private void RemoveInsertionAdorner()
 {
     if (_insertionAdorner != null)
     {
         _insertionAdorner.Detach();
         _insertionAdorner = null;
     }
 }
 private void CreateInsertionAdorner()
 {
     if (_targetItemContainer != null)
     {
         // Here, I need to get adorner layer from targetItemContainer and not targetItemsControl.
         // This way I get the AdornerLayer within ScrollContentPresenter, and not the one under AdornerDecorator (Snoop is awesome).
         // If I used targetItemsControl, the adorner would hang out of ItemsControl when there's a horizontal scroll bar.
         var adornerLayer = AdornerLayer.GetAdornerLayer(_targetItemContainer);
         _insertionAdorner = new InsertionAdorner(_hasVerticalOrientation, _isInFirstHalf, _targetItemContainer, adornerLayer);
     }
 }