DEV/flutter_flutter
1
0
Fork 0
mirror of https://github.com/flutter/flutter.git synced 2026-02-20 02:29:02 +08:00
Code Issues Packages Projects Releases Wiki Activity

Fix selection area causes small scrollables to bounce (#112816)

Browse Source
This commit is contained in:
chunhtai 2022-10-10 12:57:02 -07:00 committed by GitHub
parent d03f631423
commit 492bfddd9f
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 82 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
packages/flutter/lib/src/widgets/scrollable.dart
View File

@ -989,6 +989,11 @@ class EdgeDraggingAutoScroller {
scrollRenderBox.getTransformTo(null),
Rect.fromLTWH(0, 0, scrollRenderBox.size.width, scrollRenderBox.size.height)
);
assert(
globalRect.size.width >= _dragTargetRelatedToScrollOrigin.size.width &&
globalRect.size.height >= _dragTargetRelatedToScrollOrigin.size.height,
'Drag target size is larger than scrollable size, which may cause bouncing',
);
_scrolling = true;
double? newOffset;
const double overDragMax = 20.0;
@ -1000,23 +1005,27 @@ class EdgeDraggingAutoScroller {
final double proxyStart = _offsetExtent(_dragTargetRelatedToScrollOrigin.topLeft, _scrollDirection);
final double proxyEnd = _offsetExtent(_dragTargetRelatedToScrollOrigin.bottomRight, _scrollDirection);
late double overDrag;
if (_axisDirection == AxisDirection.up || _axisDirection == AxisDirection.left) {
if (proxyEnd > viewportEnd && scrollable.position.pixels > scrollable.position.minScrollExtent) {
overDrag = math.max(proxyEnd - viewportEnd, overDragMax);
newOffset = math.max(scrollable.position.minScrollExtent, scrollable.position.pixels - overDrag);
} else if (proxyStart < viewportStart && scrollable.position.pixels < scrollable.position.maxScrollExtent) {
overDrag = math.max(viewportStart - proxyStart, overDragMax);
newOffset = math.min(scrollable.position.maxScrollExtent, scrollable.position.pixels + overDrag);
}
} else {
if (proxyStart < viewportStart && scrollable.position.pixels > scrollable.position.minScrollExtent) {
overDrag = math.max(viewportStart - proxyStart, overDragMax);
newOffset = math.max(scrollable.position.minScrollExtent, scrollable.position.pixels - overDrag);
} else if (proxyEnd > viewportEnd && scrollable.position.pixels < scrollable.position.maxScrollExtent) {
overDrag = math.max(proxyEnd - viewportEnd, overDragMax);
newOffset = math.min(scrollable.position.maxScrollExtent, scrollable.position.pixels + overDrag);
}
switch (_axisDirection) {
case AxisDirection.up:
case AxisDirection.left:
if (proxyEnd > viewportEnd && scrollable.position.pixels > scrollable.position.minScrollExtent) {
final double overDrag = math.min(proxyEnd - viewportEnd, overDragMax);
newOffset = math.max(scrollable.position.minScrollExtent, scrollable.position.pixels - overDrag);
} else if (proxyStart < viewportStart && scrollable.position.pixels < scrollable.position.maxScrollExtent) {
final double overDrag = math.min(viewportStart - proxyStart, overDragMax);
newOffset = math.min(scrollable.position.maxScrollExtent, scrollable.position.pixels + overDrag);
}
break;
case AxisDirection.right:
case AxisDirection.down:
if (proxyStart < viewportStart && scrollable.position.pixels > scrollable.position.minScrollExtent) {
final double overDrag = math.min(viewportStart - proxyStart, overDragMax);
newOffset = math.max(scrollable.position.minScrollExtent, scrollable.position.pixels - overDrag);
} else if (proxyEnd > viewportEnd && scrollable.position.pixels < scrollable.position.maxScrollExtent) {
final double overDrag = math.min(proxyEnd - viewportEnd, overDragMax);
newOffset = math.min(scrollable.position.maxScrollExtent, scrollable.position.pixels + overDrag);
}
break;
}
if (newOffset == null || (newOffset - scrollable.position.pixels).abs() < 1.0) {
@ -1055,7 +1064,10 @@ class _ScrollableSelectionContainerDelegate extends MultiSelectableSelectionCont
_position.addListener(_scheduleLayoutChange);
}
static const double _kDefaultDragTargetSize = 200;
// Pointer drag is a single point, it should not have a size.
static const double _kDefaultDragTargetSize = 0;
// An eye-balled value for a smooth scrolling speed.
static const double _kDefaultSelectToScrollVelocityScalar = 30;
final ScrollableState state;

