package util
{
	import mx.controls.listClasses.ListBase;
	import mx.core.IDataRenderer;
	import mx.core.mx_internal;
	
	use namespace mx_internal;
	
	/**
	 * Clean up utility class
	 *  
	 */
	public class CleanUp {
		
		/**
		 * Helper function that cleans up a list's item renderers.
		 * 
		 * <P>The item renderers contain a data member that holds a reference to the data the list was
		 * trying to display. The list doesn't clean up the item renderers data member when the list provider is set
		 * to null. So, this reference prevents elements from being garbage collected and needs to be manually cleaned up</P>.
		 *  
		 * @param list The list for wich the Item Renderers need to be cleaned up.
		 * 
		 */
		public static function cleanItemRenderersData(list:ListBase):void {
			var renderers:Array = list.rendererArray;	// two dimensional array
			var renderer:IDataRenderer = null;
			for (var row:int = 0 ; row < renderers.length ; row++) {
				for (var col:int = 0 ; col < renderers[row].length ; col ++) {
					renderer = renderers[row][col] as IDataRenderer;
					if (renderer) renderer.data = null;
				}
			}
		}		
	}
}