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Revert "Add SliverGrid and ScrollGrid" (#7769)

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This commit is contained in:
Ian Hickson 2017-01-31 17:34:02 -08:00 committed by GitHub
parent a0f0c42fe3
commit 32784d35f9
16 changed files with 186 additions and 1117 deletions
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76
examples/flutter_gallery/lib/demo/grid_list_demo.dart
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@ -131,9 +131,9 @@ class _GridPhotoViewerState extends State<GridPhotoViewer> with SingleTickerProv
..translate(_offset.dx, _offset.dy) ..translate(_offset.dx, _offset.dy)
..scale(_scale), ..scale(_scale),
child: new ClipRect( child: new ClipRect(
child: new Image.asset(config.photo.assetName, fit: ImageFit.cover), child: new Image.asset(config.photo.assetName, fit: ImageFit.cover)
), )
), )
); );
} }
); );
@ -200,11 +200,11 @@ class GridDemoPhotoItem extends StatelessWidget {
backgroundColor: Colors.black45, backgroundColor: Colors.black45,
leading: new Icon( leading: new Icon(
icon, icon,
color: Colors.white, color: Colors.white
), )
), )
), ),
child: image, child: image
); );
case GridDemoTileStyle.twoLine: case GridDemoTileStyle.twoLine:
@ -217,11 +217,11 @@ class GridDemoPhotoItem extends StatelessWidget {
subtitle: new _GridTitleText(photo.caption), subtitle: new _GridTitleText(photo.caption),
trailing: new Icon( trailing: new Icon(
icon, icon,
color: Colors.white, color: Colors.white
), )
), )
), ),
child: image, child: image
); );
} }
assert(tileStyle != null); assert(tileStyle != null);
@ -245,62 +245,62 @@ class GridListDemoState extends State<GridListDemo> {
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_0.jpg', assetName: 'packages/flutter_gallery_assets/landscape_0.jpg',
title: 'Philippines', title: 'Philippines',
caption: 'Batad rice terraces', caption: 'Batad rice terraces'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_1.jpg', assetName: 'packages/flutter_gallery_assets/landscape_1.jpg',
title: 'Italy', title: 'Italy',
caption: 'Ceresole Reale', caption: 'Ceresole Reale'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_2.jpg', assetName: 'packages/flutter_gallery_assets/landscape_2.jpg',
title: 'Somewhere', title: 'Somewhere',
caption: 'Beautiful mountains', caption: 'Beautiful mountains'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_3.jpg', assetName: 'packages/flutter_gallery_assets/landscape_3.jpg',
title: 'A place', title: 'A place',
caption: 'Beautiful hills', caption: 'Beautiful hills'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_4.jpg', assetName: 'packages/flutter_gallery_assets/landscape_4.jpg',
title: 'New Zealand', title: 'New Zealand',
caption: 'View from the van', caption: 'View from the van'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_5.jpg', assetName: 'packages/flutter_gallery_assets/landscape_5.jpg',
title: 'Autumn', title: 'Autumn',
caption: 'The golden season', caption: 'The golden season'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_6.jpg', assetName: 'packages/flutter_gallery_assets/landscape_6.jpg',
title: 'Germany', title: 'Germany',
caption: 'Englischer Garten', caption: 'Englischer Garten'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_7.jpg', assetName: 'packages/flutter_gallery_assets/landscape_7.jpg',
title: 'A country', title: 'A country',
caption: 'Grass fields', caption: 'Grass fields'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_8.jpg', assetName: 'packages/flutter_gallery_assets/landscape_8.jpg',
title: 'Mountain country', title: 'Mountain country',
caption: 'River forest', caption: 'River forest'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_9.jpg', assetName: 'packages/flutter_gallery_assets/landscape_9.jpg',
title: 'Alpine place', title: 'Alpine place',
caption: 'Green hills', caption: 'Green hills'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_10.jpg', assetName: 'packages/flutter_gallery_assets/landscape_10.jpg',
title: 'Desert land', title: 'Desert land',
caption: 'Blue skies', caption: 'Blue skies'
), ),
new Photo( new Photo(
assetName: 'packages/flutter_gallery_assets/landscape_11.jpg', assetName: 'packages/flutter_gallery_assets/landscape_11.jpg',
title: 'Narnia', title: 'Narnia',
caption: 'Rocks and rivers', caption: 'Rocks and rivers'
), ),
]; ];
@ -325,29 +325,31 @@ class GridListDemoState extends State<GridListDemo> {
itemBuilder: (BuildContext context) => <PopupMenuItem<GridDemoTileStyle>>[ itemBuilder: (BuildContext context) => <PopupMenuItem<GridDemoTileStyle>>[
new PopupMenuItem<GridDemoTileStyle>( new PopupMenuItem<GridDemoTileStyle>(
value: GridDemoTileStyle.imageOnly, value: GridDemoTileStyle.imageOnly,
child: new Text('Image only'), child: new Text('Image only')
), ),
new PopupMenuItem<GridDemoTileStyle>( new PopupMenuItem<GridDemoTileStyle>(
value: GridDemoTileStyle.oneLine, value: GridDemoTileStyle.oneLine,
child: new Text('One line'), child: new Text('One line')
), ),
new PopupMenuItem<GridDemoTileStyle>( new PopupMenuItem<GridDemoTileStyle>(
value: GridDemoTileStyle.twoLine, value: GridDemoTileStyle.twoLine,
child: new Text('Two line'), child: new Text('Two line')
), )
], ]
), )
], ]
), ),
body: new Column( body: new Column(
children: <Widget>[ children: <Widget>[
new Expanded( new Expanded(
child: new ScrollGrid.count( child: new ScrollableGrid(
crossAxisCount: (orientation == Orientation.portrait) ? 2 : 3, delegate: new FixedColumnCountGridDelegate(
mainAxisSpacing: 4.0, columnCount: (orientation == Orientation.portrait) ? 2 : 3,
crossAxisSpacing: 4.0, rowSpacing: 4.0,
padding: const EdgeInsets.all(4.0), columnSpacing: 4.0,
childAspectRatio: (orientation == Orientation.portrait) ? 1.0 : 1.3, padding: const EdgeInsets.all(4.0),
tileAspectRatio: (orientation == Orientation.portrait) ? 1.0 : 1.3
),
children: photos.map((Photo photo) { children: photos.map((Photo photo) {
return new GridDemoPhotoItem( return new GridDemoPhotoItem(
photo: photo, photo: photo,
@ -358,7 +360,7 @@ class GridListDemoState extends State<GridListDemo> {
}); });
} }
); );
}).toList(), })
) )
) )
] ]

1
packages/flutter/lib/rendering.dart
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@ -47,7 +47,6 @@ export 'src/rendering/shifted_box.dart';
export 'src/rendering/sliver.dart'; export 'src/rendering/sliver.dart';
export 'src/rendering/sliver_app_bar.dart'; export 'src/rendering/sliver_app_bar.dart';
export 'src/rendering/sliver_block.dart'; export 'src/rendering/sliver_block.dart';
export 'src/rendering/sliver_grid.dart';
export 'src/rendering/sliver_list.dart'; export 'src/rendering/sliver_list.dart';
export 'src/rendering/sliver_multi_box_adaptor.dart'; export 'src/rendering/sliver_multi_box_adaptor.dart';
export 'src/rendering/sliver_padding.dart'; export 'src/rendering/sliver_padding.dart';

