用户滚动地图时，将图钉（MKA注释）保持在中心

Question

当用户像Careem应用一样对地图进行拼写时，我想将MKAnnotaion保持在屏幕中央：

到目前为止，我设法显示了图钉，更新了图钉的位置，但是当我滚动地图时，代码中的注释最初移动了，然后又回到中心。我希望别针保持在中心。

  @IBOutlet var mapView: MKMapView!
  var centerAnnotation = MKPointAnnotation()
  var manager:CLLocationManager!

 override func viewDidLoad() {
    super.viewDidLoad()
    manager = CLLocationManager() //instantiate
    manager.delegate = self // set the delegate
    manager.desiredAccuracy = kCLLocationAccuracyBest // required accurancy

    manager.requestWhenInUseAuthorization() // request authorization
    manager.startUpdatingLocation() //update location

    var lat = manager.location.coordinate.latitude // get lat
    var long = manager.location.coordinate.longitude // get long
    var coordinate = CLLocationCoordinate2DMake(lat, long)// set coordinate

    var latDelta:CLLocationDegrees = 0.01 // set delta
    var longDelta:CLLocationDegrees = 0.01 // set long
    var span:MKCoordinateSpan = MKCoordinateSpanMake(latDelta, longDelta)
    var region:MKCoordinateRegion = MKCoordinateRegionMake(coordinate, span)

    self.mapView.setRegion(region, animated: true)
    centerAnnotation.coordinate = mapView.centerCoordinate
    self.mapView.addAnnotation(centerAnnotation)
}

func mapView(mapView: MKMapView!, regionDidChangeAnimated animated: Bool) {
    centerAnnotation.coordinate = mapView.centerCoordinate;
}

****更新****

根据安娜的建议，我已在地图上添加了视图。这里的代码：

var newPoint = self.mapView.convertCoordinate(mapView.centerCoordinate, toPointToView: self.view)



    var pinImage = UIImage(named: "yoga_pins.png")
    var imageView = UIImageView(image: pinImage) // set as you want

    imageView.image = pinImage
    imageView.backgroundColor = UIColor.clearColor()
    imageView.contentMode = UIViewContentMode.Center
    imageView.center.y = newPoint.y
    imageView.center.x = newPoint.x


    self.view.addSubview(imageView)

唯一的问题是，第一次加载地图时，位于上的注释（mapView.centerCoordinate我将使用该注释）来获取经度和纬度：

当我然后滚动地图时，图钉将移动到正确的位置（在图像下方）：

    func mapView(mapView: MKMapView!, regionDidChangeAnimated animated: Bool) {
    centerAnnotation.coordinate = mapView.centerCoordinate;

}

Answer 1

您可以使用自定义按钮。将该按钮添加到地图中心。只需根据您的情况显示和隐藏该按钮即可。因此，当您移动地图时，该按钮会保持在地图中心的同一位置。