无法创建自定义MKAnnotationView

Question

我很难显示自定义注释视图。具体来说，我试图设置一个名为“pin”的图像作为新的地图引脚。默认引脚总是显示。我已经做了几个小时的小改动，例如将“pin”改为“pin.png”，并改变了方法的结构。这是我的。你可以看看有什么突出的东西吗？

感谢您的帮助！

注释类：

class Annotation: NSObject, MKAnnotation { 
    dynamic var coordinate : CLLocationCoordinate2D 
    var title: String? 
    var subtitle: String? 

    init(location coord:CLLocationCoordinate2D) { 
     self.coordinate = coord 
     super.init() 
    } 

    required init?(coder aDecoder: NSCoder) { 
     fatalError("init(coder:) has not been implemented") 
    } 
} 

AnnotationView类：

class AnnotationView : MKAnnotationView { 
    override init(annotation:MKAnnotation?, reuseIdentifier: String?) { 
     super.init(annotation: annotation, 
       reuseIdentifier: reuseIdentifier) 
     let im = UIImage(named: "pin")! 
     self.frame = CGRect(x: 0, y: 0, width: im.size.width/3.0 + 5, height: im.size.height/3.0 + 5) 
     self.centerOffset = CGPoint(x: 0, y: -20) 
     self.isOpaque = false 
    } 
    required init (coder: NSCoder) { 
     fatalError("NSCoding not supported") 
    } 
    override func draw(_ rect: CGRect) { 
     let im = UIImage(named: "pin")! 
     im.draw(in: self.bounds.insetBy(dx: 5, dy: 5)) 
    } 
} 

的MapView：viewFor：方法：

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? { 
    var v : MKAnnotationView! = nil 
    let ident = "pin" 
    v = mapView.dequeueReusableAnnotationView(withIdentifier: ident) 
    if v == nil { 
     v = AnnotationView(annotation: annotation, reuseIdentifier: ident) 
     v.canShowCallout = true 
    } 
    v.annotation = annotation 
    return v 
} 

其他相关方法：

@IBAction func submitDog(_ sender: Any) { 
    let newDog = Dog(name: newDogName.text!, score: 11, picture: image!, location: location!) 
    dogs.append(newDog) 
    print(dogs.last!) 
    UIView.animate(withDuration: 0.5, animations: { 

    }) { _ in 
     self.newDogView.animation = "slideUp" 
     self.newDogView.animate() 
     self.newDogView.isHidden = true 
     self.newDogName.text = "" 
     self.map.isUserInteractionEnabled = true 
    } 
    dropNewPin(locatedAt: dogs.last!.location, name: dogs.last!.name, rate: dogs.last!.score) 
} 

func dropNewPin(locatedAt: CLLocation, name: String, rate: Int) { 
    let annotation = Annotation(location: CLLocationCoordinate2D(latitude: locatedAt.coordinate.latitude, longitude: locatedAt.coordinate.longitude)) 
    annotation.title = name 
    annotation.subtitle = "\(rate)/10" 
    self.map.addAnnotation(annotation) 
} 

Answer 1

首先，你需要添加你的viewController作为地图

self.mapView.delegate = self 

的委托后，我建议你使用MKAnnotationView，而不是修改和自定义绘图添加图像，如果你需要一个定制的注解视图，那么你需要添加xib文件和您的自定义类作为文件所有者并进行适当的调整

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? { 
    //to avoid make a custom Annotation view for your user location 
    if(annotation is MKUserLocation){ 
     return nil 
    } 

    let ident = "pin" 
    var v = mapView.dequeueReusableAnnotationView(withIdentifier: ident) 
    if v == nil { 
     v = MKAnnotationView(annotation: annotation, reuseIdentifier: ident) 
     v?.image = UIImage(named: "pin") 
     v?.canShowCallout = true 
    } 
    v?.annotation = annotation 
    return v 
}