30
packages/flutter/lib/src/rendering/sliver.dart
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@ -282,9 +282,7 @@ class SliverConstraints extends Constraints {
BoxConstraints asBoxConstraints({ BoxConstraints asBoxConstraints({
double minExtent: 0.0, double minExtent: 0.0,
double maxExtent: double.INFINITY, double maxExtent: double.INFINITY,
double crossAxisExtent,
}) { }) {
crossAxisExtent ??= this.crossAxisExtent;
switch (axis) { switch (axis) {
case Axis.horizontal: case Axis.horizontal:
return new BoxConstraints( return new BoxConstraints(
@ -817,16 +815,13 @@ abstract class RenderSliver extends RenderObject {
/// the [RenderSliverHelpers] mixin and do not call this method yourself, you /// the [RenderSliverHelpers] mixin and do not call this method yourself, you
/// do not need to implement this method. /// do not need to implement this method.
@protected @protected
double childMainAxisPosition(@checked RenderObject child) { double childPosition(@checked RenderObject child) {
assert(() { assert(() {
throw new FlutterError('$runtimeType does not implement childPosition.'); throw new FlutterError('$runtimeType does not implement childPosition.');
}); });
return 0.0; return 0.0;
} }
@protected
double childCrossAxisPosition(@checked RenderObject child) => 0.0;
@override @override
void applyPaintTransform(RenderObject child, Matrix4 transform) { void applyPaintTransform(RenderObject child, Matrix4 transform) {
assert(() { assert(() {
@ -1003,25 +998,24 @@ abstract class RenderSliverHelpers implements RenderSliver {
/// This function takes care of converting the position from the sliver /// This function takes care of converting the position from the sliver
/// coordinate system to the cartesian coordinate system used by [RenderBox]. /// coordinate system to the cartesian coordinate system used by [RenderBox].
/// ///
/// This function relies on [childMainAxisPosition] to determine the position of /// This function relies on [childPosition] to determine the position of
/// child in question. /// child in question.
/// ///
/// Calling this for a child that is not visible is not valid. /// Calling this for a child that is not visible is not valid.
@protected @protected
bool hitTestBoxChild(HitTestResult result, RenderBox child, { @required double mainAxisPosition, @required double crossAxisPosition }) { bool hitTestBoxChild(HitTestResult result, RenderBox child, { @required double mainAxisPosition, @required double crossAxisPosition }) {
final bool rightWayUp = _getRightWayUp(constraints); final bool rightWayUp = _getRightWayUp(constraints);
double absolutePosition = mainAxisPosition - childMainAxisPosition(child); double absolutePosition = mainAxisPosition - childPosition(child);
final double absoluteCrossAxisPosition = crossAxisPosition - childCrossAxisPosition(child);
assert(constraints.axis != null); assert(constraints.axis != null);
switch (constraints.axis) { switch (constraints.axis) {
case Axis.horizontal: case Axis.horizontal:
if (!rightWayUp) if (!rightWayUp)
absolutePosition = child.size.width - absolutePosition; absolutePosition = child.size.width - absolutePosition;
return child.hitTest(result, position: new Point(absolutePosition, absoluteCrossAxisPosition)); return child.hitTest(result, position: new Point(absolutePosition, crossAxisPosition));
case Axis.vertical: case Axis.vertical:
if (!rightWayUp) if (!rightWayUp)
absolutePosition = child.size.height - absolutePosition; absolutePosition = child.size.height - absolutePosition;
return child.hitTest(result, position: new Point(absoluteCrossAxisPosition, absolutePosition)); return child.hitTest(result, position: new Point(crossAxisPosition, absolutePosition));
} }
return false; return false;
} }
@ -1029,27 +1023,25 @@ abstract class RenderSliverHelpers implements RenderSliver {
/// Utility function for [applyPaintTransform] for use when the children are /// Utility function for [applyPaintTransform] for use when the children are
/// [RenderBox] widgets. /// [RenderBox] widgets.
/// ///
/// This function turns the value returned by [childMainAxisPosition] and /// This function turns the value returned by [childPosition] for the child in
/// [childCrossAxisPosition]for the child in question into a translation that /// question into a translation that it then applies to the given matrix.
/// it then applies to the given matrix.
/// ///
/// Calling this for a child that is not visible is not valid. /// Calling this for a child that is not visible is not valid.
@protected @protected
void applyPaintTransformForBoxChild(RenderBox child, Matrix4 transform) { void applyPaintTransformForBoxChild(RenderBox child, Matrix4 transform) {
final bool rightWayUp = _getRightWayUp(constraints); final bool rightWayUp = _getRightWayUp(constraints);
double delta = childMainAxisPosition(child); double delta = childPosition(child);
final double crossAxisDelta = childCrossAxisPosition(child);
assert(constraints.axis != null); assert(constraints.axis != null);
switch (constraints.axis) { switch (constraints.axis) {
case Axis.horizontal: case Axis.horizontal:
if (!rightWayUp) if (!rightWayUp)
delta = geometry.paintExtent - child.size.width - delta; delta = geometry.paintExtent - child.size.width - delta;
transform.translate(delta, crossAxisDelta); transform.translate(delta, 0.0);
break; break;
case Axis.vertical: case Axis.vertical:
if (!rightWayUp) if (!rightWayUp)
delta = geometry.paintExtent - child.size.height - delta; delta = geometry.paintExtent - child.size.height - delta;
transform.translate(crossAxisDelta, delta); transform.translate(0.0, delta);
break; break;
} }
} }
@ -1846,7 +1838,7 @@ class RenderSliverToBoxAdapter extends RenderSliver with RenderObjectWithChildMi
} }
@override @override
double childMainAxisPosition(RenderBox child) { double childPosition(RenderBox child) {
return -constraints.scrollOffset; return -constraints.scrollOffset;
} }

18
packages/flutter/lib/src/rendering/sliver_app_bar.dart
View File

@ -132,7 +132,7 @@ abstract class RenderSliverAppBar extends RenderSliver with RenderObjectWithChil
/// ///
/// If there is no child, this should return 0.0. /// If there is no child, this should return 0.0.
@override @override
double childMainAxisPosition(@checked RenderObject child) => super.childMainAxisPosition(child); double childPosition(@checked RenderObject child) => super.childPosition(child);
@override @override
bool hitTestChildren(HitTestResult result, { @required double mainAxisPosition, @required double crossAxisPosition }) { bool hitTestChildren(HitTestResult result, { @required double mainAxisPosition, @required double crossAxisPosition }) {
@ -155,16 +155,16 @@ abstract class RenderSliverAppBar extends RenderSliver with RenderObjectWithChil
assert(constraints.axisDirection != null); assert(constraints.axisDirection != null);
switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) { switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
case AxisDirection.up: case AxisDirection.up:
offset += new Offset(0.0, geometry.paintExtent - childMainAxisPosition(child) - childExtent); offset += new Offset(0.0, geometry.paintExtent - childPosition(child) - childExtent);
break; break;
case AxisDirection.down: case AxisDirection.down:
offset += new Offset(0.0, childMainAxisPosition(child)); offset += new Offset(0.0, childPosition(child));
break; break;
case AxisDirection.left: case AxisDirection.left:
offset += new Offset(geometry.paintExtent - childMainAxisPosition(child) - childExtent, 0.0); offset += new Offset(geometry.paintExtent - childPosition(child) - childExtent, 0.0);
break; break;
case AxisDirection.right: case AxisDirection.right:
offset += new Offset(childMainAxisPosition(child), 0.0); offset += new Offset(childPosition(child), 0.0);
break; break;
} }
context.paintChild(child, offset); context.paintChild(child, offset);
@ -180,7 +180,7 @@ abstract class RenderSliverAppBar extends RenderSliver with RenderObjectWithChil
description.add('maxExtent: EXCEPTION (${e.runtimeType}) WHILE COMPUTING MAX EXTENT'); description.add('maxExtent: EXCEPTION (${e.runtimeType}) WHILE COMPUTING MAX EXTENT');
} }
try { try {
description.add('child position: ${childMainAxisPosition(child).toStringAsFixed(1)}'); description.add('child position: ${childPosition(child).toStringAsFixed(1)}');
} catch (e) { } catch (e) {
description.add('child position: EXCEPTION (${e.runtimeType}) WHILE COMPUTING CHILD POSITION'); description.add('child position: EXCEPTION (${e.runtimeType}) WHILE COMPUTING CHILD POSITION');
} }
@ -216,7 +216,7 @@ abstract class RenderSliverScrollingAppBar extends RenderSliverAppBar {
} }
@override @override
double childMainAxisPosition(RenderBox child) { double childPosition(RenderBox child) {
assert(child == this.child); assert(child == this.child);
return _childPosition; return _childPosition;
} }
@ -246,7 +246,7 @@ abstract class RenderSliverPinnedAppBar extends RenderSliverAppBar {
} }
@override @override
double childMainAxisPosition(RenderBox child) { double childPosition(RenderBox child) {
assert(child == this.child); assert(child == this.child);
return constraints?.overlap; return constraints?.overlap;
} }
@ -298,7 +298,7 @@ abstract class RenderSliverFloatingAppBar extends RenderSliverAppBar {
} }
@override @override
double childMainAxisPosition(RenderBox child) { double childPosition(RenderBox child) {
assert(child == this.child); assert(child == this.child);
return _childPosition; return _childPosition;
} }

