Swift 4 Mapview не вызывает метод делегата f

Я пытаюсь представить контроллер представления, когда пользователь касается врага в 50 метрах от моего местоположения с помощью учебника из (https://www.raywenderlich.com/151817/how-to-make-an-app-like-pokemon-go). Но мой viewcontroller не отображается, и я думаю, что не вызываю свой метод делегата из расширения. Как мне это исправить? Это мой код:

import UIKit
import MapKit
class GoogleMapsViewController: UIViewController, CLLocationManagerDelegate {
    var targets = [Item]()
    var locationManager: CLLocationManager!
    var userLocation: CLLocation?
    @IBOutlet weak var mapView: MKMapView!

    override func viewDidLoad() {
        super.viewDidLoad()
        mapView.showsUserLocation = true
        mapView.mapType = MKMapType(rawValue: 0)!
        mapView.userTrackingMode = MKUserTrackingMode(rawValue: 2)!
        setupLocations()        // Do any additional setup after loading the view.
        locationManager = CLLocationManager()
        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyBest

        // Check for Location Services

        if CLLocationManager.locationServicesEnabled() {
            locationManager.requestWhenInUseAuthorization()
            locationManager.startUpdatingLocation()
            locationManager.startUpdatingHeading()

        }

    } 

    func setupLocations() {
        let pdpk = Item( Place : "Pildammsparken", location: CLLocation(latitude: 55.590105, longitude:  12.988737))
        targets.append(pdpk)
        let btp = Item( Place : "Bulltoftaparken", location: CLLocation(latitude: 55.601326, longitude:  13.079005))
        targets.append(btp) for item in targets {
            let annotation = MapA(location: item.location.coordinate, item: item)
            self.mapView.addAnnotation(annotation)

        }
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        defer { userLocation = locations.last }

        if userLocation == nil {
            // Zoom to user location
            if let uLocation = locations.last {
                let viewRegion = MKCoordinateRegionMakeWithDistance(uLocation.coordinate, 2000, 2000)
                mapView.setRegion(viewRegion, animated: false)
                print(uLocation)

            }

        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

extension GoogleMapsViewController: MKMapViewDelegate {
    func mapView(_ mapView: MKMapView, didUpdate userLocation: MKUserLocation) {
        self.userLocation = userLocation.location
    }

    func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
        //1
        let coordinate = view.annotation!.coordinate
        //2
        if let userCoordinate = userLocation {
            //3
            if userCoordinate.distance(from: CLLocation(latitude: coordinate.latitude, longitude: coordinate.longitude)) < 50 {
                //4
                print("test")
                let storyboard = UIStoryboard(name: "Main", bundle: nil)

                if let viewController = storyboard.instantiateViewController(withIdentifier: "ARViewController") as?    PlaceViewController {
                    // more code later
                    //5
                    if let mapAnnotation = view.annotation as? MapA {
                        //6
                        self.present(viewController, animated: true, completion: nil)
                    }
                }
            }
        }
    }
}