internal override bool PositionTopRealizedItem(ref double visibleItemsTop)
{
RadVirtualizingDataControlItem firstRealizedItem = this.owner.firstItemCache;
WrapRow firstWrapRow = null;
int wrapRowsCount = this.wrapRows.Count;
if (wrapRowsCount > 0)
{
firstWrapRow = this.wrapRows[0];
}
bool isEnoughSpaceForItemInRow = this.CheckEnoughSpaceForItemInRow(firstWrapRow, firstRealizedItem, false);
if (firstWrapRow == null || !isEnoughSpaceForItemInRow)
{
if (!isEnoughSpaceForItemInRow)
{
visibleItemsTop -= firstWrapRow.rowLength;
this.OnRowFilled(firstWrapRow, false);
if (!this.CanRealizeTop(visibleItemsTop))
{
return(false);
}
}
firstWrapRow = this.InsertWrapRowAt(0);
firstWrapRow.lastItem = firstRealizedItem;
firstWrapRow.rowLength = this.GetItemLength(firstRealizedItem);
firstWrapRow.rowOffset = firstWrapRow.next != null ? firstWrapRow.next.rowOffset - firstWrapRow.rowLength : 0;
}
double currentRowLength = firstWrapRow.rowLength;
double difference = 0;
switch (this.orientationCache)
{
case Orientation.Horizontal:
difference = firstRealizedItem.height - currentRowLength;
if (currentRowLength < firstRealizedItem.height)
{
firstWrapRow.rowLength = firstRealizedItem.height;
visibleItemsTop -= difference;
firstWrapRow.rowOffset -= difference;
}
firstRealizedItem.SetVerticalOffset(firstWrapRow.rowOffset);
if (firstWrapRow.firstItem == null)
{
firstRealizedItem.SetHorizontalOffset(this.owner.availableWidth - firstRealizedItem.width);
}
else
{
firstRealizedItem.SetHorizontalOffset(firstWrapRow.firstItem.horizontalOffsetCache - firstRealizedItem.width);
if (difference != 0)
{
this.SynchItemOffsetInRow(firstWrapRow);
}
}
break;
case Orientation.Vertical:
difference = firstRealizedItem.width - currentRowLength;
if (currentRowLength < firstRealizedItem.width)
{
firstWrapRow.rowLength = firstRealizedItem.width;
visibleItemsTop -= difference;
firstWrapRow.rowOffset -= difference;
}
firstRealizedItem.SetHorizontalOffset(firstWrapRow.rowOffset);
if (firstWrapRow.firstItem == null)
{
firstRealizedItem.SetVerticalOffset(this.owner.availableHeight - firstRealizedItem.height);
}
else
{
firstRealizedItem.SetVerticalOffset(firstWrapRow.firstItem.verticalOffsetCache - firstRealizedItem.height);
if (difference != 0)
{
this.SynchItemOffsetInRow(firstWrapRow);
}
}
break;
}
firstWrapRow.firstItem = firstRealizedItem;
firstRealizedItem.wrapRow = firstWrapRow;
if (this.owner.IsFirstItemFirstInListSource())
{
this.OnRowFilled(firstWrapRow, false);
}
return(true);
}
internal override void OnContainerSizeChanged(RadVirtualizingDataControlItem container, Size newSize, Size oldSize)
{
base.OnContainerSizeChanged(container, newSize, oldSize);
if (!this.topRealized.Contains(container))
{
RadVirtualizingDataControlItem pivotContainer = container.next;
int containersToSkip = 0;
if (pivotContainer != null)
{
containersToSkip = Math.Max(this.stackCount - this.owner.realizedItems.IndexOf(pivotContainer), 0);
}
while (pivotContainer != null)
{
if (containersToSkip > 0)
{
containersToSkip--;
continue;
}
this.slotsRepository.Remove(pivotContainer.associatedDataItem.GetHashCode());
pivotContainer = pivotContainer.next;
}
this.ReorderViewportOnItemsChanged();
}
else
{
double newOffset = 0;
double offsetDelta = 0;
switch (this.orientationCache)
{
case Orientation.Horizontal:
offsetDelta = newSize.Height - oldSize.Height;
newOffset = container.verticalOffsetCache - offsetDelta;
container.SetVerticalOffset(newOffset);
double horizontalOffset = container.horizontalOffsetCache;
