gistfile1.swift

func mapViewDidLoad(mapView:AGSMapView!){
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "responseToEventChanged:", name: AGSMapViewDidEndZoomingNotification, object: nil)
}
    
func responseToEventChanged(notification: NSNotification){
    let theString = "xmin = \(mapView.visibleAreaEnvelope.xmin),\nymin = \(mapView.visibleAreaEnvelope.ymin),\nxmax = \(mapView.visibleAreaEnvelope.xmax),\nymax = \(mapView.visibleAreaEnvelope.ymax)"
    println(theString);
}