向具有多个自定义注释视图的地图视图添加集群注释

Question

我有一个地图视图，它有两种类型的自定义注释视图。我想知道如何为这些视图添加不同类型的集群（取决于注释视图的类型）。目前，我已经尝试按照 WWDC 2017 的 session 237 "What's new in MapKit" 中的示例项目进行所有操作。但是当我注册我的集群视图时，它什么都不做（甚至没有被调用）。我想，那是因为我使用了自定义注释视图并且没有注册它们，而是使用 MKMapViewDelegate 方法 mapView(_:viewFor:)。这是我注册自定义集群注释的代码（ClusterView 是 MKAnnotationView 的子类，我在其中定义了我的集群注释）：

 mapView.register(ClusterView.self, forAnnotationViewWithReuseIdentifier: MKMapViewDefaultClusterAnnotationViewReuseIdentifier)

上面的代码是在 viewDidLoad() 方法中定义的，但同样，它甚至没有被调用。所以，我认为我应该实施 MKMapViewDelegate 方法之一：mapView(_:clusterAnnotationForMemeberAnnotations:)。问题是，我没有任何添加集群注释的经验，所以我不知道如何正确地实现它。几个星期以来，我一直在 Internet 上寻找一些示例，但还没有找到任何东西（仅关于第三方库）。如果您知道如何实现上述方法，或将集群添加到具有不同类型的自定义注释视图（不使用第三方库）的 mapView，我将不胜感激。

Answer 1

尝试使用字符串重用标识符注册您的注释：

mapView.register(AnnotationViewMarker.self, forAnnotationViewWithReuseIdentifier: "marker")
mapView.register(AppleClusterAnnotationView.self, forAnnotationViewWithReuseIdentifier: "cluster")

我也遇到过这个问题。如果这里有一个适用于我的应用程序的示例：

override func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {        
    if annotation is MKUserLocation || annotation is UserAnnotation {
        return nil
    }

    if let marker = annotation as? WifiAnnotation {
        var view = mapView.dequeueReusableAnnotationView(withIdentifier: "marker") as? AnnotationViewMarker
        if view == nil {
            view = AnnotationViewMarker(annotation: marker, reuseIdentifier: "marker")
        }
        return view

    } else if let cluster = annotation as? MKClusterAnnotation {
        var view = mapView.dequeueReusableAnnotationView(withIdentifier: "cluster") as? AppleClusterAnnotationView
        if view == nil {
            view = AppleClusterAnnotationView(annotation: cluster, reuseIdentifier: "cluster")
        }
        return view

    }

    return nil
}

这里是我的 MKAnnotationView 的一个例子 Class:

class AppleClusterAnnotationView: MKAnnotationView {
override init(annotation: MKAnnotation?, reuseIdentifier: String?) {
    super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
    displayPriority = .defaultLow
    //collisionMode = .circle
    centerOffset = CGPoint(x: 0, y: -10) // Offset center point to animate better with marker annotations
}

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

override var annotation: MKAnnotation? {
    willSet {
        if let cluster = newValue as? MKClusterAnnotation {
            let renderer = UIGraphicsImageRenderer(size: CGSize(width: 40, height: 40))
            let count = cluster.memberAnnotations.count
            let uniCount = cluster.memberAnnotations.filter { member -> Bool in
                return (member as! WifiAnnotation).wifiType != "Ad"
                }.count
            image = renderer.image { _ in
                // Fill full circle with tricycle color
                UIColor(red: 52/255, green: 131/255, blue: 223/255, alpha: 0.22).setFill()
                UIBezierPath(ovalIn: CGRect(x: 0, y: 0, width: 40, height: 40)).fill()

                // Fill pie with unicycle color
                UIColor(red: 52/255, green: 131/255, blue: 223/255, alpha: 0.22).setFill()
                let piePath = UIBezierPath()
                piePath.addArc(withCenter: CGPoint(x: 20, y: 20), radius: 20,
                               startAngle: 0, endAngle: (CGFloat.pi * 2.0 * CGFloat(uniCount)) / CGFloat(count),
                               clockwise: true)
                piePath.addLine(to: CGPoint(x: 20, y: 20))
                piePath.close()
                piePath.fill()

                // Fill inner circle with white color
                UIColor.white.setFill()
                UIBezierPath(ovalIn: CGRect(x: 8, y: 8, width: 24, height: 24)).fill()

                // Finally draw count text vertically and horizontally centered
                let attributes = [ NSAttributedStringKey.foregroundColor: UIColor.black,
                                   NSAttributedStringKey.font: UIFont.boldSystemFont(ofSize: 15)]
                let text = "\(count)"
                let size = text.size(withAttributes: attributes)
                let rect = CGRect(x: 20 - size.width / 2, y: 20 - size.height / 2, width: size.width, height: size.height)
                text.draw(in: rect, withAttributes: attributes)

            }
        }
    }
}}

最后是我的 MKMarkerAnnotationView。有了它，您就可以进行所有设置以使其正常工作。您只需设置您的 MKAnnotation。

MKMarkerAnnotationView:

class AnnotationViewMarker: MKMarkerAnnotationView {

override open var annotation: MKAnnotation? {
    willSet {
        if let annotation = newValue as? WifiAnnotation {
            clusteringIdentifier = "WifiAnnotation"

            if annotation.wifiType == "yyy" {
                glyphImage = UIImage(named: "yyy")
                selectedGlyphImage = UIImage(named: "yyy")
                markerTintColor = UIColor("#303030")
                glyphTintColor = .white
                displayPriority = .defaultHigh
                titleVisibility = .visible
                animatesWhenAdded = true


            } else {
                glyphImage = UIImage(named: "xxx")
                selectedGlyphImage = UIImage(named: "xxx")
                markerTintColor = UIColor("#3483DF")
                glyphTintColor = .white
                displayPriority = .required
                titleVisibility = .visible
                animatesWhenAdded = true

                let accessButton = UIButton(frame: CGRect(x: 0, y: 0, width: 20, height: 20))
                accessButton.setImage(self.accessAnnotation, for: .normal) //UIImage(named: "accessAnnotation"), for: .normal)
                rightCalloutAccessoryView = accessButton
            }

            //collisionMode = .circle
        }

    }
}

}

向具有多个自定义注释视图的地图视图添加集群注释

Adding cluster annotations to a map view, which has several custom annotation views

mapkit

ios

mkmapviewdelegate

swift

swift4