13
packages/flutter/lib/src/rendering/sliver_block.dart
View File

@ -184,18 +184,17 @@ class RenderSliverBlock extends RenderSliverMultiBoxAdaptor {
collectGarbage(leadingGarbage, trailingGarbage); collectGarbage(leadingGarbage, trailingGarbage);
assert(debugAssertChildListIsNonEmptyAndContiguous()); assert(debugAssertChildListIsNonEmptyAndContiguous());
double estimatedMaxScrollOffset; double estimatedTotalExtent;
if (reachedEnd) { if (reachedEnd) {
estimatedMaxScrollOffset = endScrollOffset; estimatedTotalExtent = endScrollOffset;
} else { } else {
estimatedMaxScrollOffset = childManager.estimateMaxScrollOffset( estimatedTotalExtent = childManager.estimateScrollOffsetExtent(
constraints,
firstIndex: indexOf(firstChild), firstIndex: indexOf(firstChild),
lastIndex: indexOf(lastChild), lastIndex: indexOf(lastChild),
leadingScrollOffset: offsetOf(firstChild), leadingScrollOffset: offsetOf(firstChild),
trailingScrollOffset: endScrollOffset, trailingScrollOffset: endScrollOffset,
); );
assert(estimatedMaxScrollOffset >= endScrollOffset - offsetOf(firstChild)); assert(estimatedTotalExtent >= endScrollOffset - offsetOf(firstChild));
} }
final double paintedExtent = calculatePaintOffset( final double paintedExtent = calculatePaintOffset(
constraints, constraints,
@ -203,9 +202,9 @@ class RenderSliverBlock extends RenderSliverMultiBoxAdaptor {
to: endScrollOffset, to: endScrollOffset,
); );
geometry = new SliverGeometry( geometry = new SliverGeometry(
scrollExtent: estimatedMaxScrollOffset, scrollExtent: estimatedTotalExtent,
paintExtent: paintedExtent, paintExtent: paintedExtent,
maxPaintExtent: estimatedMaxScrollOffset, maxPaintExtent: estimatedTotalExtent,
// Conservative to avoid flickering away the clip during scroll. // Conservative to avoid flickering away the clip during scroll.
hasVisualOverflow: endScrollOffset > targetEndScrollOffset || constraints.scrollOffset > 0.0, hasVisualOverflow: endScrollOffset > targetEndScrollOffset || constraints.scrollOffset > 0.0,
); );

