用户位置（蓝点）不断变成红色图钉

Posted 2023-03-17

【中文标题】用户位置（蓝点）不断变成红色图钉

【英文标题】：Users location (blue dot) keeps turning into red pin

【发布时间】：2016-07-28 11:46:39

【问题描述】：

我希望将用户位置显示为蓝点，同时在地图视图上也有图钉。我希望引脚有一个带有信息按钮的注释。 我可以获得用户位置的蓝点，并使引脚具有注释，例如标题和副标题。但是，当我将信息按钮添加到红色引脚时，用户位置（蓝点）会变成红色引脚。

我似乎无法发现我哪里出错了。它与最后一个函数有关，因为这是将信息按钮放在注释上的函数。但它也选择了用户当前的位置，并出于某种原因将其变成了一个 pin :(

 class GetToTheStart: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate 

@IBOutlet weak var mapView: MKMapView!




let myLocMgr = CLLocationManager()


    override func viewDidLoad() 
    super.viewDidLoad()


    myLocMgr.desiredAccuracy = kCLLocationAccuracyBest
    myLocMgr.requestWhenInUseAuthorization()
    myLocMgr.startUpdatingLocation()
    myLocMgr.delegate = self




    mapView.delegate = self


  var zoo = CLLocationCoordinate2DMake(53.3562, -6.3053)

    var zoopin = MKPointAnnotation()
    zoopin.coordinate = zoo
    zoopin.title = "dublin zoo"
    zoopin.subtitle = "hello this is the zoo"
    mapView.addAnnotation(zoopin)
    



    func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) 

    // get most recient coordinate
    let myCoor = locations[locations.count - 1]

    //get lat & long
    let myLat = myCoor.coordinate.latitude
    let myLong = myCoor.coordinate.longitude
    let myCoor2D = CLLocationCoordinate2D(latitude: myLat, longitude: myLong)

    //set span
    let myLatDelta = 0.05
    let myLongDelta = 0.05
    let mySpan = MKCoordinateSpan(latitudeDelta: myLatDelta, longitudeDelta: myLongDelta)

    let myRegion = MKCoordinateRegion(center: myCoor2D, span: mySpan)

    self.mapView.showsUserLocation = true        
    





    func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView? 
    let reuseIdentifier = "pin"
    var pin =       mapView.dequeueReusableAnnotationViewWithIdentifier(reuseIdentifier) as? MKPinAnnotationView
    if pin == nil 
        pin = MKPinAnnotationView(annotation: annotation, reuseIdentifier: reuseIdentifier)
        pin!.pinColor = .Red
        pin!.canShowCallout = true
        pin!.rightCalloutAccessoryView = UIButton(type: .DetailDisclosure)
     else 
        pin!.annotation = annotation
    
    return pin

【参考方案1】：

viewForAnnotation 委托方法将被地图上的所有注解调用，包括 userLocation。

所以你只需检查并返回 nil ，如下所示......

func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView?   
    if annotation is MKUserLocation 
    //return nil so map view draws "blue dot" for standard user location
        return nil
    
    let reuseIdentifier = "pin"
    var pin = mapView.dequeueReusableAnnotationViewWithIdentifier(reuseIdentifier) as? MKPinAnnotationView
    if pin == nil 
        pin = MKPinAnnotationView(annotation: annotation, reuseIdentifier: reuseIdentifier)
        pin!.pinColor = .Red
        pin!.canShowCallout = true
        pin!.rightCalloutAccessoryView = UIButton(type: .DetailDisclosure)
      else 
        pin!.annotation = annotation
     
     return pin

【讨论】：

很高兴...在发布问题时，至少为代码部分保持一些标准