MK Directions Request - direction line is not shown - ios

Question

I have successfully implemented location of a point of interest and my location. Both is shown. Now, I would like to get calculated the route between two points and a blue line should be shown. Unfortunately, when I am clicking on the button, no line is being shown.
I really appreciate help/hints. Thanks so much.
import UIKit
import MapKit
class MapViewController: UIViewController, MKMapViewDelegate
{
//outlet variable is used for establishing a connection with the
// map view in the storyboard
#IBOutlet var mapView: MKMapView!
var spot = Spot()
let locationManager = CLLocationManager()
var currentPlacemark:CLPlacemark?// it is used to save the selected spot
override func viewDidLoad()
{
super.viewDidLoad()
//request for a user's authorization for lacation services
locationManager.requestWhenInUseAuthorization()
let status = CLLocationManager.authorizationStatus()
if status == CLAuthorizationStatus.authorizedWhenInUse
{
mapView.showsUserLocation = true
}
let geoCoder = CLGeocoder()
geoCoder.geocodeAddressString(spot.location,
completionHandler:
{ placemarks, error in
if let error = error {
print(error)
return
}
if let placemarks = placemarks{
//get the first placemark
let placemark = placemarks[0]
// value of current Placemark
self.currentPlacemark = placemark
// add annotation
let annotation = MKPointAnnotation()
annotation.title = self.spot.name
annotation.subtitle = self.spot.type
if let location = placemark.location{
annotation.coordinate = location.coordinate
//display the annotation
self.mapView.showAnnotations([annotation],animated:true)
self.mapView.selectAnnotation(annotation, animated: true)
}
}
})
mapView.showsCompass = true
mapView.showsTraffic = true
mapView.showsScale = true
// we want to show the users location
mapView.showsUserLocation = true
}
#IBAction func showDirection(sender:AnyObject)
{
// we make sure if current placemark contains a value using a guard statement. Otherwise just
// skip everything
guard let currentPlacemark = currentPlacemark else
{
return
}
// creating an instance of MKDirectionsRequest to request directions
let directionRequest = MKDirectionsRequest()
// set the source(where the user currently is) and destination of the route
directionRequest.source = MKMapItem.forCurrentLocation()// retrieving the current location
let destinationPlacemark = MKPlacemark(placemark:currentPlacemark)
directionRequest.destination = MKMapItem(placemark: destinationPlacemark)
directionRequest.transportType = MKDirectionsTransportType.automobile// later change for transit
// calculate the direction
let directions = MKDirections(request: directionRequest)
// this method initiates an asynchronous request for directions and calls
// your completion handler when the request is conpleted. The MKDirections object
//passes my request to the Apple servers ans asks for route-based directions data
directions.calculate { (routeRepsonse, routeError) -> Void in
guard let routeResponse = routeRepsonse else
{
if let routeError = routeError
{
print("Error:\(routeError)")
}
return
}
let route = routeRepsonse?.routes[0]// provides a container for saving the route information so that the routes are saved in the routes property
// The detailed route geometry is e.g. route.polyline is represented by an MKPolyline object
// the add level method is used to add an MKPolyline object to the existing map view
self.mapView.add((route?.polyline)!,level: MKOverlayLevel.aboveRoads)
}
}
// implementing a mapView method which draws the route
func mapView(_mapView:MKMapView,rendererFor overlay: MKOverlay) -> MKOverlayRenderer
{
let renderer = MKPolylineRenderer(overlay: overlay)
renderer.strokeColor = UIColor.blue
renderer.lineWidth = 3.0
return renderer
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources hat can be recreated.
}
}

Answer 1

Maybe delegate method name is wrong. Rename
func mapView(_mapView:MKMapView,rendererFor overlay: MKOverlay) -> MKOverlayRenderer
with
func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer