Problems drawing poly Line in Map Kit

Question

Good afternoon Community,

I am having trouble plotting the Poly Line within my application, I already tried calling it in the func method locationManager (_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {}

but nothing is generated, just as I would like each step that I take the polyline to be marked and not at the end of my journey. I leave my code below:

 import UIKit
import MapKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate,MKMapViewDelegate {


@IBOutlet var Maps: MKMapView!
var locationManager = CLLocationManager()
var coordenadas = CLLocationCoordinate2D()
var startPoint = MKDirections.Request()
var ArrayDeCoordenadas: [CLLocationCoordinate2D] = []
var tap: Int = 0

func getDirections(){

    let request = MKDirections.Request()
    request.source = MKMapItem.forCurrentLocation()

       request.requestsAlternateRoutes = true

       let directions = MKDirections(request: request)
    directions.calculate { (response, error) in

           if error != nil {

               print("Error \(error)")


           } else {


               //self.dispLayRout(response)
            var overlays = self.Maps.overlays
               self.Maps.removeOverlays(overlays)

               for route in response!.routes as! [MKRoute] {

                   self.Maps.addOverlay(route.polyline,
                                        level: MKOverlayLevel.aboveRoads)

                   var instructionNumber = 0
                   for next  in route.steps {
                       instructionNumber += 1
                       print(next.instructions)
                   }

               }
           }

    }
}

   func alertLocation(title: String, Message:String){

       let alert = UIAlertController(title: title, message: Message, preferredStyle: .alert)
       let actionAlert = UIAlertAction(title: "Acept", style: .default, handler: nil)
       alert.addAction(actionAlert)
       self.present(alert, animated: true,completion: nil)

   }

   func LocalizationInit(){
       let autorization = CLLocationManager.authorizationStatus()
       switch autorization{
       case .notDetermined, .restricted:
           locationManager.requestLocation()
           break;
       case .restricted, .denied:
           alertLocation(title: "We have a Error", Message: "You have your localization restricted.")
       case .authorizedAlways,.authorizedWhenInUse:

           break;
       default:
           break;
       }
   }


@IBAction func Share(_ sender: UIButton) {
    let compartir = UIActivityViewController(activityItems: ["Share baby" as Any], 
      applicationActivities: nil)
    compartir.popoverPresentationController?.sourceView = self.view
    present(compartir,animated: true,completion: nil)
}

@IBAction func recordButton(_ sender: UIButton) {

    if sender.isSelected != true {
        tap += 1
        print("tap -> :\(tap)")
        if tap == 1{
            let annotation = MKPointAnnotation()
            annotation.title = "My route"
            annotation.subtitle = "I Hoppe"
            annotation.coordinate = coordenadas
            let annotation2 = MKPointAnnotation()
            annotation2.title = "My ride"
            annotation2.subtitle = "I Hoppe"
            annotation.coordinate = locationManager.location?.coordinate as! CLLocationCoordinate2D
            self.Maps.addAnnotation(annotation)


        }else if tap == 2 {
            tap = 0
            locationManager.stopMonitoringSignificantLocationChanges()


        }
    }

}
@IBAction func mapOptions(_ sender: UISegmentedControl) {
    switch sender.selectedSegmentIndex{
    case 0:
        Maps.mapType = MKMapType.standard
        break;
    case 1:
        Maps.mapType = MKMapType.satellite
        break;
    case 2:
        Maps.mapType = MKMapType.hybrid
        break;
    default:
        break;
    }
}



override func viewDidLoad() {
    super.viewDidLoad()


    LocalizationInit()
    let polyLineMake = MKPolyline(coordinates: ArrayDeCoordenadas, count: ArrayDeCoordenadas.count)
    self.Maps.addOverlay(polyLineMake, level: .aboveRoads)
    Maps.showsUserLocation = true
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation
     DispatchQueue.main.async {
           self.locationManager.startUpdatingLocation()
       }
}

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {


    coordenadas = manager.location?.coordinate as! CLLocationCoordinate2D
    ArrayDeCoordenadas.append(locations.last!.coordinate)
    print("Array de coordenadas : ->  \(ArrayDeCoordenadas)")
    let region  = MKCoordinateRegion(center: locations.last!.coordinate, latitudinalMeters: 200, 
 longitudinalMeters: 200)
    self.Maps.setRegion(region, animated: false)
    let distancia = locations.distance(from: Int(manager.location!.coordinate.latitude), to: 
    Int((locations.last?.coordinate.latitude)!))
    print("distancia \(distancia)")

}


func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation{
        return nil
    }
    let pin = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "My personal pin")
    pin.pinTintColor = UIColor.green
    return pin
}

func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
    if overlay is MKPolyline{
        let polyline = overlay
        let polyLineRender = MKPolylineRenderer(overlay: polyline)
        print(" se esta generando \(polyline)")
        polyLineRender.strokeColor = UIColor.red
        polyLineRender.lineWidth = 6.0
        return polyLineRender
    }
    print(" no se esta generando")
    return MKPolylineRenderer()
} }

I have read the documentation a bit and apparently my code is fine, if someone could help me, it would be of great help. Like someone if you have any method that can help me to know when I did and how many steps I walked since I did not see that CLLocation had an option for that type of information.

