public float estimateMaxScrollOffset(SliverConstraints constraints,
int firstIndex = 0,
int lastIndex = 0,
float leadingScrollOffset = 0,
float trailingScrollOffset = 0
)
{
int?childCount = this.childCount;
if (childCount == null)
{
return(float.PositiveInfinity);
}
return(widget.estimateMaxScrollOffset(
constraints,
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset
) ?? _extrapolateMaxScrollOffset(
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset,
childCount.Value
));
}
public BoxConstraints getBoxConstraints(SliverConstraints constraints)
{
return(constraints.asBoxConstraints(
minExtent: this.mainAxisExtent ?? 0.0f,
maxExtent: this.mainAxisExtent ?? 0.0f,
crossAxisExtent: this.crossAxisExtent ?? 0.0f
));
}
public override SliverGridLayout getLayout(SliverConstraints constraints)
{
float tileWidth = (constraints.crossAxisExtent - _spacing) / 2.0f;
const float tileHeight = 40.0f + 144.0f + 40.0f;
return(new _ShrineGridLayout(
tileWidth: tileWidth,
tileHeight: tileHeight,
rowStride: tileHeight + _spacing,
columnStride: tileWidth + _spacing
));
}
public virtual float?estimateMaxScrollOffset(
SliverConstraints constraints,
int firstIndex,
int lastIndex,
float leadingScrollOffset,
float trailingScrollOffset
)
{
D.assert(lastIndex >= firstIndex);
return(del.estimateMaxScrollOffset(
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset
));
}
public override SliverGridLayout getLayout(SliverConstraints constraints)
{
float tileWidth =
(constraints.crossAxisExtent -
(material_._yearPickerColumnCount - 1) * material_._yearPickerRowSpacing) /
material_._yearPickerColumnCount;
return(new SliverGridRegularTileLayout(
childCrossAxisExtent: tileWidth,
childMainAxisExtent: material_._yearPickerRowHeight,
crossAxisCount: material_._yearPickerColumnCount,
crossAxisStride: tileWidth + material_._yearPickerRowSpacing,
mainAxisStride: material_._yearPickerRowHeight,
reverseCrossAxis: AxisUtils.axisDirectionIsReversed(constraints.crossAxisDirection)
));
}
public override SliverGridLayout getLayout(SliverConstraints constraints)
{
const int columnCount = daysPerWeek;
float tileWidth = constraints.crossAxisExtent / columnCount;
float tileHeight = Mathf.Min(material_._dayPickerRowHeight,
constraints.viewportMainAxisExtent / material_._maxDayPickerRowCount);
return(new SliverGridRegularTileLayout(
childCrossAxisExtent: tileWidth,
childMainAxisExtent: tileHeight,
crossAxisCount: columnCount,
crossAxisStride: tileWidth,
mainAxisStride: tileHeight,
reverseCrossAxis: AxisUtils.axisDirectionIsReversed(constraints.crossAxisDirection)
));
}
public double?estimateMaxScrollOffset(
SliverConstraints constraints,
int firstIndex,
int lastIndex,
double leadingScrollOffset,
double trailingScrollOffset
)
{
D.assert(lastIndex >= firstIndex);
return(this.del.estimateMaxScrollOffset(
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset
));
}
public override float?estimateMaxScrollOffset(
SliverConstraints constraints,
int firstIndex,
int lastIndex,
float leadingScrollOffset,
float trailingScrollOffset
)
{
return(base.estimateMaxScrollOffset(
constraints,
firstIndex,
lastIndex,
leadingScrollOffset,
trailingScrollOffset
) ?? gridDelegate.getLayout(constraints)
.computeMaxScrollOffset(del.estimatedChildCount ?? 0));
}
public override SliverGridLayout getLayout(SliverConstraints constraints)
{
D.assert(this._debugAssertIsValid());
float usableCrossAxisExtent =
constraints.crossAxisExtent - this.crossAxisSpacing * (this.crossAxisCount - 1);
float childCrossAxisExtent = usableCrossAxisExtent / this.crossAxisCount;
float childMainAxisExtent = childCrossAxisExtent / this.childAspectRatio;
return(new SliverGridRegularTileLayout(
crossAxisCount: this.crossAxisCount,
mainAxisStride: childMainAxisExtent + this.mainAxisSpacing,
crossAxisStride: childCrossAxisExtent + this.crossAxisSpacing,
childMainAxisExtent: childMainAxisExtent,
childCrossAxisExtent: childCrossAxisExtent,
reverseCrossAxis: AxisUtils.axisDirectionIsReversed(constraints.crossAxisDirection)
));
}
public override SliverGridLayout getLayout(SliverConstraints constraints)
{
const int columnCount = 7; // DateTime.daysPerWeek = 7
float tileWidth = constraints.crossAxisExtent / columnCount;
float tileHeight = Mathf.Min(
DatePickerUtils._kDayPickerRowHeight,
constraints.viewportMainAxisExtent / (DatePickerUtils._kMaxDayPickerRowCount + 1)
);
return(new SliverGridRegularTileLayout(
crossAxisCount: columnCount,
mainAxisStride: tileHeight,
crossAxisStride: tileWidth,
childMainAxisExtent: tileHeight,
childCrossAxisExtent: tileWidth,
reverseCrossAxis: AxisUtils.axisDirectionIsReversed(constraints.crossAxisDirection)
));
}
protected override void performLayout()
{
SliverConstraints constraints = this.constraints;
D.assert(constraints.axisDirection == AxisDirection.down);
D.assert(constraints.growthDirection == GrowthDirection.forward);
float layoutExtent =
(_hasLayoutExtent ? 1.0f : 0.0f) * _refreshIndicatorExtent;
if (layoutExtent != layoutExtentOffsetCompensation)
{
geometry = new SliverGeometry(
scrollOffsetCorrection: layoutExtent - layoutExtentOffsetCompensation
);
layoutExtentOffsetCompensation = layoutExtent;
}
bool active = constraints.overlap <0.0 || layoutExtent> 0.0;
float overscrolledExtent =
constraints.overlap < 0.0f ? constraints.overlap.abs() : 0.0f;
child.layout(
constraints.asBoxConstraints(
maxExtent: layoutExtent + overscrolledExtent
),
parentUsesSize: true
);
if (active)
{
geometry = new SliverGeometry(
scrollExtent: layoutExtent,
paintOrigin: -overscrolledExtent - constraints.scrollOffset,
paintExtent: Mathf.Max(
Mathf.Max(child.size.height, layoutExtent) - constraints.scrollOffset, 0.0f),
maxPaintExtent: Mathf.Max(
Mathf.Max(child.size.height, layoutExtent) - constraints.scrollOffset, 0.0f),
layoutExtent: Mathf.Max(layoutExtent - constraints.scrollOffset, 0.0f));
}
else
{
geometry = SliverGeometry.zero;
}
}
void _resolve()
{
if (_resolvedPadding != null && _lastResolvedConstraints == constraints)
{
return;
}
float paddingValue = constraints.viewportMainAxisExtent * viewportFraction;
_lastResolvedConstraints = constraints;
switch (constraints.axis)
{
case Axis.horizontal:
_resolvedPadding = EdgeInsets.symmetric(horizontal: paddingValue);
break;
case Axis.vertical:
_resolvedPadding = EdgeInsets.symmetric(vertical: paddingValue);
break;
}
}
public abstract SliverGridLayout getLayout(SliverConstraints constraints);
