Perchè la richiami dentro ad un metodo statico e non esiste la funzione statica dispatchEvent per EventDispatcher.
Devi creare la classe come singleton e usare il dispatchEvent sulla sua unica istanza.
Codice PHP:
package {
import flash.events.Event;
import flash.events.EventDispatcher;
public class CLASSNAME extends EventDispatcher {
private static var instance:CLASSNAME;
private static var allowInstantiation:Boolean;
public function CLASSNAME ():void {
if (!allowInstantiation) throw (new Error("Class must be instantiated with CLASSNAME.getInstance()"));
}
public static function getInstance ():CLASSNAME {
if (!instance) {
allowInstantiation = true;
instance = new CLASSNAME();
allowInstantiation = false;
}
return instance;
}
public static function caricaFile (Url:String):String {
getInstance().dispatchEvent(new Event("caricaFile"));
}
}
}