public void RemoveItem(VListItemBase itemToBeRemoved)
{
itemToBeRemoved.IsVLoaded = false;
_virtItems.Remove(itemToBeRemoved);
_loadedSegment = new Segment();
RearrangeAllItems();
PerformLoadUnload(true);
}
public void InsertRemoveItems(int index, List <VListItemBase> itemsToInsert, bool keepItemsBelowIndexFixed = false, VListItemBase itemToRemove = null)
{
bool needToAdjustScrollPositionAfterInsertion = false;
if (keepItemsBelowIndexFixed)
{
double totalHeightOfAllItemsBeforeIndex = 0;
for (int i = 0; i < index; i++)
{
totalHeightOfAllItemsBeforeIndex += VirtItems[i].FixedHeight + VirtItems[i].Margin.Top + VirtItems[i].Margin.Bottom;
}
if (totalHeightOfAllItemsBeforeIndex < _scrollViewer.VerticalOffset + _scrollViewer.ViewportHeight)
{
needToAdjustScrollPositionAfterInsertion = true;
}
}
// UnloadItemsInSegment(_loadedSegment);
_loadedSegment = new Segment();
var totalHeight = itemsToInsert.Sum(i => i.FixedHeight + i.Margin.Top + i.Margin.Bottom);
_virtItems.InsertRange(index, itemsToInsert);
if (itemToRemove != null)
{
itemToRemove.IsVLoaded = false;
totalHeight -= itemToRemove.FixedHeight + itemToRemove.Margin.Top + itemToRemove.Margin.Bottom;
_virtItems.Remove(itemToRemove);
}
RearrangeAllItems();
if (needToAdjustScrollPositionAfterInsertion)
{
_changingVerticalOffset = true;
//Debug.WriteLine("SCROLLING TO " + _scrollViewer.VerticalOffset + totalHeight + " scroll height : " + _scrollViewer.ExtentHeight);
_scrollViewer.ScrollToVerticalOffset(_scrollViewer.VerticalOffset + totalHeight);
_changingVerticalOffset = false;
}
PerformLoadUnload(false);
}
