code: function () {
  
  		// The Menu is below the context element
  		if ((oMenu.cfg.getProperty(_Y) - scrollY) > nContextElY) {
  			return (nBottomRegionHeight - nViewportOffset);				
  		}
  		else {	// The Menu is above the context element
  			return (nTopRegionHeight - nViewportOffset);				
  		}
  
  	}
docs: /*
  Uses the context element's position to calculate the availble height
  above and below it to display its corresponding Menu.