426
packages/flutter/lib/src/rendering/sliver_grid.dart
View File

@ -1,426 +0,0 @@
// 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 'dart:math' as math;
import 'package:meta/meta.dart';
import 'box.dart';
import 'object.dart';
import 'sliver.dart';
import 'sliver_multi_box_adaptor.dart';
/// Describes the placement of a child in a [RenderSliverGrid].
///
/// See also:
///
/// * [SliverGridDelegate.getGeometryForChildIndex], which returns this object
/// to describe the child's placement.
/// * [RenderSliverGrid], which uses this class during its
/// [RenderSliverGrid.performLayout] method.
class SliverGridGeometry {
/// Creates an object that describes the placement of a child in a [RenderSliverGrid].
const SliverGridGeometry({
this.scrollOffset,
this.crossAxisOffset,
this.mainAxisExtent,
this.crossAxisExtent,
});
/// The scroll offset of the leading edge of the child relative to the leading
/// edge of the parent.
final double scrollOffset;
/// The offset of the child in the non-scrolling axis.
///
/// If the scroll axis is vertical, this offset is from the left-most edge of
/// the parent to the left-most edge of the child. If the scroll axis is
/// horizontal, this offset is from the top-most edge of the parent to the
/// top-most edge of the child.
final double crossAxisOffset;
/// The extent of the child in the scrolling axis.
///
/// If the scroll axis is vertical, this extent is the child's height. If the
/// scroll axis is horizontal, this extent is the child's width.
final double mainAxisExtent;
/// The extent of the child in the non-scrolling axis.
///
/// If the scroll axis is vertical, this extent is the child's width. If the
/// scroll axis is horizontal, this extent is the child's height.
final double crossAxisExtent;
/// Returns a tight [BoxConstraints] that forces the child to have the
/// required size.
BoxConstraints getBoxConstraints(SliverConstraints constraints) {
return constraints.asBoxConstraints(
minExtent: mainAxisExtent,
maxExtent: mainAxisExtent,
crossAxisExtent: crossAxisExtent,
);
}
}
class SliverGridParentData extends SliverMultiBoxAdaptorParentData {
double crossAxisOffset;
@override
String toString() => 'crossAxisOffset=$crossAxisOffset; ${super.toString()}';
}
abstract class SliverGridDelegate {
/// Abstract const constructor. This constructor enables subclasses to provide
/// const constructors so that they can be used in const expressions.
const SliverGridDelegate();
int getMinChildIndexForScrollOffset(SliverConstraints constraints, double scrollOffset);
int getMaxChildIndexForScrollOffset(SliverConstraints constraints, double scrollOffset);
SliverGridGeometry getGeometryForChildIndex(SliverConstraints constraints, int index);
double estimateMaxScrollOffset(SliverConstraints constraints, int childCount);
bool shouldRelayout(@checked SliverGridDelegate oldDelegate);
}
class SliverGridDelegateWithFixedCrossAxisCount extends SliverGridDelegate {
const SliverGridDelegateWithFixedCrossAxisCount({
@required this.crossAxisCount,
this.mainAxisSpacing: 0.0,
this.crossAxisSpacing: 0.0,
this.childAspectRatio: 1.0,
});
/// The number of children in the cross axis.
final int crossAxisCount;
/// The number of logical pixels between each child along the main axis.
final double mainAxisSpacing;
/// The number of logical pixels between each child along the cross axis.
final double crossAxisSpacing;
/// The ratio of the cross-axis to the main-axis extent of each child.
final double childAspectRatio;
bool _debugAssertIsValid() {
assert(crossAxisCount > 0);
assert(mainAxisSpacing >= 0.0);
assert(crossAxisSpacing >= 0.0);
assert(childAspectRatio > 0.0);
return true;
}
double _getMainAxisStride(double crossAxisExtent) {
final double usableCrossAxisExtent = crossAxisExtent - crossAxisSpacing * (crossAxisCount - 1);
final double childCrossAxisExtent = usableCrossAxisExtent / crossAxisCount;
final double childMainAxisExtent = childCrossAxisExtent / childAspectRatio;
return childMainAxisExtent + mainAxisSpacing;
}
@override
int getMinChildIndexForScrollOffset(SliverConstraints constraints, double scrollOffset) {
assert(_debugAssertIsValid());
return crossAxisCount * (scrollOffset ~/ _getMainAxisStride(constraints.crossAxisExtent));
}
@override
int getMaxChildIndexForScrollOffset(SliverConstraints constraints, double scrollOffset) {
assert(_debugAssertIsValid());
final int mainAxisCount = (scrollOffset / _getMainAxisStride(constraints.crossAxisExtent)).ceil();
return math.max(0, crossAxisCount * mainAxisCount - 1);
}
@override
SliverGridGeometry getGeometryForChildIndex(SliverConstraints constraints, int index) {
final double usableCrossAxisExtent = constraints.crossAxisExtent - crossAxisSpacing * (crossAxisCount - 1);
final double childCrossAxisExtent = usableCrossAxisExtent / crossAxisCount;
final double childMainAxisExtent = childCrossAxisExtent / childAspectRatio;
final double mainAxisStride = childMainAxisExtent + mainAxisSpacing;
final double crossAxisStrid = childCrossAxisExtent + crossAxisSpacing;
assert(mainAxisStride == _getMainAxisStride(constraints.crossAxisExtent));
return new SliverGridGeometry(
scrollOffset: (index ~/ crossAxisCount) * mainAxisStride,
crossAxisOffset: (index % crossAxisCount) * crossAxisStrid,
mainAxisExtent: childMainAxisExtent,
crossAxisExtent: childCrossAxisExtent,
);
}
@override
double estimateMaxScrollOffset(SliverConstraints constraints, int childCount) {
if (childCount == null)
return null;
final int mainAxisCount = ((childCount - 1) / crossAxisCount).floor() + 1;
return _getMainAxisStride(constraints.crossAxisExtent) * mainAxisCount - mainAxisSpacing;
}
@override
bool shouldRelayout(SliverGridDelegateWithFixedCrossAxisCount oldDelegate) {
return oldDelegate.crossAxisCount != crossAxisCount
|| oldDelegate.mainAxisSpacing != mainAxisSpacing
|| oldDelegate.crossAxisSpacing != crossAxisSpacing
|| oldDelegate.childAspectRatio != childAspectRatio;
}
}
/// A [GridDelegate] that fills the width with a variable number of tiles.
///
/// This delegate will select a tile width that is as large as possible subject
/// to the following conditions:
///
/// - The tile width evenly divides the width of the grid.
/// - The tile width is at most [maxTileWidth].
class SliverGridDelegateWithMaxCrossAxisExtent extends SliverGridDelegate {
/// Creates a grid delegate that uses a max tile width.
///
/// The [maxTileWidth] argument must not be null.
const SliverGridDelegateWithMaxCrossAxisExtent({
@required this.maxCrossAxisExtent,
this.mainAxisSpacing: 0.0,
this.crossAxisSpacing: 0.0,
this.childAspectRatio: 1.0,
});
/// The number of children in the cross axis.
final double maxCrossAxisExtent;
/// The number of logical pixels between each child along the main axis.
final double mainAxisSpacing;
/// The number of logical pixels between each child along the cross axis.
final double crossAxisSpacing;
/// The ratio of the cross-axis to the main-axis extent of each child.
final double childAspectRatio;
bool _debugAssertIsValid() {
assert(maxCrossAxisExtent > 0.0);
assert(mainAxisSpacing >= 0.0);
assert(crossAxisSpacing >= 0.0);
assert(childAspectRatio > 0.0);
return true;
}
int _getCrossAxisCount(double crossAxisExtent) {
return (crossAxisExtent / (maxCrossAxisExtent + crossAxisSpacing)).ceil();
}
double _getMainAxisStride(double crossAxisExtent, int crossAxisCount) {
final double usableCrossAxisExtent = crossAxisExtent - crossAxisSpacing * (crossAxisCount - 1);
final double childCrossAxisExtent = usableCrossAxisExtent / crossAxisCount;
final double childMainAxisExtent = childCrossAxisExtent / childAspectRatio;
return childMainAxisExtent + mainAxisSpacing;
}
@override
int getMinChildIndexForScrollOffset(SliverConstraints constraints, double scrollOffset) {
assert(_debugAssertIsValid());
final double crossAxisExtent = constraints.crossAxisExtent;
final int crossAxisCount = _getCrossAxisCount(crossAxisExtent);
return crossAxisCount * (scrollOffset ~/ _getMainAxisStride(crossAxisExtent, crossAxisCount));
}
@override
int getMaxChildIndexForScrollOffset(SliverConstraints constraints, double scrollOffset) {
assert(_debugAssertIsValid());
final double crossAxisExtent = constraints.crossAxisExtent;
final int crossAxisCount = _getCrossAxisCount(crossAxisExtent);
final int mainAxisCount = (scrollOffset / _getMainAxisStride(crossAxisExtent, crossAxisCount)).ceil();
return math.max(0, crossAxisCount * mainAxisCount - 1);
}
@override
SliverGridGeometry getGeometryForChildIndex(SliverConstraints constraints, int index) {
final int crossAxisCount = _getCrossAxisCount(constraints.crossAxisExtent);
final double usableCrossAxisExtent = constraints.crossAxisExtent - crossAxisSpacing * (crossAxisCount - 1);
final double childCrossAxisExtent = usableCrossAxisExtent / crossAxisCount;
final double childMainAxisExtent = childCrossAxisExtent / childAspectRatio;
final double mainAxisStride = childMainAxisExtent + mainAxisSpacing;
final double crossAxisStrid = childCrossAxisExtent + crossAxisSpacing;
assert(mainAxisStride == _getMainAxisStride(constraints.crossAxisExtent, crossAxisCount));
return new SliverGridGeometry(
scrollOffset: (index ~/ crossAxisCount) * mainAxisStride,
crossAxisOffset: (index % crossAxisCount) * crossAxisStrid,
mainAxisExtent: childMainAxisExtent,
crossAxisExtent: childCrossAxisExtent,
);
}
@override
double estimateMaxScrollOffset(SliverConstraints constraints, int childCount) {
if (childCount == null)
return null;
final double crossAxisExtent = constraints.crossAxisExtent;
final int crossAxisCount = _getCrossAxisCount(crossAxisExtent);
final int mainAxisCount = ((childCount - 1) / crossAxisCount).floor() + 1;
return _getMainAxisStride(crossAxisExtent, crossAxisCount) * mainAxisCount - mainAxisSpacing;
}
@override
bool shouldRelayout(SliverGridDelegateWithMaxCrossAxisExtent oldDelegate) {
return oldDelegate.maxCrossAxisExtent != maxCrossAxisExtent
|| oldDelegate.mainAxisSpacing != mainAxisSpacing
|| oldDelegate.crossAxisSpacing != crossAxisSpacing
|| oldDelegate.childAspectRatio != childAspectRatio;
}
}
class RenderSliverGrid extends RenderSliverMultiBoxAdaptor {
RenderSliverGrid({
@required RenderSliverBoxChildManager childManager,
@required SliverGridDelegate gridDelegate,
}) : _gridDelegate = gridDelegate,
super(childManager: childManager) {
gridDelegate != null;
}
@override
void setupParentData(RenderObject child) {
if (child.parentData is! SliverGridParentData)
child.parentData = new SliverGridParentData();
}
SliverGridDelegate get gridDelegate => _gridDelegate;
SliverGridDelegate _gridDelegate;
set gridDelegate(SliverGridDelegate newDelegate) {
assert(newDelegate != null);
if (_gridDelegate == newDelegate)
return;
if (newDelegate.runtimeType != _gridDelegate.runtimeType ||
newDelegate.shouldRelayout(_gridDelegate))
markNeedsLayout();
_gridDelegate = newDelegate;
}
@override
double childCrossAxisPosition(RenderBox child) {
final SliverGridParentData childParentData = child.parentData;
return childParentData.crossAxisOffset;
}
@override
void performLayout() {
assert(childManager.debugAssertChildListLocked());
final double scrollOffset = constraints.scrollOffset;
assert(scrollOffset >= 0.0);
final double remainingPaintExtent = constraints.remainingPaintExtent;
assert(remainingPaintExtent >= 0.0);
final double targetEndScrollOffset = scrollOffset + remainingPaintExtent;
final int firstIndex = _gridDelegate.getMinChildIndexForScrollOffset(constraints, scrollOffset);
final int targetLastIndex = _gridDelegate.getMaxChildIndexForScrollOffset(constraints, targetEndScrollOffset);
if (firstChild != null) {
final int oldFirstIndex = indexOf(firstChild);
final int oldLastIndex = indexOf(lastChild);
final int leadingGarbage = (firstIndex - oldFirstIndex).clamp(0, childCount);
final int trailingGarbage = (oldLastIndex - targetLastIndex).clamp(0, childCount);
if (leadingGarbage + trailingGarbage > 0)
collectGarbage(leadingGarbage, trailingGarbage);
}
final SliverGridGeometry firstChildGridGeometry = _gridDelegate
.getGeometryForChildIndex(constraints, firstIndex);
double leadingScrollOffset = firstChildGridGeometry.scrollOffset;
double trailingScrollOffset = firstChildGridGeometry.scrollOffset;
if (firstChild == null) {
if (!addInitialChild(index: firstIndex,
scrollOffset: firstChildGridGeometry.scrollOffset)) {
// There are no children.
geometry = SliverGeometry.zero;
return;
}
}
RenderBox trailingChildWithLayout;
for (int index = indexOf(firstChild) - 1; index >= firstIndex; --index) {
final SliverGridGeometry gridGeometry = _gridDelegate
.getGeometryForChildIndex(constraints, index);
final RenderBox child = insertAndLayoutLeadingChild(
gridGeometry.getBoxConstraints(constraints));
final SliverGridParentData childParentData = child.parentData;
childParentData.scrollOffset = gridGeometry.scrollOffset;
childParentData.crossAxisOffset = gridGeometry.crossAxisOffset;
assert(childParentData.index == index);
trailingChildWithLayout ??= child;
if (gridGeometry.scrollOffset > trailingScrollOffset)
trailingScrollOffset = gridGeometry.scrollOffset;
}
assert(offsetOf(firstChild) <= scrollOffset);
if (trailingChildWithLayout == null) {
firstChild.layout(firstChildGridGeometry.getBoxConstraints(constraints));
final SliverGridParentData childParentData = firstChild.parentData;
childParentData.crossAxisOffset = firstChildGridGeometry.crossAxisOffset;
assert(childParentData.scrollOffset ==
firstChildGridGeometry.scrollOffset);
trailingChildWithLayout = firstChild;
}
for (int index = indexOf(trailingChildWithLayout) + 1; index <=
targetLastIndex; ++index) {
final SliverGridGeometry gridGeometry = _gridDelegate
.getGeometryForChildIndex(constraints, index);
final BoxConstraints childConstraints = gridGeometry.getBoxConstraints(
constraints);
RenderBox child = childAfter(trailingChildWithLayout);
if (child == null) {
child = insertAndLayoutChild(childConstraints, after: trailingChildWithLayout);
if (child == null) {
// We have run out of children.
break;
}
} else {
child.layout(childConstraints);
}
trailingChildWithLayout = child;
assert(child != null);
final SliverGridParentData childParentData = child.parentData;
childParentData.scrollOffset = gridGeometry.scrollOffset;
childParentData.crossAxisOffset = gridGeometry.crossAxisOffset;
assert(childParentData.index == index);
if (gridGeometry.scrollOffset > trailingScrollOffset)
trailingScrollOffset = gridGeometry.scrollOffset;
}
final int lastIndex = indexOf(lastChild);
assert(debugAssertChildListIsNonEmptyAndContiguous());
assert(indexOf(firstChild) == firstIndex);
assert(lastIndex <= targetLastIndex);
final double estimatedTotalExtent = childManager.estimateMaxScrollOffset(
constraints,
firstIndex: firstIndex,
lastIndex: lastIndex,
leadingScrollOffset: leadingScrollOffset,
trailingScrollOffset: trailingScrollOffset,
);
final double paintedExtent = calculatePaintOffset(
constraints,
from: leadingScrollOffset,
to: trailingScrollOffset,
);
geometry = new SliverGeometry(
scrollExtent: estimatedTotalExtent,
paintExtent: paintedExtent,
maxPaintExtent: estimatedTotalExtent,
// Conservative to avoid complexity.
hasVisualOverflow: true,
);
assert(childManager.debugAssertChildListLocked());
}
}

