private void CreateInsertionAdorner(DependencyObject draggedItem, ItemsControl itemsControl)
{
var draggedOveredContainer = itemsControl.GetItemContainer(draggedItem);
bool showInRight = false;
if (draggedOveredContainer == null)
{
draggedOveredContainer = itemsControl.GetLastContainer();
showInRight = true;
}
_insertionAdorner = new InsertionAdorner(draggedOveredContainer, showInRight);
}