CoreLocation Delegate functions do not run until view controller viewDidLoad function is finished - ios

Question

This is more than likely something very easy to solve but I've been at it for some time and can't seem to get at an answer.
I would like to know why a Delegate method for CLLocationManager does not trigger until after the ViewDidLoad function when the CLLocationManager is loaded within the ViewDidLoad function.
I have set my default region to Sydney Australia within my App Scheme and I have encapsulated my locationManager within its own class as follows:
import UIKit
import CoreLocation
/* Class location is a class to track user location and return a location object. */
class usrLocation: NSObject, CLLocationManagerDelegate
{
//MARK: Properties
var locationMgr: CLLocationManager!
var location: CLLocation!
var seenError: Bool = false
//MARK: Public Methods
func startTracking() {
locationMgr = CLLocationManager()
locationMgr.delegate = self
locationMgr.desiredAccuracy = kCLLocationAccuracyBest
locationMgr.requestWhenInUseAuthorization()
locationMgr.startUpdatingLocation()
}
//Return a location object
func getLocation() -> CLLocation {
locationMgr.startUpdatingLocation()
return location!
}
//MARK: CLLocationManagerDelegate
func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
locationMgr.stopUpdatingLocation()
if (seenError == false) {
seenError = true
print(error)
}
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
location = (locations ).last
locationMgr.stopUpdatingLocation()
}
}
I have initialised the class in my ViewController and try to begin tracking my current location in viewDidLoad.
The code looks like this.
override func viewDidLoad() {
var location = usrLocation()
override func viewDidLoad() {
super.viewDidLoad()
// Track location
location.startTracking()
location.getLocation()
//update Label text
sLongitude.text = "\(location.getLocation().coordinate.longitude)"
sLatitude.text = "\(location.getLocation().coordinate.latitude)"
}
getLocation() never returns location as it is always nil as the delegate didUpdateLocations function does not run. Why is this?

Answer 1

I tried to get this working using a completion handler but couldn't so my solution has been to ignore setting the label text via viewDidLoad and to instead update the labels once the location variable has been set. That way viewDidLoad completes, the delegate gets called and the labels get updated.
var location: CLLocation! {
didSet {
//update Label text
sLongitude.text = "\(location.getLocation().coordinate.longitude)"
sLatitude.text = "\(location.getLocation().coordinate.latitude)"
}
}