MKPointAnnotation到MKMapItem

Question

当我试图打开苹果地图获取方向时，我收到了一个错误“无法将'NSKVONotifying_MKPointAnnotation‘类型的值转换为'MKMapItem'”。我在这方面是新手，我一直在拼凑代码，试图让它工作。

struct Location {
    let agencyId: String
    let agencyEventId: String
    let agencyEventSubTypeCode: String
    let latitude: Double
    let longitude: Double
    let agencyEventTypeCode: String
}

func multiPoint() {

    for receivedEvent in receivedEventsList {
        mapEventLatitude = receivedEvent.latitude!
        mapEventLongitude = receivedEvent.longitude!
        latDouble = ("\(mapEventLatitude))" as NSString).doubleValue
        longDouble = ("\(mapEventLongitude))" as NSString).doubleValue
        multiMapAgencyEventSubTypeCode = receivedEvent.agencyEventSubtypeCode!
        multiMapAgencyId = receivedEvent.agencyId!
        multiMapAgencyEventId = receivedEvent.agencyEventId!
        multiMapAgencyEventTypeCode = receivedEvent.agencyEventTypeCode!

        let locations = [
            Location(agencyId: multiMapAgencyId, agencyEventId: multiMapAgencyEventId, agencyEventSubTypeCode: multiMapAgencyEventSubTypeCode, latitude: latDouble, longitude: longDouble, agencyEventTypeCode: multiMapAgencyEventTypeCode)
            ]


        for location in locations {
            let annotation = MKPointAnnotation()
            annotation.coordinate = CLLocationCoordinate2D(latitude: location.latitude, longitude: location.longitude)
            annotation.title = location.agencyId
            annotation.subtitle = multiMapAgencyEventSubTypeCode
            multiEventMap?.addAnnotation(annotation)
            eventTypeNumber = ("\(multiMapAgencyEventTypeCode))" as NSString).intValue
        }
    }
}

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    let reuseIdentifier = "annotationView"
    let view = MKMarkerAnnotationView(annotation: annotation, reuseIdentifier: reuseIdentifier)
        view.markerTintColor = UIColor.blue
        view.glyphText = "x"
        view.displayPriority = .required
        view.clusteringIdentifier = nil
        view.canShowCallout = true
        view.rightCalloutAccessoryView = UIButton(type: .detailDisclosure)
    return view
}

func mapView(_ mapView: MKMapView, annotationView view: MKAnnotationView, calloutAccessoryControlTapped control: UIControl) {
    let location =  view.annotation as! MKMapItem
    let launchOptions = [MKLaunchOptionsDirectionsModeKey: MKLaunchOptionsDirectionsModeDriving]
    location.openInMaps(launchOptions: launchOptions)
}

Answer 1

当您将注释添加到地图中时，您将它们添加为MKPointAnnotation，因此到MKMapItem的强制转换显然会失败。

我建议您不要创建MKPointAnnotation，而是创建一个MKPlacemark，或者创建您自己的MKPlacemark子类，其中包含您感兴趣的其他属性。然后你的calloutAccessoryControlTapped就可以

• 将view.annotation转换为您的地标类型；
• 使用该地标创建MKMapItem；以及