58
packages/flutter/test/widgets/scrollable_selection_test.dart
View File

@ -125,7 +125,8 @@ void main() {
expect(controller.offset, 0.0);
double previousOffset = controller.offset;
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)));
// Scrollable only auto scroll if the drag passes the boundary.
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)) + const Offset(0, 20));
await tester.pump();
await tester.pump(const Duration(seconds: 1));
expect(controller.offset > previousOffset, isTrue);
@ -150,6 +151,50 @@ void main() {
await gesture.up();
});
testWidgets('select to scroll works for small scrollable', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
await tester.pumpWidget(MaterialApp(
home: SelectionArea(
selectionControls: materialTextSelectionControls,
child: Scaffold(
body: SizedBox(
height: 10,
child: ListView.builder(
controller: controller,
itemCount: 100,
itemBuilder: (BuildContext context, int index) {
return Text('Item $index');
},
),
),
),
),
));
final RenderParagraph paragraph1 = tester.renderObject<RenderParagraph>(find.descendant(of: find.text('Item 0'), matching: find.byType(RichText)));
final TestGesture gesture = await tester.startGesture(textOffsetToPosition(paragraph1, 2), kind: ui.PointerDeviceKind.mouse);
addTearDown(gesture.removePointer);
await tester.pump();
expect(controller.offset, 0.0);
double previousOffset = controller.offset;
// Scrollable only auto scroll if the drag passes the boundary
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)) + const Offset(0, 20));
await tester.pump();
await tester.pump(const Duration(milliseconds: 100));
expect(controller.offset > previousOffset, isTrue);
previousOffset = controller.offset;
await tester.pump();
await tester.pump(const Duration(milliseconds: 100));
expect(controller.offset > previousOffset, isTrue);
await gesture.up();
// Shouldn't be stuck if gesture is up.
await tester.pumpAndSettle(const Duration(seconds: 1));
expect(tester.takeException(), isNull);
});
testWidgets('select to scroll backward', (WidgetTester tester) async {
final ScrollController controller = ScrollController();
await tester.pumpWidget(MaterialApp(
@ -174,7 +219,7 @@ void main() {
expect(controller.offset, 4000);
double previousOffset = controller.offset;
await gesture.moveTo(tester.getTopLeft(find.byType(ListView)));
await gesture.moveTo(tester.getTopLeft(find.byType(ListView)) + const Offset(0, -20));
await tester.pump();
await tester.pump(const Duration(seconds: 1));
expect(controller.offset < previousOffset, isTrue);
@ -220,7 +265,8 @@ void main() {
expect(controller.offset, 0.0);
double previousOffset = controller.offset;
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)));
// Scrollable only auto scroll if the drag passes the boundary
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)) + const Offset(20, 0));
await tester.pump();
await tester.pump(const Duration(seconds: 1));
expect(controller.offset > previousOffset, isTrue);
@ -268,7 +314,7 @@ void main() {
expect(controller.offset, 2080);
double previousOffset = controller.offset;
await gesture.moveTo(tester.getTopLeft(find.byType(ListView)));
await gesture.moveTo(tester.getTopLeft(find.byType(ListView)) + const Offset(-10, 0));
await tester.pump();
await tester.pump(const Duration(seconds: 1));
expect(controller.offset < previousOffset, isTrue);
@ -427,8 +473,8 @@ void main() {
expect(controller.offset, 0.0);
double previousOffset = controller.offset;
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)));
// Scrollable only auto scroll if the drag passes the boundary
await gesture.moveTo(tester.getBottomRight(find.byType(ListView)) + const Offset(0, 40));
await tester.pump();
await tester.pump(const Duration(seconds: 1));
expect(controller.offset > previousOffset, isTrue);