 import spark.components.supportClasses.ButtonBase;
 import spark.components.supportClasses.DropDownController;
 import spark.components.supportClasses.ListBase;
+import spark.core.NavigationUnit;
 import spark.events.DropDownEvent;
 import spark.layouts.VerticalLayout;
 import spark.layouts.supportClasses.LayoutBase;

    private var labelChanged:Boolean = false;
    // TODO (jszeto) Should this be protected?
    private var proposedSelectedIndex:Number = -1;
	
	//--------------------------------------------------------------------------
    //

        
        if (!dropDownController.processKeyDown(event))
        {
        	var navigationUnit:uint;
        	var proposedNewIndex:int = -1;
        	
			if (dropDownController.isOpen)
			{	
	        	navigationUnit = mapEventToNavigationUnit(event);
	        	proposedNewIndex = layout.getDestinationIndex(navigationUnit, proposedSelectedIndex)
	        	
	        	if (proposedNewIndex != -1)
	        	{
