private function moveComplete():void
{
    topLevelContainer.dispatchEvent(new MouseEvent(MouseEvent.MOUSEMOUSE, true, false, topLevelContainer.mouseX, topLevelContainer.mouseY);
}

_bounds = getBounds(this);

if (isMouseOver()) doOver(true);

private function isMouseOver():Boolean {
    //trace ("isMouseOver:");
    var xBool:Boolean = _bounds.left < mouseX && mouseX < _bounds.right;
    var yBool:Boolean = _bounds.top < mouseY && mouseY < _bounds.bottom;
    //trace (" - xBool: " + xBool);
    //trace (" - yBool: " + yBool);
    return xBool && yBool;
}

myBtn.addEventListener(MouseEvent.MOUSE_OVER, btnOverHandler);

function btnOverHandler(e:MouseEvent = null):void{
trace('do stuff on roll over!');
}

//then you can do this wherever you need
btnOverHandler();

function isMouseOver(target:DisplayObject,container:DisplayObjectContainer):Boolean{
   var isOver:Boolean = false;
   var pt:Point = new Point(mouseX, mouseY);
   var objects:Array = container.getObjectsUnderPoint(pt);
   for(var i:int = 0 ; i < objects.length; i++){
      if(objects[i] == target) {
         isOver = true;
         break;
      }
   }
   return isOver;
}

slidingUI.mousenabled = false
slidingUI.mousechildren = false