iphone - 在 Swift 中使用图像设置 map 注释

Question

我正在尝试将 map 注释更改为我在静态单元格中制作的自定义图像。 map 的注释有效，但是当我尝试将图像放入 map 中时， map 会缩放到该位置但不显示图像。

     import UIKit
            import MapKit
            import CoreLocation


        class ContactsTableViewController: UITableViewController, MKMapViewDelegate, CLLocationManagerDelegate {
    }

     override func viewDidLoad() {
            super.viewDidLoad()


        self.addressMap.delegate = self
    }

     override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

            let cell = tableView.dequeueReusableCell(withIdentifier: "ContactCell", for: indexPath) as! customCell

            if let _ = currentAnnotation {
                addressMap.removeAnnotation(currentAnnotation!)
            }


            let contact = contacts.contactWithIndex((indexPath as NSIndexPath).row)
            print(contact)
            cell.nameLabel.text = contact.name
            cell.addressLabel.text = contact.address

            let country = "USA"
            let city = "Cicero"
            let street = contact.address

            // Create Address String
            let address = "\(country), \(city), \(street)"

            // Geocode Address String
            geocoder.geocodeAddressString(address) { (placemarks, error) in
                // Process Response
                self.processResponse(withPlacemarks: placemarks, error: error)
                var location: CLLocation?

                if let placemarks = placemarks, placemarks.count > 0 {
                    location = placemarks.first?.location
                }

                if let location = location {
                    let coordinate = location.coordinate
                    print("Custom cell: \(coordinate.latitude), \(coordinate.longitude)")

                    //Drops pin to current MKPointAnnotationis logged in
                    self.currentAnnotation = MKPointAnnotation()
                    self.currentAnnotation?.coordinate = CLLocationCoordinate2D(latitude: coordinate.latitude, longitude: coordinate.longitude)

                    let image1 = CustomPointAnnotation()
                    image1.imageName = "mapPin.png"
                    self.addressMap.addAnnotation(image1)

                    //Pins the location on the mapview
                    //cell.addressMap.addAnnotation(self.currentAnnotation!)
                    cell.addressMap.addAnnotation(image1)
                    //Auto zoom into user location
                    let span = MKCoordinateSpanMake(0.02, 0.02)
                    let region = MKCoordinateRegion(center: (self.currentAnnotation?.coordinate)!, span: span)
                    cell.addressMap.setRegion(region, animated: true)

                } else {
                    print("No Matching Location Found")
                }
            }
    }


 func addressMap(_ addressMap: MKMapView, viewFor annotation: MKAnnotation!) -> MKAnnotationView? {
        if !(annotation is CustomPointAnnotation) {
           return nil
        }

        let reuseId = "test"
        var anView = addressMap.dequeueReusableAnnotationView(withIdentifier: reuseId)
        if anView == nil {
            anView = MKAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
            anView?.canShowCallout = true
        } else {
            anView?.annotation = annotation
        }

        //Set annotation-specific properties **AFTER**
        //the view is dequeued or created...

        let cpa = annotation as! CustomPointAnnotation
        anView?.image = UIImage(named:cpa.imageName)

        return anView
        }

这是注释的类

 import UIKit
import MapKit

class CustomPointAnnotation: MKPointAnnotation {
    var imageName: String!

}

如果有人能告诉我我做错了什么，导致我的图像无法显示为注释，那就太棒了。

Answer 1

几个问题:

1. 您似乎从未设置过 CustomPointAnnotation 的坐标。

2. mapView(_:viewFor:) 的签名是不正确的。如果您在方法中添加断点，您会看到它没有被调用。您的 map socket 可能名为 addressMap，但委托(delegate)方法名称为 mapView(_:viewFor:)，无论您的 MKMapView 的名称如何 socket 引用。