while (container.previous != null)
{
container = container.previous;
if (container.horizontalOffsetCache == horizontalOffset)
{
container.SetVerticalOffset(container.verticalOffsetCache - offsetDelta);
}
}
break;
case Orientation.Vertical:
offsetDelta = newSize.Width - oldSize.Width;
newOffset = container.horizontalOffsetCache - offsetDelta;
container.SetHorizontalOffset(newOffset);
double verticalOffset = container.verticalOffsetCache;
while (container.previous != null)
{
container = container.previous;
if (container.verticalOffsetCache == verticalOffset)
{
container.SetHorizontalOffset(container.horizontalOffsetCache - offsetDelta);
}
}
break;
}
}
// Extend the length with the new diff, although the extension could be less
var prevLength = this.Orientation == Windows.UI.Xaml.Controls.Orientation.Horizontal ? oldSize.Height : oldSize.Width;
var sizeChange = this.GetItemLength(container) - prevLength;
this.CorrectScrollableContentSize(sizeChange);
this.EnsureCorrectLayout();
this.CheckBottomScrollableBounds();
}
internal override bool PositionBottomRealizedItem(RadVirtualizingDataControlItem item, ref double visibleItemsBottom)
{
RadVirtualizingDataControlItem realizedItem = item;
double itemLength = this.GetItemLength(realizedItem);
WrapRow lastWrapRow = null;
int wrapRowsCount = this.wrapRows.Count;
if (wrapRowsCount > 0)
{
lastWrapRow = this.wrapRows[wrapRowsCount - 1];
}
bool isEnoughSpaceForItemInRow = true;
if (lastWrapRow != null)
{
isEnoughSpaceForItemInRow = this.CheckEnoughSpaceForItemInRow(lastWrapRow, realizedItem, true);
}
if (lastWrapRow == null || !isEnoughSpaceForItemInRow)
{
if (!isEnoughSpaceForItemInRow)
{
visibleItemsBottom += lastWrapRow.rowLength;
this.OnRowFilled(lastWrapRow, true);
if (!this.CanRealizeBottom(visibleItemsBottom))
{
return(false);
}
}
lastWrapRow = this.InsertWrapRowAt(wrapRowsCount);
lastWrapRow.firstItem = realizedItem;
if (lastWrapRow.previous == null)
{
double defaultPosition = 0;
if (this.owner.scrollScheduled)
{
defaultPosition = this.ScrollOffset;
}
lastWrapRow.rowOffset = this.averageItemLength > 0 ? item.AssociatedDataItem.Index / this.averageItemCountPerRow * this.averageItemLength : defaultPosition;
}
else
{
lastWrapRow.rowOffset = lastWrapRow.previous.rowOffset + lastWrapRow.previous.rowLength;
}
lastWrapRow.rowLength = itemLength;
}
double currentRowLength = lastWrapRow.rowLength;
switch (this.orientationCache)
{
case Orientation.Horizontal:
if (currentRowLength < realizedItem.height)
{
lastWrapRow.rowLength = realizedItem.height;
visibleItemsBottom += realizedItem.height - currentRowLength;
}
realizedItem.SetVerticalOffset(lastWrapRow.rowOffset);
if (lastWrapRow.lastItem == null)
{
realizedItem.SetHorizontalOffset(0);
}
else
{
realizedItem.SetHorizontalOffset(lastWrapRow.lastItem.horizontalOffsetCache + lastWrapRow.lastItem.width);
}
break;
case Orientation.Vertical:
if (currentRowLength < realizedItem.width)
{
lastWrapRow.rowLength = realizedItem.width;
visibleItemsBottom += realizedItem.width - currentRowLength;
}
realizedItem.SetHorizontalOffset(lastWrapRow.rowOffset);
if (lastWrapRow.lastItem == null)
{
realizedItem.SetVerticalOffset(0);
}
else
{
realizedItem.SetVerticalOffset(lastWrapRow.lastItem.verticalOffsetCache + lastWrapRow.lastItem.height);
}
break;
}
lastWrapRow.lastItem = realizedItem;
realizedItem.wrapRow = lastWrapRow;
if (this.owner.IsLastItemLastInListSource())
{
this.OnRowFilled(lastWrapRow, true);
}
return(true);
}