11
packages/flutter/lib/src/rendering/sliver_list.dart
View File

@ -14,9 +14,7 @@ class RenderSliverList extends RenderSliverMultiBoxAdaptor {
RenderSliverList({ RenderSliverList({
@required RenderSliverBoxChildManager childManager, @required RenderSliverBoxChildManager childManager,
double itemExtent, double itemExtent,
}) : _itemExtent = itemExtent, super(childManager: childManager) { }) : _itemExtent = itemExtent, super(childManager: childManager);
assert(itemExtent != null);
}
/// The main-axis extent of each item in the list. /// The main-axis extent of each item in the list.
double get itemExtent => _itemExtent; double get itemExtent => _itemExtent;
@ -107,8 +105,7 @@ class RenderSliverList extends RenderSliverMultiBoxAdaptor {
assert(indexOf(firstChild) == firstIndex); assert(indexOf(firstChild) == firstIndex);
assert(lastIndex <= targetLastIndex); assert(lastIndex <= targetLastIndex);
final double estimatedMaxScrollOffset = childManager.estimateMaxScrollOffset( final double estimatedTotalExtent = childManager.estimateScrollOffsetExtent(
constraints,
firstIndex: firstIndex, firstIndex: firstIndex,
lastIndex: lastIndex, lastIndex: lastIndex,
leadingScrollOffset: leadingScrollOffset, leadingScrollOffset: leadingScrollOffset,
@ -122,9 +119,9 @@ class RenderSliverList extends RenderSliverMultiBoxAdaptor {
); );
geometry = new SliverGeometry( geometry = new SliverGeometry(
scrollExtent: estimatedMaxScrollOffset, scrollExtent: estimatedTotalExtent,
paintExtent: paintedExtent, paintExtent: paintedExtent,
maxPaintExtent: estimatedMaxScrollOffset, maxPaintExtent: estimatedTotalExtent,
// Conservative to avoid flickering away the clip during scroll. // Conservative to avoid flickering away the clip during scroll.
hasVisualOverflow: lastIndex >= targetLastIndex || constraints.scrollOffset > 0.0, hasVisualOverflow: lastIndex >= targetLastIndex || constraints.scrollOffset > 0.0,
); );

29
packages/flutter/lib/src/rendering/sliver_multi_box_adaptor.dart
View File

@ -61,7 +61,7 @@ abstract class RenderSliverBoxChildManager {
/// Must return the total distance from the start of the child with the /// Must return the total distance from the start of the child with the
/// earliest possible index to the end of the child with the last possible /// earliest possible index to the end of the child with the last possible
/// index. /// index.
double estimateMaxScrollOffset(SliverConstraints constraints, { double estimateScrollOffsetExtent({
int firstIndex, int firstIndex,
int lastIndex, int lastIndex,
double leadingScrollOffset, double leadingScrollOffset,
@ -304,7 +304,7 @@ abstract class RenderSliverMultiBoxAdaptor extends RenderSliver
} }
@override @override
double childMainAxisPosition(RenderBox child) { double childPosition(RenderBox child) {
return offsetOf(child) - constraints.scrollOffset; return offsetOf(child) - constraints.scrollOffset;
} }
@ -319,46 +319,37 @@ abstract class RenderSliverMultiBoxAdaptor extends RenderSliver
return; return;
// offset is to the top-left corner, regardless of our axis direction. // offset is to the top-left corner, regardless of our axis direction.
// originOffset gives us the delta from the real origin to the origin in the axis direction. // originOffset gives us the delta from the real origin to the origin in the axis direction.
Offset mainAxisUnit, crossAxisUnit, originOffset; Offset unitOffset, originOffset;
bool addExtent; bool addExtent;
switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) { switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
case AxisDirection.up: case AxisDirection.up:
mainAxisUnit = const Offset(0.0, -1.0); unitOffset = const Offset(0.0, -1.0);
crossAxisUnit = const Offset(1.0, 0.0);
originOffset = offset + new Offset(0.0, geometry.paintExtent); originOffset = offset + new Offset(0.0, geometry.paintExtent);
addExtent = true; addExtent = true;
break; break;
case AxisDirection.right: case AxisDirection.right:
mainAxisUnit = const Offset(1.0, 0.0); unitOffset = const Offset(1.0, 0.0);
crossAxisUnit = const Offset(0.0, 1.0);
originOffset = offset; originOffset = offset;
addExtent = false; addExtent = false;
break; break;
case AxisDirection.down: case AxisDirection.down:
mainAxisUnit = const Offset(0.0, 1.0); unitOffset = const Offset(0.0, 1.0);
crossAxisUnit = const Offset(1.0, 0.0);
originOffset = offset; originOffset = offset;
addExtent = false; addExtent = false;
break; break;
case AxisDirection.left: case AxisDirection.left:
mainAxisUnit = const Offset(-1.0, 0.0); unitOffset = const Offset(-1.0, 0.0);
crossAxisUnit = const Offset(0.0, 1.0);
originOffset = offset + new Offset(geometry.paintExtent, 0.0); originOffset = offset + new Offset(geometry.paintExtent, 0.0);
addExtent = true; addExtent = true;
break; break;
} }
assert(mainAxisUnit != null); assert(unitOffset != null);
assert(addExtent != null); assert(addExtent != null);
RenderBox child = firstChild; RenderBox child = firstChild;
while (child != null) { while (child != null) {
final double mainAxisDelta = childMainAxisPosition(child); Offset childOffset = originOffset + unitOffset * childPosition(child);
final double crossAxisDelta = childCrossAxisPosition(child);
Offset childOffset = new Offset(
originOffset.dx + mainAxisUnit.dx * mainAxisDelta + crossAxisUnit.dx * crossAxisDelta,
originOffset.dy + mainAxisUnit.dy * mainAxisDelta + crossAxisUnit.dy * crossAxisDelta,
);
if (addExtent) if (addExtent)
childOffset += mainAxisUnit * paintExtentOf(child); childOffset += unitOffset * paintExtentOf(child);
context.paintChild(child, childOffset); context.paintChild(child, childOffset);
child = childAfter(child); child = childAfter(child);
} }

