 {
 	import flash.events.Event;
 	
+	import mx.collections.ICollectionView;
 	import mx.collections.IList;
+	import mx.collections.IViewCursor;
 	import mx.controls.Tree;
 	import mx.core.ScrollPolicy;
 	import mx.core.mx_internal;

			super.configureScrollBars();
			
			runningDataEffect = rda;
		}
		
		override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number):void

		 */
		override protected function configureScrollBars():void
		{
			var ac:ICollectionView = actualCollection;
			var ai:IViewCursor = actualIterator;
			var rda:Boolean = runningDataEffect;
			
			runningDataEffect = true;
			actualCollection = ac || collection; // avoids null pointer error
			actualIterator = ai || iterator;
			
			// This is not a perfect scrolling solution.  It looks ok when there is a partial row showing at the bottom.
			var mvsp:int = Math.max(0, collection.length - listItems.length + 1);