Answer 1

the problem is not set Map delegate object, also I made some changes to add polyline overlay. Simple but it is working. Good luck.

Maps.delegate = self

Code file:

import UIKit
import MapKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate,MKMapViewDelegate {


@IBOutlet var Maps: MKMapView!
var locationManager = CLLocationManager()
var coordenadas = CLLocationCoordinate2D()
var startPoint = MKDirections.Request()
var ArrayDeCoordenadas: [CLLocationCoordinate2D] = []
var tap: Int = 0
var journeyPolyline: MKPolyline?

func getDirections(){

    let request = MKDirections.Request()
    request.source = MKMapItem.forCurrentLocation()

    request.requestsAlternateRoutes = true

    let directions = MKDirections(request: request)
    directions.calculate { (response, error) in

        if error != nil {

            print("Error \(error)")


        } else {


            //self.dispLayRout(response)
            var overlays = self.Maps.overlays
            self.Maps.removeOverlays(overlays)

            for route in response!.routes as! [MKRoute] {

                self.Maps.addOverlay(route.polyline,
                                     level: MKOverlayLevel.aboveRoads)

                var instructionNumber = 0
                for next  in route.steps {
                    instructionNumber += 1
                    print(next.instructions)
                }

            }
        }

    }
}

func alertLocation(title: String, Message:String){

    let alert = UIAlertController(title: title, message: Message, preferredStyle: .alert)
    let actionAlert = UIAlertAction(title: "Acept", style: .default, handler: nil)
    alert.addAction(actionAlert)
    self.present(alert, animated: true,completion: nil)

}

func LocalizationInit(){
    let autorization = CLLocationManager.authorizationStatus()
    switch autorization{
    case .notDetermined, .restricted:
        locationManager.requestWhenInUseAuthorization()
        locationManager.startUpdatingLocation()
        break;
    case .restricted, .denied:
        alertLocation(title: "We have a Error", Message: "You have your localization restricted.")
    case .authorizedAlways,.authorizedWhenInUse:
        locationManager.startUpdatingLocation()
        break;
    default:
        break;
    }
}


@IBAction func Share(_ sender: UIButton) {
    let compartir = UIActivityViewController(activityItems: ["Share baby" as Any],
                                             applicationActivities: nil)
    compartir.popoverPresentationController?.sourceView = self.view
    present(compartir,animated: true,completion: nil)
}

@IBAction func recordButton(_ sender: UIButton) {

    if sender.isSelected != true {
        tap += 1
        print("tap -> :\(tap)")
        if tap == 1{
            let annotation = MKPointAnnotation()
            annotation.title = "My route"
            annotation.subtitle = "I Hoppe"
            annotation.coordinate = coordenadas
            let annotation2 = MKPointAnnotation()
            annotation2.title = "My ride"
            annotation2.subtitle = "I Hoppe"
            annotation.coordinate = locationManager.location?.coordinate as! CLLocationCoordinate2D
            self.Maps.addAnnotation(annotation)


        }else if tap == 2 {
            tap = 0
            locationManager.stopMonitoringSignificantLocationChanges()


        }
    }

}
@IBAction func mapOptions(_ sender: UISegmentedControl) {
    switch sender.selectedSegmentIndex{
    case 0:
        Maps.mapType = MKMapType.standard
        break;
    case 1:
        Maps.mapType = MKMapType.satellite
        break;
    case 2:
        Maps.mapType = MKMapType.hybrid
        break;
    default:
        break;
    }
}



override func viewDidLoad() {
    super.viewDidLoad()


    LocalizationInit()
    //    let polyLineMake = MKPolyline(coordinates: ArrayDeCoordenadas, count: ArrayDeCoordenadas.count)
    //    self.Maps.addOverlay(polyLineMake, level: .aboveRoads)
    Maps.showsUserLocation = true
    Maps.delegate = self
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation
}

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    coordenadas = locations.first!.coordinate as! CLLocationCoordinate2D
    ArrayDeCoordenadas.append(locations.last!.coordinate)
    print("Array de coordenadas : ->  \(ArrayDeCoordenadas)")
    let region  = MKCoordinateRegion(center: locations.last!.coordinate, latitudinalMeters: 200,
                                     longitudinalMeters: 200)
    self.Maps.setRegion(region, animated: false)
    let distancia = locations.distance(from: Int(manager.location!.coordinate.latitude), to:
        Int((locations.last?.coordinate.latitude)!))
    print("distancia \(distancia)")

    let polyline = MKPolyline(coordinates: ArrayDeCoordenadas, count: ArrayDeCoordenadas.count)
    Maps.addOverlay(polyline)

    //remove old polyline
    if let oldPolyline = journeyPolyline {
        Maps.removeOverlay(oldPolyline)
    }

    journeyPolyline = polyline
}


func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation{
        return nil
    }
    let pin = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "My personal pin")
    pin.pinTintColor = UIColor.green
    return pin
}


func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
    if overlay is MKPolyline{
        let polyline = overlay
        let polyLineRender = MKPolylineRenderer(overlay: polyline)
        print(" se esta generando \(polyline)")
        polyLineRender.strokeColor = UIColor.red
        polyLineRender.lineWidth = 6.0
        return polyLineRender
    }
    print(" no se esta generando")
    return MKPolylineRenderer()
}

}