11
packages/flutter/lib/src/rendering/sliver_padding.dart
View File

@ -262,24 +262,17 @@ class RenderSliverPadding extends RenderSliver with RenderObjectWithChildMixin<R
@override @override
bool hitTestChildren(HitTestResult result, { @required double mainAxisPosition, @required double crossAxisPosition }) { bool hitTestChildren(HitTestResult result, { @required double mainAxisPosition, @required double crossAxisPosition }) {
if (child.geometry.hitTestExtent > 0.0) if (child.geometry.hitTestExtent > 0.0)
return child.hitTest(result, mainAxisPosition: mainAxisPosition - childMainAxisPosition(child), crossAxisPosition: crossAxisPosition - childCrossAxisPosition(child)); return child.hitTest(result, mainAxisPosition: mainAxisPosition - childPosition(child), crossAxisPosition: crossAxisPosition - startPadding);
return false; return false;
} }
@override @override
double childMainAxisPosition(RenderSliver child) { double childPosition(RenderSliver child) {
assert(child != null); assert(child != null);
assert(child == this.child); assert(child == this.child);
return calculatePaintOffset(constraints, from: 0.0, to: beforePadding); return calculatePaintOffset(constraints, from: 0.0, to: beforePadding);
} }
@override
double childCrossAxisPosition(RenderSliver child) {
assert(child != null);
assert(child == this.child);
return startPadding;
}
@override @override
void applyPaintTransform(RenderObject child, Matrix4 transform) { void applyPaintTransform(RenderObject child, Matrix4 transform) {
assert(child != null); assert(child != null);

125
packages/flutter/lib/src/widgets/scroll_view.dart
View File

@ -3,31 +3,21 @@
// found in the LICENSE file. // found in the LICENSE file.
import 'package:flutter/rendering.dart'; import 'package:flutter/rendering.dart';
import 'package:meta/meta.dart';
import 'framework.dart'; import 'framework.dart';
import 'basic.dart'; import 'basic.dart';
import 'scrollable.dart'; import 'scrollable.dart';
import 'sliver.dart'; import 'sliver.dart';
AxisDirection _getDirection(BuildContext context, Axis scrollDirection) {
// TODO(abarth): Consider reading direction.
switch (scrollDirection) {
case Axis.horizontal:
return AxisDirection.right;
case Axis.vertical:
return AxisDirection.down;
}
return null;
}
class ScrollView extends StatelessWidget { class ScrollView extends StatelessWidget {
ScrollView({ ScrollView({
Key key, Key key,
this.padding, this.padding,
this.scrollDirection: Axis.vertical, this.scrollDirection: Axis.vertical,
this.anchor: 0.0,
this.initialScrollOffset: 0.0, this.initialScrollOffset: 0.0,
this.itemExtent, this.itemExtent,
this.center,
this.children, this.children,
}) : super(key: key); }) : super(key: key);
@ -35,109 +25,50 @@ class ScrollView extends StatelessWidget {
final Axis scrollDirection; final Axis scrollDirection;
final double anchor;
final double initialScrollOffset; final double initialScrollOffset;
final double itemExtent; final double itemExtent;
final Key center;
final List<Widget> children; final List<Widget> children;
Widget _buildChildLayout() { AxisDirection _getDirection(BuildContext context) {
// TODO(abarth): Consider reading direction.
switch (scrollDirection) {
case Axis.horizontal:
return AxisDirection.right;
case Axis.vertical:
return AxisDirection.down;
}
return null;
}
@override
Widget build(BuildContext context) {
final SliverChildListDelegate delegate = new SliverChildListDelegate(children); final SliverChildListDelegate delegate = new SliverChildListDelegate(children);
if (itemExtent != null) { Widget sliver;
return new SliverList(
if (itemExtent == null) {
sliver = new SliverBlock(delegate: delegate);
} else {
sliver = new SliverList(
delegate: delegate, delegate: delegate,
itemExtent: itemExtent, itemExtent: itemExtent,
); );
} }
return new SliverBlock(delegate: delegate);
}
@override
Widget build(BuildContext context) {
Widget sliver = _buildChildLayout();
if (padding != null) if (padding != null)
sliver = new SliverPadding(padding: padding, child: sliver); sliver = new SliverPadding(padding: padding, child: sliver);
return new ScrollableViewport2( return new ScrollableViewport2(
axisDirection: _getDirection(context, scrollDirection), axisDirection: _getDirection(context),
initialScrollOffset: initialScrollOffset, anchor: anchor,
slivers: <Widget>[ sliver ],
);
}
}
class ScrollGrid extends StatelessWidget {
ScrollGrid({
Key key,
this.padding,
this.scrollDirection: Axis.vertical,
this.initialScrollOffset: 0.0,
this.gridDelegate,
this.children,
}) : super(key: key);
ScrollGrid.count({
Key key,
this.padding,
this.scrollDirection: Axis.vertical,
this.initialScrollOffset: 0.0,
@required int crossAxisCount,
double mainAxisSpacing: 0.0,
double crossAxisSpacing: 0.0,
double childAspectRatio: 1.0,
this.children,
}) : gridDelegate = new SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: crossAxisCount,
mainAxisSpacing: mainAxisSpacing,
crossAxisSpacing: crossAxisSpacing,
childAspectRatio: childAspectRatio,
), super(key: key);
ScrollGrid.extent({
Key key,
this.padding,
this.scrollDirection: Axis.vertical,
this.initialScrollOffset: 0.0,
@required double maxCrossAxisExtent,
double mainAxisSpacing: 0.0,
double crossAxisSpacing: 0.0,
double childAspectRatio: 1.0,
this.children,
}) : gridDelegate = new SliverGridDelegateWithMaxCrossAxisExtent(
maxCrossAxisExtent: maxCrossAxisExtent,
mainAxisSpacing: mainAxisSpacing,
crossAxisSpacing: crossAxisSpacing,
childAspectRatio: childAspectRatio,
), super(key: key);
final EdgeInsets padding;
final Axis scrollDirection;
final double initialScrollOffset;
final SliverGridDelegate gridDelegate;
final List<Widget> children;
@override
Widget build(BuildContext context) {
final SliverChildListDelegate delegate = new SliverChildListDelegate(children);
Widget sliver = new SliverGrid(
delegate: delegate,
gridDelegate: gridDelegate,
);
if (padding != null)
sliver = new SliverPadding(padding: padding, child: sliver);
return new ScrollableViewport2(
axisDirection: _getDirection(context, scrollDirection),
initialScrollOffset: initialScrollOffset, initialScrollOffset: initialScrollOffset,
center: center,
slivers: <Widget>[ sliver ], slivers: <Widget>[ sliver ],
); );
} }

