这个警告告诉你不应该调用CLLocationManager.locationServicesEnabled()，因为这会花费很长时间并导致UI出现问题。相反，你应该实现委托函数locationManagerDidChangeAuthorization(_:)，检查authorizationStatus并将结果存储在某个地方，然后在if中使用存储的值。

请尝试使用位置管理器更改授权：

class Prova: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {

let mapView = MKMapView()
let manager = CLLocationManager()

override func viewDidLoad() {
    super.viewDidLoad()
    mapView.translatesAutoresizingMaskIntoConstraints = false
    view.addSubview(mapView)
    mapView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
    mapView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
    mapView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
    mapView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
    
    locationAuthorization()
}

func locationAuthorization(){
    switch manager.authorizationStatus {
    case .authorizedWhenInUse:
        print("Authorized")
        determineMyCurrentLocation()
    case .denied:
       break
    case .authorizedAlways:
        determineMyCurrentLocation()
    case.notDetermined:
        manager.requestAlwaysAuthorization()
        manager.requestWhenInUseAuthorization()
        sleep(2)
        locationAuthorization()
    default:
        break
    }
}

func determineMyCurrentLocation() {
    print("determine current location")
    if CLLocationManager.locationServicesEnabled() {
        DispatchQueue.main.async {
            self.manager.delegate = self
            self.manager.desiredAccuracy = kCLLocationAccuracyBest
            self.manager.startUpdatingLocation()
            self.mapView.delegate = self
            self.mapView.mapType = .standard
            self.mapView.isZoomEnabled = true
            self.mapView.isScrollEnabled = true
            self.mapView.showsUserLocation = false // if you want to show default pin
        }
    }
    
    if let coor = mapView.userLocation.location?.coordinate {
        mapView.setCenter(coor, animated: true)
    }
}

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
}

func locationManager(_ manager: CLLocationManager, didUpdateLocations
    locations: [CLLocation]) {
    
    guard let mylocation = manager.location else { return }
    
    let myCoordinates: CLLocationCoordinate2D = mylocation.coordinate

    mapView.mapType = MKMapType.standard

    let span = MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1)
    let region = MKCoordinateRegion(center: myCoordinates, span: span)
    mapView.setRegion(region, animated: true)
    
    let pin = MKPointAnnotation()
    pin.coordinate = myCoordinates
    pin.title = "You are here"
    mapView.addAnnotation(pin)
 }
}