      *  @see lastIndexInView
      *  @see horizontalScrollPosition
      */
-    override public function horizontalScrollPositionDelta(unit:uint):Number
+    override public function getHorizontalScrollPositionDelta(unit:ScrollUnit):Number
     {
         var g:GroupBase = target;
         if (!g)

        var itemR:Rectangle = null;
        switch(unit)
        {
            case Keyboard.LEFT:
            case Keyboard.PAGE_UP:
                itemR = findLayoutItemBounds(g, firstIndexInView, -1, scrollR);
                break;

            case Keyboard.RIGHT:
            case Keyboard.PAGE_DOWN:
                itemR = findLayoutItemBounds(g, lastIndexInView, +1, scrollR);
                break;

            default:
                return super.horizontalScrollPositionDelta(unit);
        }
        
        if (!itemR)

        setColumnCount(visibleColumns);  
        setIndexInView(firstColInView, lastColInView);
        layoutTarget.setContentSize(maxX, maxY);      	      
    }


