ios - 如何使用 swift 2 和 xcode 7 在 MapKit 中使注释点可拖动？

Question

找到这个问题的解决方案非常令人沮丧。我发布了整个代码以了解问题。请帮忙

import UIKit
import MapKit
import CoreLocation
class LocationViewController: UIViewController,MKMapViewDelegate, CLLocationManagerDelegate {


    @IBOutlet weak var mapView: MKMapView!

    let locationManager = CLLocationManager()
    var annotationPoint: MKPointAnnotation!
    var getMovedMapCenter: CLLocation!
    var myPinView:MKPinAnnotationView!
    override func viewDidLoad() {
        super.viewDidLoad()

        self.locationManager.delegate = self
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
        if #available(iOS 8.0, *) {
            self.locationManager.requestWhenInUseAuthorization()
        } else {
            // Fallback on earlier versions
        }
        self.locationManager.startUpdatingLocation()
        self.mapView.showsUserLocation = true

        // Do any additional setup after loading the view.
    }

    // MARK: - Location Delegate Methods

    func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation])
    {
        let location = locations.last

        let center = CLLocationCoordinate2D(latitude: location!.coordinate.latitude, longitude: location!.coordinate.longitude)

        let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 1, longitudeDelta: 1))

        self.mapView.setRegion(region, animated: true)

        if(self.annotationPoint == nil)
        {
            self.annotationPoint = MKPointAnnotation()
            getMovedMapCenter =  CLLocation(latitude: location!.coordinate.latitude, longitude: location!.coordinate.longitude)

             self.annotationPoint.coordinate = getMovedMapCenter.coordinate

            // self.annotationPoint.title = location_value
            //self.annotationPoint.subtitle = ""

            // println_debug(self.annotationPoint)

            self.mapView.addAnnotation(self.annotationPoint)

        }

        self.locationManager.stopUpdatingLocation()
    }

    func locationManager(manager: CLLocationManager, didFailWithError error: NSError)
    {
        print("Errors: " + error.localizedDescription)
    }

    //MARK:- View for Annotation
    func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView?
    {
        if annotation is MKPointAnnotation {
            let pinAnnotationView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "myPin")

            pinAnnotationView.pinColor = .Purple
            pinAnnotationView.draggable = true
            pinAnnotationView.canShowCallout = true
            pinAnnotationView.animatesDrop = true

            return pinAnnotationView
        }

        return nil
    }

    //MARK:- Annotation Changed State

    func mapView(mapView: MKMapView, annotationView view: MKAnnotationView, didChangeDragState newState: MKAnnotationViewDragState, fromOldState oldState: MKAnnotationViewDragState) {

        print("hiii")


        //        println_debug("End State coordinates: \(self.annotationPoint.coordinate.latitude),\(self.annotationPoint.coordinate.longitude)")


        if(newState == .Ending)
        {


            let center = CLLocationCoordinate2D(latitude: self.annotationPoint.coordinate.latitude, longitude: self.annotationPoint.coordinate.longitude)
            //    self.currentLocationNameA(center)

            //            dispatch_async(GlobalBackgroundQueue)
            //                {
            //
            //
            //            }
        }

    }

    //MARK:- update Not Get

    func mapView(mapView: MKMapView,
        didFailToLocateUserWithError error: NSError)
    {
        // AppHelper.showALertWithTag(121, title: APP_NAME, message: "Failed to get location. Please check Location setting", delegate: nil, cancelButtonTitle: "Ok", otherButtonTitle: nil)

    }




}

我被这段代码卡住了。因为 didChangeDragState Delegate 从未调用过。请帮助我为此找到更好的解决方案。我是 swift 的新手；所以很难在swift中转换objective c代码

Answer 1

The drag state typically changes in response to user interactions with the annotation view. However, the annotation view itself is responsible for changing that state as well.

替换此方法并尝试一次。可能工作正常

func mapView(mapView: MKMapView!, annotationView view: MKAnnotationView!, didChangeDragState newState: MKAnnotationViewDragState, fromOldState oldState: MKAnnotationViewDragState) {
    switch (newState) {
    case .Starting:
        view.dragState = .Dragging
    case .Ending, .Canceling:
        view.dragState = .None
    default: break
    }
}

用这个替换你的点注释方法。

let pa = MKPointAnnotation()
pa.coordinate = placemark.location.coordinate
pa.title = placemark.name //or whatever title you like
self.mapView.addAnnotation(pa)

更多可以看Code和 Another Sample Code