add object in the list

iam not realy sure if i can understand you , but how can i fix it

listbox1.addItem (...)

here is the full code

package {
import flash.display.MovieClip;
   import flash.events.MouseEvent
   import flash.events.Event;

public class MAIN  extends MovieClip {
  var additemsvar:String
  var addpricevar:int
  var removeitemvar:int
  var itemsnp:Array = new Array (100)
  var itemsinfo:Object = new Object()
  var za:int = 0
  var da:Array = new Array (100)
  public function MAIN () {
    addbutton.addEventListener(MouseEvent.CLICK ,addbutton1)
    removebutton.addEventListener(MouseEvent.CLICK ,removebutton1)
    addEventListener(Event.ENTER_FRAME , onEnterFrame)
  addEventListener(Event.ADDED_TO_STAGE,ADDED_TO_STAGE)
  }
  public function ADDED_TO_STAGE (event:Event){
  
   itemsinfo.name1 = new Array()
   itemsinfo.price1 = new Array()
  
  }
  public function onEnterFrame (event:Event){
  
   if(listbox1.selectedIndex != -1){
   itemname11.text = String({label:listbox1.getItemAt(listbox1.selectedIndex)})
   }
  
  
  }
 
 
  public function addbutton1 (event:MouseEvent){
  
   additemsvar = additems.text
   addpricevar = int (addprice.text)
  
   listbox1.addItem ({label:String(itemsinfo.name1[za])})
   listbox2.addItem ({label:itemsnp[za]})
   itemsinfo.name1.push (additemsvar)
   itemsinfo.price1.push (addpricevar)
   za += 1
   trace (itemsinfo.name1)
   for (var z:String in itemsinfo){
    trace (z + ":" + itemsinfo)
   }
  
   }
  public function removebutton1 (event:MouseEvent){
  
   trace (listbox1.selectedIndex)
  
   listbox1.removeItemAt(listbox1.selectedIndex)
  
  }
  function traceItemsnpF(a:Array):void{

for(var i:int=0;i<a.length;i++){

for(var s:String in a){

trace(s,a+":"+a);

}

}

}

 
}
}

thank you for the replay