check the code now:
Code:
package clases.menu{
	import flash.display.MovieClip;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import flash.display.Sprite;
	import clases.menu.submenu;
	import com.greensock.*;
	import com.greensock.easing.*;
	import com.greensock.plugins.*;

	public class menu extends MovieClip {


		private var itemArray = [];
		private var tamArray:int;
		private var i:int;
		private var n:int;
		private var j:int;
		private var newdestino:int;
		var newtarget:MovieClip;
		var oldtarget:MovieClip;
		var objetivo:MovieClip;
		

		public function menu() {
			for (n=0; n<4; n++) {
				var item:base_primaria= new base_primaria();
				addChild(item);
				item.x = 0;
				item.y = (item.height+2) * n ;
				item.buttonMode = true;
				item.name="elementomenu"+n;

				item.addEventListener(MouseEvent.CLICK,crearsub);
				//item.addEventListener(MouseEvent.ROLL_OUT,eliminarsub);
				itemArray.push(item);
				tamArray=itemArray.length;

			}
					}
		private function posicionar():void {
			
			for (i=0; i<tamArray-1; i++) {
				var elemento=itemArray[i+1];
				newdestino = (itemArray[i].y+itemArray[i].height+2);
				elemento.y=newdestino;
				//TweenLite.to(elemento, 1, {x:elemento.x, y:newdestino, ease:Elastic.easeOut});
			}
			
		}
		private function crearsub(e:MouseEvent):void {
			eliminarsub(oldtarget);
			var objeto=e.currentTarget;
			if(objeto!=oldtarget){
			var subcontenedor:Sprite= new Sprite();
			var misubmenu:submenu = new submenu();
			subcontenedor.addChild(misubmenu);
			objeto.addChild(subcontenedor);
			misubmenu.alpha=0.5;
			misubmenu.y=26;
			misubmenu.x=20;
			TweenLite.to(misubmenu,0.8,{alpha:1});
			oldtarget=objeto;
			}
			posicionar();
		}
		private function eliminarsub(objetivo:MovieClip):void {
			if(objetivo!=null){
				objetivo.removeChildAt(1);
						}
			trace(objetivo);
			oldtarget=newtarget;
			posicionar();
		}
	}
}
Check the SWF


Problems:
- How to avoid repeat the method to create submenu when it is already created in the element clicked.
- How to avoid the elements from submenu fire the method create submenu.
target/currentTarget/mouseChild=false... anything else.
- Why relocate method doesn't work with TweenLite?

Thanks
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