>.generate(10, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ); |
| |
| final TestGesture scrollGesture = await tester.startGesture(const Offset(10.0, 10.0)); |
| |
| // First move back past the beginning. |
| await scrollGesture.moveBy(const Offset(0.0, 70.0)); |
| |
| for (double verticalOffset = 0.0; verticalOffset > -2000.0; verticalOffset -= 10.0) { |
| // Then gradually move down by a total vertical extent much higher than |
| // the scrollable extent. |
| await scrollGesture.moveTo(new Offset(0.0, verticalOffset)); |
| } |
| |
| // The list should only cover the list of valid items. Item 0 would not |
| // be included because the current item never left the 0 index until it |
| // went to 1. |
| expect(selectedItems, <int>[1, 2, 3, 4, 5, 6, 7, 8, 9]); |
| }); |
| }); |
| |
| group('scroll controller', () { |
| testWidgets('initialItem', (WidgetTester tester) async { |
| final FixedExtentScrollController controller = new FixedExtentScrollController(initialItem: 10); |
| final List<int> paintedChildren = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return new CustomPaint( |
| painter: new TestCallbackPainter(onPaint: () { |
| paintedChildren.add(index); |
| }), |
| ); |
| }), |
| ), |
| ), |
| ); |
| |
| // Screen is 600px tall. Item 10 is in the center and each item is 100px tall. |
| expect(paintedChildren, <int>[7, 8, 9, 10, 11, 12, 13]); |
| expect(controller.selectedItem, 10); |
| }); |
| |
| testWidgets('controller jump', (WidgetTester tester) async { |
| final FixedExtentScrollController controller = new FixedExtentScrollController(initialItem: 10); |
| final List<int> paintedChildren = <int>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return new CustomPaint( |
| painter: new TestCallbackPainter(onPaint: () { |
| paintedChildren.add(index); |
| }), |
| ); |
| }), |
| ), |
| ), |
| ); |
| |
| // Screen is 600px tall. Item 10 is in the center and each item is 100px tall. |
| expect(paintedChildren, <int>[7, 8, 9, 10, 11, 12, 13]); |
| |
| paintedChildren.clear(); |
| controller.jumpToItem(0); |
| await tester.pump(); |
| |
| expect(paintedChildren, <int>[0, 1, 2, 3]); |
| expect(controller.selectedItem, 0); |
| }); |
| |
| testWidgets('onSelectedItemChanged and controller are in sync', (WidgetTester tester) async { |
| final List<int> selectedItems = <int>[]; |
| final FixedExtentScrollController controller = new FixedExtentScrollController(initialItem: 10); |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: controller, |
| itemExtent: 100.0, |
| onSelectedItemChanged: (int index) { selectedItems.add(index); }, |
| children: new List<Widget>.generate(100, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ); |
| |
| final TestGesture scrollGesture = await tester.startGesture(const Offset(10.0, 10.0)); |
| await scrollGesture.moveBy(const Offset(0.0, -49.0)); |
| await tester.pump(); |
| expect(selectedItems.isEmpty, true); |
| expect(controller.selectedItem, 10); |
| |
| await scrollGesture.moveBy(const Offset(0.0, -1.0)); |
| await tester.pump(); |
| expect(selectedItems, <int>[11]); |
| expect(controller.selectedItem, 11); |
| |
| await scrollGesture.moveBy(const Offset(0.0, 70.0)); |
| await tester.pump(); |
| expect(selectedItems, <int>[11, 10]); |
| expect(controller.selectedItem, 10); |
| }); |
| |
| testWidgets('controller hot swappable', (WidgetTester tester) async { |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ); |
| |
| // Item 5 is now selected. |
| await tester.drag(find.byType(ListWheelScrollView), const Offset(0.0, -500.0)); |
| await tester.pump(); |
| |
| final FixedExtentScrollController newController = |
| new FixedExtentScrollController(initialItem: 30); |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| controller: newController, |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ); |
| |
| // initialItem doesn't do anything since the scroll position was already |
| // created. |
| expect(newController.selectedItem, 5); |
| |