120
packages/flutter/lib/src/widgets/sliver.dart
View File

@ -10,11 +10,6 @@ import 'package:flutter/rendering.dart';
import 'framework.dart'; import 'framework.dart';
import 'basic.dart'; import 'basic.dart';
export 'package:flutter/rendering.dart' show
SliverGridDelegate,
SliverGridDelegateWithFixedCrossAxisCount,
SliverGridDelegateWithMaxCrossAxisExtent;
abstract class SliverChildDelegate { abstract class SliverChildDelegate {
/// Abstract const constructor. This constructor enables subclasses to provide /// Abstract const constructor. This constructor enables subclasses to provide
/// const constructors so that they can be used in const expressions. /// const constructors so that they can be used in const expressions.
@ -22,23 +17,24 @@ abstract class SliverChildDelegate {
Widget build(BuildContext context, int index); Widget build(BuildContext context, int index);
/// Returns an estimate of the number of children this delegate will build. bool shouldRebuild(@checked SliverChildDelegate oldDelegate);
///
/// Used to estimate the maximum scroll offset if [estimateMaxScrollOffset]
/// returns null.
///
/// Return null if there are an unbounded number of children or if it would
/// be too difficult to estimate the number of children.
int get estimatedChildCount => null;
double estimateMaxScrollOffset( int get childCount;
double estimateScrollOffsetExtent(
int firstIndex, int firstIndex,
int lastIndex, int lastIndex,
double leadingScrollOffset, double leadingScrollOffset,
double trailingScrollOffset, double trailingScrollOffset,
) => null; ) {
final int childCount = this.childCount;
bool shouldRebuild(@checked SliverChildDelegate oldDelegate); if (lastIndex == childCount - 1)
return trailingScrollOffset;
final int reifiedCount = lastIndex - firstIndex + 1;
final double averageExtent = (trailingScrollOffset - leadingScrollOffset) / reifiedCount;
final int remainingCount = childCount - lastIndex - 1;
return trailingScrollOffset + averageExtent * remainingCount;
}
} }
// /// // ///
@ -68,13 +64,13 @@ class SliverChildListDelegate extends SliverChildDelegate {
return children[index]; return children[index];
} }
@override
int get estimatedChildCount => children.length;
@override @override
bool shouldRebuild(@checked SliverChildListDelegate oldDelegate) { bool shouldRebuild(@checked SliverChildListDelegate oldDelegate) {
return children != oldDelegate.children; return children != oldDelegate.children;
} }
@override
int get childCount => children.length;
} }
abstract class SliverMultiBoxAdaptorWidget extends RenderObjectWidget { abstract class SliverMultiBoxAdaptorWidget extends RenderObjectWidget {
@ -93,22 +89,6 @@ abstract class SliverMultiBoxAdaptorWidget extends RenderObjectWidget {
@override @override
RenderSliverMultiBoxAdaptor createRenderObject(BuildContext context); RenderSliverMultiBoxAdaptor createRenderObject(BuildContext context);
double estimateMaxScrollOffset(
SliverConstraints constraints,
int firstIndex,
int lastIndex,
double leadingScrollOffset,
double trailingScrollOffset,
) {
assert(lastIndex >= firstIndex);
return delegate.estimateMaxScrollOffset(
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset,
);
}
@override @override
void debugFillDescription(List<String> description) { void debugFillDescription(List<String> description) {
super.debugFillDescription(description); super.debugFillDescription(description);
@ -150,44 +130,6 @@ class SliverList extends SliverMultiBoxAdaptorWidget {
} }
} }
class SliverGrid extends SliverMultiBoxAdaptorWidget {
SliverGrid({
Key key,
@required SliverChildDelegate delegate,
@required this.gridDelegate,
}) : super(key: key, delegate: delegate);
final SliverGridDelegate gridDelegate;
@override
RenderSliverGrid createRenderObject(BuildContext context) {
final SliverMultiBoxAdaptorElement element = context;
return new RenderSliverGrid(childManager: element, gridDelegate: gridDelegate);
}
@override
void updateRenderObject(BuildContext context, RenderSliverGrid renderObject) {
renderObject.gridDelegate = gridDelegate;
}
@override
double estimateMaxScrollOffset(
SliverConstraints constraints,
int firstIndex,
int lastIndex,
double leadingScrollOffset,
double trailingScrollOffset,
) {
return super.estimateMaxScrollOffset(
constraints,
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset,
) ?? gridDelegate.estimateMaxScrollOffset(constraints, delegate.estimatedChildCount);
}
}
class SliverMultiBoxAdaptorElement extends RenderObjectElement implements RenderSliverBoxChildManager { class SliverMultiBoxAdaptorElement extends RenderObjectElement implements RenderSliverBoxChildManager {
SliverMultiBoxAdaptorElement(SliverMultiBoxAdaptorWidget widget) : super(widget); SliverMultiBoxAdaptorElement(SliverMultiBoxAdaptorWidget widget) : super(widget);
@ -299,41 +241,19 @@ class SliverMultiBoxAdaptorElement extends RenderObjectElement implements Render
}); });
} }
double _extrapolateMaxScrollOffset(
int firstIndex,
int lastIndex,
double leadingScrollOffset,
double trailingScrollOffset,
) {
final int childCount = widget.delegate.estimatedChildCount;
if (childCount == null)
return double.INFINITY;
if (lastIndex == childCount - 1)
return trailingScrollOffset;
final int reifiedCount = lastIndex - firstIndex + 1;
final double averageExtent = (trailingScrollOffset - leadingScrollOffset) / reifiedCount;
final int remainingCount = childCount - lastIndex - 1;
return trailingScrollOffset + averageExtent * remainingCount;
}
@override @override
double estimateMaxScrollOffset(SliverConstraints constraints, { double estimateScrollOffsetExtent({
int firstIndex, int firstIndex,
int lastIndex, int lastIndex,
double leadingScrollOffset, double leadingScrollOffset,
double trailingScrollOffset, double trailingScrollOffset,
}) { }) {
return widget.estimateMaxScrollOffset( assert(lastIndex >= firstIndex);
constraints, return widget.delegate.estimateScrollOffsetExtent(
firstIndex, firstIndex,
lastIndex, lastIndex,
leadingScrollOffset, leadingScrollOffset,
trailingScrollOffset, trailingScrollOffset
) ?? _extrapolateMaxScrollOffset(
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset,
); );
} }

2
packages/flutter/test/rendering/slivers_block_test.dart
View File

@ -43,7 +43,7 @@ class TestRenderSliverBoxChildManager extends RenderSliverBoxChildManager {
} }
@override @override
double estimateMaxScrollOffset(SliverConstraints constraints, { double estimateScrollOffsetExtent({
int firstIndex, int firstIndex,
int lastIndex, int lastIndex,
double leadingScrollOffset, double leadingScrollOffset,

22
packages/flutter/test/widgets/block_test.dart
View File

@ -3,7 +3,6 @@
// found in the LICENSE file. // found in the LICENSE file.
import 'package:flutter_test/flutter_test.dart'; import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart'; import 'package:flutter/widgets.dart';
final Key blockKey = new Key('test'); final Key blockKey = new Key('test');
@ -121,7 +120,7 @@ void main() {
expect(key.currentState.scrollOffset, 0.0); expect(key.currentState.scrollOffset, 0.0);
}); });
testWidgets('SliverBlockChildListDelegate.estimateMaxScrollOffset hits end', (WidgetTester tester) async { testWidgets('SliverBlockChildListDelegate.estimateScrollOffsetExtent hits end', (WidgetTester tester) async {
SliverChildListDelegate delegate = new SliverChildListDelegate(<Widget>[ SliverChildListDelegate delegate = new SliverChildListDelegate(<Widget>[
new Container(), new Container(),
new Container(), new Container(),
@ -130,23 +129,6 @@ void main() {
new Container(), new Container(),
]); ]);
await tester.pumpWidget(new ScrollableViewport2( expect(delegate.estimateScrollOffsetExtent(3, 4, 25.0, 26.0), equals(26.0));
slivers: <Widget>[
new SliverBlock(
delegate: delegate,
),
],
));
final SliverMultiBoxAdaptorElement element = tester.element(find.byType(SliverBlock));
final double maxScrollOffset = element.estimateMaxScrollOffset(
null,
firstIndex: 3,
lastIndex: 4,
leadingScrollOffset: 25.0,
trailingScrollOffset: 26.0
);
expect(maxScrollOffset, equals(26.0));
}); });
} }

