Show Current Location and Update Location in MKMapView in Swift

You have to override CLLocationManager.didUpdateLocations (part of CLLocationManagerDelegate) to get notified when the location manager retrieves the current location:

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    if let location = locations.last{
        let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
        let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))
        self.map.setRegion(region, animated: true)
    }
}

NOTE: If your target is iOS 8 or above, you must include the NSLocationAlwaysUsageDescription or NSLocationWhenInUseUsageDescription key in your Info.plist to get the location services to work.