ios - MapKit Direction to Selected 注释

Question

试图从用户的当前位置获取到 map 上所选注释的方向，但不确定如何捕获所选注释(当用户选择其中一个时)并显示方向。检查了 Stack 上的不同主题，但没有很多关于如何捕捉选择的注释并显示用户位置方向的新鲜信息。请指教。

import UIKit
import MapKit
import CoreLocation

class NavigationVC: UIViewController {

@IBOutlet weak var mapView: MKMapView!
let manager = CLLocationManager()
let request = MKLocalSearchRequest()

override func viewDidLoad() {
    super.viewDidLoad()

    manager.delegate = self
    manager.desiredAccuracy =   kCLLocationAccuracyBest
    manager.requestWhenInUseAuthorization()
    manager.startUpdatingLocation()


  }


 }
 //MARK: CONFIGURATION OF MAPVIEW

 extension NavigationVC: CLLocationManagerDelegate {

  func locationManager(_ manager: CLLocationManager, didUpdateLocations 
    locations: [CLLocation]) {
    let location = locations[0]
    let span: MKCoordinateSpan = MKCoordinateSpanMake(0.1, 0.1 )
    let userLocation:CLLocationCoordinate2D = 
    CLLocationCoordinate2DMake(location.coordinate.latitude, 
    location.coordinate.longitude)
    let region: MKCoordinateRegion = 
    MKCoordinateRegionMake(userLocation, span)
    mapView.setRegion(region, animated: true)
    self.mapView.showsUserLocation = true

    request.naturalLanguageQuery = "Currency exchange"
    request.region = mapView.region
    let activeSearch = MKLocalSearch(request: request)
    activeSearch.start { (response, error) in

        guard let response = response else {
            return
        }

        for item in response.mapItems {
            let annotation = MKPointAnnotation()
            annotation.coordinate = item.placemark.coordinate
            annotation.title = item.name

            DispatchQueue.main.async {
                self.mapView.addAnnotation(annotation)
            }
        }
    }


  }

  func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> 
 MKOverlayRenderer {
    let polylineRenderer = MKPolylineRenderer(overlay: overlay)
    polylineRenderer.strokeColor = UIColor.blue
    polylineRenderer.fillColor = UIColor.red
    polylineRenderer.lineWidth = 2
    return polylineRenderer


  }

}

Answer 1

要获取 map 上从您的位置到注释的路径，请遵循以下代码:

    annotation = MKPointAnnotation()
    annotation.coordinate = CLLocationCoordinate2D(latitude: CLLocationDegrees(lat),longitude: CLLocationDegrees(lon))
    self.map?.addAnnotation(annotation)


    var route : MKRoute? = nil

    DispatchQueue.global(qos: .userInitiated).async { [weak self] in
        let directionRequest = MKDirectionsRequest()
        directionRequest.source = MKMapItem.forCurrentLocation();
        directionRequest.destination = MKMapItem(placemark: MKPlacemark(coordinate:(self?.annotation.coordinate)!))
        directionRequest.transportType = .automobile
        let directions = MKDirections(request: directionRequest)

        directions.calculate {
            (response, error) -> Void in
            guard let response = response else {
                if let error = error {
                    print("Error: \(error)")
                }
                return
            }

            route = response.routes[0]
            if let percorso = route{
                DispatchQueue.main.async { [weak self] in
                    self?.map?.add((percorso.polyline), level: MKOverlayLevel.aboveRoads)
                }
            }
        }
    }

你只需要选择正确的注释，也许可以尝试在注释上注册一个触摸监听器。