| newController.jumpToItem(50); |
| expect(newController.selectedItem, 50); |
| expect(newController.position.pixels, 5000.0); |
| |
| // Now remove the controller |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new ListWheelScrollView( |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ); |
| |
| // Internally, that same controller is still attached and still at the |
| // same place. |
| expect(newController.selectedItem, 50); |
| }); |
| }); |
| |
| group('physics', () { |
| testWidgets('fling velocities too low snaps back to the same item', (WidgetTester tester) async { |
| final FixedExtentScrollController controller = new FixedExtentScrollController(initialItem: 40); |
| final List<double> scrolledPositions = <double>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new NotificationListener<ScrollNotification>( |
| onNotification: (ScrollNotification notification) { |
| if (notification is ScrollUpdateNotification) { |
| scrolledPositions.add(notification.metrics.pixels); |
| } |
| }, |
| child: new ListWheelScrollView( |
| controller: controller, |
| physics: const FixedExtentScrollPhysics(), |
| itemExtent: 1000.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ), |
| ); |
| |
| await tester.fling( |
| find.byType(ListWheelScrollView), |
| const Offset(0.0, -50.0), |
| 800.0, |
| ); |
| |
| // At this moment, the ballistics is started but 50px is still inside the |
| // initial item. |
| expect(controller.selectedItem, 40); |
| // A tester.fling creates and pumps 50 pointer events. |
| expect(scrolledPositions.length, 50); |
| expect(scrolledPositions.last, moreOrLessEquals(40 * 1000.0 + 50.0, epsilon: 0.2)); |
| |
| // Let the spring back simulation finish. |
| await tester.pump(); |
| await tester.pump(const Duration(seconds: 1)); |
| |
| // The simulation actually did stuff after start ballistics. |
| expect(scrolledPositions.length, greaterThan(50)); |
| // Though it still lands back to the same item with the same scroll offset. |
| expect(controller.selectedItem, 40); |
| expect(scrolledPositions.last, moreOrLessEquals(40 * 1000.0, epsilon: 0.2)); |
| }); |
| |
| testWidgets('high fling velocities lands exactly on items', (WidgetTester tester) async { |
| debugDefaultTargetPlatformOverride = TargetPlatform.iOS; |
| |
| final FixedExtentScrollController controller = new FixedExtentScrollController(initialItem: 40); |
| final List<double> scrolledPositions = <double>[]; |
| |
| await tester.pumpWidget( |
| new Directionality( |
| textDirection: TextDirection.ltr, |
| child: new NotificationListener<ScrollNotification>( |
| onNotification: (ScrollNotification notification) { |
| if (notification is ScrollUpdateNotification) { |
| scrolledPositions.add(notification.metrics.pixels); |
| } |
| }, |
| child: new ListWheelScrollView( |
| controller: controller, |
| physics: const FixedExtentScrollPhysics(), |
| itemExtent: 100.0, |
| children: new List<Widget>.generate(100, (int index) { |
| return const Placeholder(); |
| }), |
| ), |
| ), |
| ), |
| ); |
| |
| await tester.fling( |
| find.byType(ListWheelScrollView), |
| // High and random numbers that's unlikely to land on exact multiples of 100. |
| const Offset(0.0, -567.0), |
| 678.0, |
| ); |
| |
| // After the drag, 40 + 567px should be on the 46th item. |
| expect(controller.selectedItem, 46); |
| // A tester.fling creates and pumps 50 pointer events. |
| expect(scrolledPositions.length, 50); |
| expect(scrolledPositions.last, moreOrLessEquals(40 * 100.0 + 567.0, epsilon: 0.2)); |
| |
| // Let the spring back simulation finish. |
| await tester.pumpAndSettle(); |
| |
| // The simulation actually did stuff after start ballistics. |
| expect(scrolledPositions.length, greaterThan(50)); |
| // Lands on 49. |
| expect(controller.selectedItem, 49); |
| // More importantly, lands tightly on 49. |
| expect(scrolledPositions.last, moreOrLessEquals(49 * 100.0, epsilon: 0.2)); |
| |
| debugDefaultTargetPlatformOverride = null; |
| }); |
| }); |
| } |
