'NSInvalidArgumentException' when using MapKit

Question

i'm creating a simple view controller with a map and 100-200 MKPointAnnotation using the iOS 11 MKMarkerAnnotationView

This is the viewDidLoad of the controller

 override func viewDidLoad() {
    super.viewDidLoad()
    self.mapView.register(StationAnnotationView.self, forAnnotationViewWithReuseIdentifier: MKMapViewDefaultAnnotationViewReuseIdentifier)
    self.mapView.register(StationClusterView.self, forAnnotationViewWithReuseIdentifier: MKMapViewDefaultClusterAnnotationViewReuseIdentifier)

    locationDelegate.delegate = self
    self.mapView.delegate = self
    self.mapView.showsUserLocation = true
    self.refreshData()
    self.establishUserPosition()
}

Then i download the stations from a JSON (network object) and i add all of them to the mapview

func reloadViews(){
    if let network = network{
        for station in network.stations{
            let annotation = StationAnnotation(station: station)
            annotations.append(annotation) // I add the annotations to an array to prevent them to be deallocated
            mapView.addAnnotation(annotation)
        }
    }
}

This is my personal annotation

class StationAnnotation : MKPointAnnotation{
var station : Station?
var tintColor : UIColor?{
    if self.station?.free_bikes ?? 0 > 0 {
        return .green
    }else{
        return .red
    }
}

var glyphImage : UIImage?{
    if self.station?.extra.status == "online"{
        return UIImage(named: "Bicycle")
    }else{
        return UIImage(named: "Ban")
    }
}

override init() {
    super.init()
}

convenience init(station : Station){
    self.init()
    self.title = station.name
    self.coordinate = CLLocationCoordinate2D(latitude: station.latitude, longitude: station.longitude)
    self.station = station
    if station.extra.status == "online"{
        self.subtitle =  "Bikes: \(station.free_bikes) - Slots: \(station.empty_slots)"
    }else{
        self.subtitle = station.extra.status
    }
}
}

And my customs Views

class StationAnnotationView : MKMarkerAnnotationView{

override var annotation: MKAnnotation? {
    willSet {
        if let annotation = newValue as? StationAnnotation{

            self.markerTintColor = annotation.tintColor
            self.clusteringIdentifier = "station"
            self.glyphImage = annotation.glyphImage
        }
    }
}
}


class StationClusterView: MKAnnotationView {

override init(annotation: MKAnnotation?, reuseIdentifier: String?) {
    super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
}

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 onlineCount = cluster.memberAnnotations.filter { member -> Bool in
                return (member as! StationAnnotation).station?.extra.status == "online"
                }.count
            image = renderer.image { _ in
                // Fill full circle with tricycle color
                UIColor(named: "Forbidden")?.setFill()
                UIBezierPath(ovalIn: CGRect(x: 0, y: 0, width: 40, height: 40)).fill()

                // Fill pie with unicycle color
                UIColor(named: "Available")?.setFill()
                let piePath = UIBezierPath()
                piePath.addArc(withCenter: CGPoint(x: 20, y: 20), radius: 20,
                               startAngle: 0, endAngle: (CGFloat.pi * 2.0 * CGFloat(onlineCount)) / 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: 20)]
                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)
            }
        }
    }
}

}

I don't know why the app while pinching , zooming, or panning, crash with SIGABRT signal and this exception

*** Terminating app due to uncaught exception 
'NSInvalidArgumentException', reason: '*** -[__NSDictionaryM setObject:forKey:]: key cannot be nil'

I've tried every kind of debug system and the use of exception breakpoint didn't helped... have you any suggestions?

Answer 1

Hllo everybody, i find solutions. At first - it s..t happens when we use

mapView.register(AnyClass?, forAnnotationViewWithReuseIdentifier: String) 

and

mapView.dequeueReusableAnnotationView(withIdentifier: String) 

returns nil.

So hot fix: Add:

ViewController: UIViewController, MKMapViewDelegate  

add

    override func viewDidLoad() {  
        super.viewDidLoad()  
        mapView.delegate = self  

        mapView.register(MarkerPointView.self, forAnnotationViewWithReuseIdentifier: "marker")  
        mapView.register(ClusterView.self, forAnnotationViewWithReuseIdentifier: "cluster")  
}  

and finaly:

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {  

        if let marker = annotation as? MarkerAnnotation{  
            var view = mapView.dequeueReusableAnnotationView(withIdentifier: "marker") as? MarkerPointView  
            if view == nil {  
//Very IMPORTANT  
                print("nil for Marker")  
                view = MarkerPointView(annotation: marker, reuseIdentifier: "marker")  
            }  
            return view  
        }else if let cluster = annotation as? MKClusterAnnotation{  
            var view = mapView.dequeueReusableAnnotationView(withIdentifier: "cluster") as? ClusterView  
            if view == nil{  
//Very IMPORTANT  
                print("nil for Cluster")  
                view = ClusterView(annotation: cluster, reuseIdentifier: "cluster")  
            }  
            return view  
        }  
        else{  
            return nil  
        }  
    }  

hope it's help for somebody, and on next revs apple fix it, because we can use it like they said on wwdc2017 on 36:50 - we CAN'T delete it!!!!!!!!

original post on forums.developer.apple.com