xmlns:mx="library://ns.adobe.com/flex/mx">
import mx.controls.Alert;
import mx.events.CloseEvent;
// Define variable to hold the Alert object.
public var myAlert:Alert;
private function openAlert():void {
myAlert = Alert.show("Copy Text?", "Alert",Alert.OK | Alert.CANCEL);
// Set the height and width of the Alert control.
myAlert.height=250;
myAlert.width=250;
}