HERES WHAT IM DOING
import ContentReader;
import flash.events.Event;

var theReader = new ContentReader("content.xml");
//wait till it's done loading
theReader.addEventListener(Event.COMPLETE, traceOut, false, 0, true);

function traceOut($evt:Event):void{

trace(theReader.getNumberOfPages());
}



HERES THE CLASS
package{
	import flash.net.URLLoader;
	import flash.net.URLRequest;
	import flash.events.*;
	
	public class ContentReader extends URLLoader{
		private var contentFile:String;
		private var xmlFile:XML;
		private var numberOfPages:int;

		public function ContentReader(contentFile:String){
			this.contentFile = contentFile;
			load(new URLRequest(contentFile));
			this.addEventListener(Event.COMPLETE, loadCompleted);
		}
		
		public function loadCompleted(e:Event){
				e.target.getData();
				//trace(temp..item[0].title);
				//trace(numberOfPages);
				//trace(data);
		}
		
		public function getData(){
				var temp:XML = new XML(data);
				xmlFile = temp;
				this.numberOfPages = xmlFile..item.length();	
				//trace(data);
				trace(numberOfPages); //returns 4
		}
		
		public function getTitle(item:int):String{
			return (xmlFile..item[item].title);
		}
		
		public function getContent(item:int):String{
			return(xmlFile..item[item].text);
		}
		
		public function getNumberOfPages():int{
			return numberOfPages; //returns 0
		}
		
	}
}