Swift requestWhenInUseAuthorization not working

Question

I'm writing an app for iOS 9.3 using swift and need a map to show user location. I initialize CLLocationManager and its delegate, I configure info.plist Privacy - Location Usage Description string and invoke requestWhenInUseAuthorization but it does not show any authorization request.

Here is my code:

import UIKit
import MapKit

class DetailController: UIViewController, CLLocationManagerDelegate {

    var locManager: CLLocationManager!

    @IBOutlet var myMap: MKMapView!

    override func viewDidLoad() {
        super.viewDidLoad()

        mostraPosizione()
    }

    func mostraPosizione(){
        locManager = CLLocationManager()
        locManager.delegate = self
        locManager.desiredAccuracy = kCLLocationAccuracyBest

        let authorizationStatus = CLLocationManager.authorizationStatus()

        if (authorizationStatus == CLAuthorizationStatus.NotDetermined) {
            locManager.requestWhenInUseAuthorization()
        } else {
            locManager.startUpdatingLocation()
        }


        myMap.showsUserLocation = true
    }

    func locManager(manager: CLLocationManager, 
    didChangeAuthorizationStatus status: CLAuthorizationStatus) {

        if (status == CLAuthorizationStatus.NotDetermined) {
            locManager.requestWhenInUseAuthorization()

        } else {
            locManager.startUpdatingLocation()
        }
    }
}

and a screenshot from my info.plist

Xcode output:

Trying to start MapKit location updates without prompting for location authorization. Must call -[CLLocationManager requestWhenInUseAuthorization] or -[CLLocationManager requestAlwaysAuthorization] first.

I'm testing it on iPhone 5 s (iOS 9.3) simulator.

What's the problem with this stuff? Does anyone have any advice?

Answer 1

Try this on for size:

override func viewDidLoad() {
    super.viewDidLoad()

    //put code here
    locManager = CLLocationManager()
    locManager.delegate = self
    locManager.desiredAccuracy = kCLLocationAccuracyBest
}

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)

    //make sure the view is loaded first before adding subviews
    mostraPosizione()
}

func mostraPosizione(){
    let authorizationStatus = CLLocationManager.authorizationStatus()

    if (authorizationStatus == .authorizedWhenInUse) {
        locManager.startUpdatingLocation()
        myMap.showsUserLocation = true
    } else {
        locManager.requestWhenInUseAuthorization()
        mostraPosizione()
    }
}

The reason the request was not showing up was because the view was not completed loaded when the request was called. Using viewDidAppear() fixes that issue.

I made some changes to the code as well, which seems to work great. I only made changes to the code below, other functions remained the same.

I'm writing this code in Swift 3, but the principals are the same.