Help with comboBox

1

hi everyone

I use comboBox make a links.the code like this:

stop();
import mx.controls.ComboBox;
import mx.transitions.Tween;
import mx.transitions.easing.*;
Stage.scaleMode = "noscale";
createClassObject(ComboBox,"my_combo",this.getNextHighestDepth(),{_x:90,_y:30});
my_combo.setSize(200);
my_combo.setStyle("openEasing",Elastic.easeOut);
my_combo.setStyle("openDuration",800);
//loadxml
myXML = new XML();
myXML.ignoreWhite = true;
myXML.load("http://www.webstudio.com.cn/wsswf/c...nks/example.xml");
myXML.onLoad =function(success){
// --
if(success){
 links = new Array();
 // --
 for (var i = 0; i<myXML.firstChild.childNodes.length; i++) {
   links.addItem({label:myXML.firstChild.childNodes*.childNodes, data:myXML.firstChild.childNodes*.attributes.url});
  }
}else{
 trace("cannot load xml");
}
   
 // --
 //add listenerobject
 listenerObject = new Object();
 listenerObject.change = function(event) {
  //
  //getURL(links[my_combo.selectedIndex].data,"_blank");
  getURL(event.target.getValue(),"_blank");
  trace(event.target.getValue());
 };
 // --
 my_combo.addEventListener("change", listenerObject);
 my_combo.dataProvider = links;
}

the demo is here:
http://www.webstudio.com.cn/wsswf/combolinks/combxml.swf
the xml file is here:
http://www.webstudio.com.cn/wsswf/combolinks/example.xml

but why the first link is not work?and when you first click another links then click the first link ,It is work why?

thanks a lot.