Xcode Warning When Using Mapkit and Corelocation

Xcode warning when using MapKit and CoreLocation

You are calling requestWhenInUseAuthorization, that is true. But are you waiting until you get authorization? No, you are not. You (as the user) are tapping Allow, but that's happening too late: your code has already continued, going straight on to tell the map view to start tracking the user's location.

Just look at the docs on requestWhenInUseAuthorization:

When the current authorization status is kCLAuthorizationStatusNotDetermined, this method runs asynchronously

Get that? Runs asynchronously. That means that asking for permission happens in the background on another thread.

And the docs go on to say:

After the status is determined, the location manager delivers the results to the delegate’s locationManager:didChangeAuthorizationStatus: method

So, implement that method. If you have just obtained permission, that is the signal that you can start using the location manager.

Also, you are missing an important step: you are not checking what the status actually is. You should only be asking for authorization if the status is undetermined. If the status is restricted or denied, you must not use the location manager at all; and if the status is granted, there is no point asking for authorization again.

So, just to sum up, your logical flowchart should be:

• Check status.

• Is the status Restricted or Denied? Stop. You cannot use get location updates or do location on a map.

• Is the status Granted? Proceed to get location updates or do location on a map.

• Is the status Undetermined? Request authorization and stop. Treat locationManager:didChangeAuthorizationStatus: as the completion handler for your authorization request. At that point, go back to start of the flowchart!

CoreLocation Swift

First,make sure you have this key in plist

Second,request location service in viewDidLoad,I test with these code

import UIKit
import CoreLocation

class ViewController: UIViewController,CLLocationManagerDelegate {
var manager:CLLocationManager!
override func viewDidLoad() {
    super.viewDidLoad()
    manager = CLLocationManager()
    manager.delegate = self
    if(NSString(string:UIDevice.currentDevice().systemVersion).doubleValue >= 8.0){
        manager.requestWhenInUseAuthorization()
    }
    // Do any additional setup after loading the view, typically from a nib.
}
func locationManager(manager: CLLocationManager!,
    didChangeAuthorizationStatus status: CLAuthorizationStatus){
        
        print("The authorization status of location " +
            "services is changed to: ")
        
        switch CLLocationManager.authorizationStatus(){
        case .Denied:
            println("Denied")
        case .NotDetermined:
            println("Not determined")
        case .Restricted:
            println("Restricted")
        default:
            println("Authorized")
        }
        
}

And get output

You have to run this on device and if you can not get alert,try uninstall the app,then run again

Problems drawing poly Line in Map Kit

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()
}

}

User location in mapView doesn't show on several simulator devices (MapKit)

I ended up solving my own question.

I just added this line of code in viewDidLoad:

 [self.locationManager requestWhenInUseAuthorization];

This was very helpful: http://nevan.net/2014/09/core-location-manager-changes-in-ios-8/

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