internal virtual void SetFirst(Vector scrollPos)
{
FirstInCache = VirtualizingAverages.GetStartIndex(_templatedParent, _panelOffset - _cache.GetBackCacheSize(_tempViewport, _tempAverageItem), _items, Vert);
_firstInView = VirtualizingAverages.GetStartIndex(_templatedParent, _panelOffset, _items, Vert);
_currentOffset = VirtualizingAverages.GetOffsetForIndex(_templatedParent, FirstInCache, _items, Vert);
_numInView = 0;
_numInCache = 0;
NumInFullView = 0;
var av = VirtualizingAverages.GetEstimatedAverage(_templatedParent, _items, Vert);
_tempAverageItem = Vert ? av.Height : av.Width;
}
internal override void SetFirst(Vector scrollPos)
{
_firstInView = (int)(Vert ? scrollPos.Y : scrollPos.X);
if (_items is IGroupingView gv)
{
_firstInView = gv.GetLocalItemPosition(_firstInView);
}
ScrollOffset = (int)(Vert ? scrollPos.Y : scrollPos.X) - _firstInView;
_currentOffset = VirtualizingAverages.GetOffsetForIndex(_templatedParent, _firstInView, _items, Vert);
FirstInCache = VirtualizingAverages.GetStartIndex(_templatedParent, _currentOffset - _cache.GetBackCacheSize(_tempViewport, _tempAverageItem), _items, Vert);
_currentOffset = VirtualizingAverages.GetOffsetForIndex(_templatedParent, FirstInCache, _items, Vert);
_numInView = 0;
_numInCache = 0;
NumInFullView = 0;
var av = VirtualizingAverages.GetEstimatedAverage(_templatedParent, _items, Vert);
_tempAverageItem = Vert ? av.Height : av.Width;
}