ios - Mapkit 在 swift 中覆盖问题

Question

我在 map 上的 long:39 和 lat:77 位置显示透明圆圈时遇到问题。我还必须一次显示多个圆圈。我是使用 mapkit 的新手，所以要基本。我在这里先向您的帮助表示感谢。

class FirstViewController: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate
{

@IBOutlet weak var mapView: MKMapView!

let locationManager = CLLocationManager()

override func viewDidLoad()
{
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    self.locationManager.delegate = self
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
    self.locationManager.requestAlwaysAuthorization()
    self.locationManager.startUpdatingLocation()
    self.mapView.showsUserLocation = true

}
override func didReceiveMemoryWarning()
{
    super.didReceiveMemoryWarning()
}
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation])
{
    let location = locations.last
    let center = CLLocationCoordinate2D(latitude: location!.coordinate.latitude, longitude: location!.coordinate.longitude)
    let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 1, longitudeDelta: 1))
    self.mapView.setRegion(region, animated: true)
    self.locationManager.stopUpdatingLocation()//
}
func locationManager(manager: CLLocationManager, didFailWithError error: NSError)
{
    print("Errors: " + error.localizedDescription)
}

}

Answer 1

class FirstViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        self.locationManager.delegate = self
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
        self.locationManager.requestAlwaysAuthorization()
        self.locationManager.startUpdatingLocation()
        self.mapView.showsUserLocation = true

    }

    func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation])
    {
        let location = locations.last
        let center = CLLocationCoordinate2D(latitude: location!.coordinate.latitude, longitude: location!.coordinate.longitude)
        let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 1, longitudeDelta: 1))
        self.mapView.setRegion(region, animated: true)
        self.locationManager.stopUpdatingLocation()
        // Provide a radius in meters
        showCircle(center, radius: <#CLLocationDistance#>)
    }

    // Radius is measured in meters
    func showCircle(coordinate: CLLocationCoordinate2D, radius: CLLocationDistance) {
        let circle = MKCircle(centerCoordinate: coordinate, radius: radius)
        mapView.addOverlay(circle)
    }

}

extension FirstViewController: MKMapViewDelegate {
    func mapView(mapView: MKMapView, rendererForOverlay overlay: MKOverlay) -> MKOverlayRenderer {
        let circleRenderer = MKCircleRenderer(overlay: circleOverlay)
        circleRenderer.fillColor = UIColor.blackColor()
        circleRenderer.alpha = 0.1

        return circleRenderer
    }
}