306
packages/flutter/test/widgets/scroll_grid_test.dart
View File

@ -1,306 +0,0 @@
// 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/widgets.dart';
import 'states.dart';
void main() {
testWidgets('Empty ScrollGrid', (WidgetTester tester) async {
await tester.pumpWidget(new ScrollGrid.count(
crossAxisCount: 4,
children: const <Widget>[],
));
});
testWidgets('ScrollGrid.count control test', (WidgetTester tester) async {
List<String> log = <String>[];
await tester.pumpWidget(new ScrollGrid.count(
crossAxisCount: 4,
children: kStates.map((String state) {
return new GestureDetector(
onTap: () {
log.add(state);
},
child: new Container(
decoration: const BoxDecoration(
backgroundColor: const Color(0xFF0000FF),
),
child: new Text(state),
),
);
}).toList(),
));
expect(tester.getSize(find.text('Arkansas')), equals(const Size(200.0, 200.0)));
for (int i = 0; i < 8; ++i) {
await tester.tap(find.text(kStates[i]));
expect(log, equals(<String>[kStates[i]]));
log.clear();
}
expect(find.text(kStates[12]), findsNothing);
expect(find.text('Nevada'), findsNothing);
await tester.scroll(find.text('Arkansas'), const Offset(0.0, -200.0));
await tester.pump();
for (int i = 0; i < 4; ++i)
expect(find.text(kStates[i]), findsNothing);
for (int i = 4; i < 12; ++i) {
await tester.tap(find.text(kStates[i]));
expect(log, equals(<String>[kStates[i]]));
log.clear();
}
await tester.scroll(find.text('Delaware'), const Offset(0.0, -4000.0));
await tester.pump();
expect(find.text('Alabama'), findsNothing);
expect(find.text('Pennsylvania'), findsNothing);
expect(tester.getCenter(find.text('Tennessee')),
equals(const Point(300.0, 100.0)));
await tester.tap(find.text('Tennessee'));
expect(log, equals(<String>['Tennessee']));
log.clear();
await tester.scroll(find.text('Tennessee'), const Offset(0.0, 200.0));
await tester.pump();
await tester.tap(find.text('Tennessee'));
expect(log, equals(<String>['Tennessee']));
log.clear();
await tester.tap(find.text('Pennsylvania'));
expect(log, equals(<String>['Pennsylvania']));
log.clear();
});
testWidgets('ScrollGrid.extent control test', (WidgetTester tester) async {
List<String> log = <String>[];
await tester.pumpWidget(new ScrollGrid.extent(
maxCrossAxisExtent: 200.0,
children: kStates.map((String state) {
return new GestureDetector(
onTap: () {
log.add(state);
},
child: new Container(
decoration: const BoxDecoration(
backgroundColor: const Color(0xFF0000FF),
),
child: new Text(state),
),
);
}).toList(),
));
expect(tester.getSize(find.text('Arkansas')), equals(const Size(200.0, 200.0)));
for (int i = 0; i < 8; ++i) {
await tester.tap(find.text(kStates[i]));
expect(log, equals(<String>[kStates[i]]));
log.clear();
}
expect(find.text('Nevada'), findsNothing);
await tester.scroll(find.text('Arkansas'), const Offset(0.0, -4000.0));
await tester.pump();
expect(find.text('Alabama'), findsNothing);
expect(tester.getCenter(find.text('Tennessee')),
equals(const Point(300.0, 100.0)));
await tester.tap(find.text('Tennessee'));
expect(log, equals(<String>['Tennessee']));
log.clear();
});
testWidgets('ScrollGrid large scroll jump', (WidgetTester tester) async {
List<int> log = <int>[];
await tester.pumpWidget(
new ScrollGrid.extent(
scrollDirection: Axis.horizontal,
maxCrossAxisExtent: 200.0,
childAspectRatio: 0.75,
children: new List<Widget>.generate(80, (int i) {
return new Builder(
builder: (BuildContext context) {
log.add(i);
return new Container(
child: new Text('$i'),
);
}
);
}),
),
);
expect(tester.getSize(find.text('4')), equals(const Size(200.0 / 0.75, 200.0)));
expect(log, equals(<int>[
0, 1, 2, // col 0
3, 4, 5, // col 1
6, 7, 8, // col 2
]));
log.clear();
Scrollable2State state = tester.state(find.byType(Scrollable2));
AbsoluteScrollPosition position = state.position;
position.jumpTo(3025.0);
expect(log, isEmpty);
await tester.pump();
expect(log, equals(<int>[
33, 34, 35, // col 11
36, 37, 38, // col 12
39, 40, 41, // col 13
42, 43, 44, // col 14
]));
log.clear();
position.jumpTo(975.0);
expect(log, isEmpty);
await tester.pump();
expect(log, equals(<int>[
9, 10, 11, // col 3
12, 13, 14, // col 4
15, 16, 17, // col 5
18, 19, 20, // col 6
]));
log.clear();
});
testWidgets('ScrollGrid - change crossAxisCount', (WidgetTester tester) async {
List<int> log = <int>[];
await tester.pumpWidget(
new ScrollGrid(
gridDelegate: new SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 4,
),
children: new List<Widget>.generate(40, (int i) {
return new Builder(
builder: (BuildContext context) {
log.add(i);
return new Container(
child: new Text('$i'),
);
}
);
}),
),
);
expect(tester.getSize(find.text('4')), equals(const Size(200.0, 200.0)));
expect(log, equals(<int>[
0, 1, 2, 3, // row 0
4, 5, 6, 7, // row 1
8, 9, 10, 11, // row 2
]));
log.clear();
await tester.pumpWidget(
new ScrollGrid(
gridDelegate: new SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 2,
),
children: new List<Widget>.generate(40, (int i) {
return new Builder(
builder: (BuildContext context) {
log.add(i);
return new Container(
child: new Text('$i'),
);
}
);
}),
),
);
expect(log, equals(<int>[
0, 1, 2, 3, // row 0
4, 5, 6, 7, // row 1
8, 9, 10, 11, // row 2
]));
log.clear();
expect(tester.getSize(find.text('3')), equals(const Size(400.0, 400.0)));
expect(find.text('4'), findsNothing);
});
testWidgets('ScrollGrid - change maxChildCrossAxisExtent', (WidgetTester tester) async {
List<int> log = <int>[];
await tester.pumpWidget(
new ScrollGrid(
gridDelegate: new SliverGridDelegateWithMaxCrossAxisExtent(
maxCrossAxisExtent: 200.0,
),
children: new List<Widget>.generate(40, (int i) {
return new Builder(
builder: (BuildContext context) {
log.add(i);
return new Container(
child: new Text('$i'),
);
}
);
}),
),
);
expect(tester.getSize(find.text('4')), equals(const Size(200.0, 200.0)));
expect(log, equals(<int>[
0, 1, 2, 3, // row 0
4, 5, 6, 7, // row 1
8, 9, 10, 11, // row 2
]));
log.clear();
await tester.pumpWidget(
new ScrollGrid(
gridDelegate: new SliverGridDelegateWithMaxCrossAxisExtent(
maxCrossAxisExtent: 400.0,
),
children: new List<Widget>.generate(40, (int i) {
return new Builder(
builder: (BuildContext context) {
log.add(i);
return new Container(
child: new Text('$i'),
);
}
);
}),
),
);
expect(log, equals(<int>[
0, 1, 2, 3, // row 0
4, 5, 6, 7, // row 1
8, 9, 10, 11, // row 2
]));
log.clear();
expect(tester.getSize(find.text('3')), equals(const Size(400.0, 400.0)));
expect(find.text('4'), findsNothing);
});
}

57
packages/flutter/test/widgets/scroll_view_test.dart
View File

@ -5,14 +5,65 @@
import 'package:flutter_test/flutter_test.dart'; import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/widgets.dart'; import 'package:flutter/widgets.dart';
import 'states.dart'; const List<String> _kStates = const <String>[
'Alabama',
'Alaska',
'Arizona',
'Arkansas',
'California',
'Colorado',
'Connecticut',
'Delaware',
'Florida',
'Georgia',
'Hawaii',
'Idaho',
'Illinois',
'Indiana',
'Iowa',
'Kansas',
'Kentucky',
'Louisiana',
'Maine',
'Maryland',
'Massachusetts',
'Michigan',
'Minnesota',
'Mississippi',
'Missouri',
'Montana',
'Nebraska',
'Nevada',
'New Hampshire',
'New Jersey',
'New Mexico',
'New York',
'North Carolina',
'North Dakota',
'Ohio',
'Oklahoma',
'Oregon',
'Pennsylvania',
'Rhode Island',
'South Carolina',
'South Dakota',
'Tennessee',
'Texas',
'Utah',
'Vermont',
'Virginia',
'Washington',
'West Virginia',
'Wisconsin',
'Wyoming',
];
void main() { void main() {
testWidgets('ScrollView control test', (WidgetTester tester) async { testWidgets('ScrollView control test', (WidgetTester tester) async {
List<String> log = <String>[]; List<String> log = <String>[];
await tester.pumpWidget(new ScrollView( await tester.pumpWidget(new ScrollView(
children: kStates.map<Widget>((String state) { children: _kStates.map<Widget>((String state) {
return new GestureDetector( return new GestureDetector(
onTap: () { onTap: () {
log.add(state); log.add(state);
@ -48,7 +99,7 @@ void main() {
testWidgets('ScrollView restart ballistic activity out of range', (WidgetTester tester) async { testWidgets('ScrollView restart ballistic activity out of range', (WidgetTester tester) async {
Widget buildScrollView(int n) { Widget buildScrollView(int n) {
return new ScrollView( return new ScrollView(
children: kStates.take(n).map<Widget>((String state) { children: _kStates.take(n).map<Widget>((String state) {
return new Container( return new Container(
height: 200.0, height: 200.0,
decoration: const BoxDecoration( decoration: const BoxDecoration(

56
packages/flutter/test/widgets/states.dart
View File

@ -1,56 +0,0 @@
// 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.
const List<String> kStates = const <String>[
'Alabama',
'Alaska',
'Arizona',
'Arkansas',
'California',
'Colorado',
'Connecticut',
'Delaware',
'Florida',
'Georgia',
'Hawaii',
'Idaho',
'Illinois',
'Indiana',
'Iowa',
'Kansas',
'Kentucky',
'Louisiana',
'Maine',
'Maryland',
'Massachusetts',
'Michigan',
'Minnesota',
'Mississippi',
'Missouri',
'Montana',
'Nebraska',
'Nevada',
'New Hampshire',
'New Jersey',
'New Mexico',
'New York',
'North Carolina',
'North Dakota',
'Ohio',
'Oklahoma',
'Oregon',
'Pennsylvania',
'Rhode Island',
'South Carolina',
'South Dakota',
'Tennessee',
'Texas',
'Utah',
'Vermont',
'Virginia',
'Washington',
'West Virginia',
'Wisconsin',
'Wyoming',
];