private void UnrealizeItems()
{
var window = GetRealizationWindow();
foreach (var item in MainPanel.Children)
{
var itemTop = Canvas.GetTop(item);
if (itemTop < window.Top || itemTop > window.Bottom)
{
MainPanel.Children.Remove(item);
GalleryThumbnailTemplate container = item as GalleryThumbnailTemplate;
(container.Tag as LayoutInfo).IsRendered = false;
containerCache.Put(container);
}
}
}