Open SwiftUI view only if location permission granted - ios

Question

I have a view (say V) in which a user answers a few questions and their location is recorded. However, the answers only make sense with the user's location.
So what I want is that when the user clicks on a button on the parent view, it takes them to V and immediately asks them for the location permission. If they accept, they can continue on to answer the questions, but if they deny, they navigate back to the parent screen.
I know I can navigate back to the parent screen with self.presentation.wrappedValue.dismiss().
But how do I know when the user has accepted or denied the permission since requestWhenInUseAuthorization() is an asynchronous function?
I'm following this tutorial on getting a user's location on iOS with Swift.
Code for my LocationService:
import CoreLocation
protocol LocationServiceDelegate {
func didFetchCurrentLocation(_ location: GeoLocation)
func fetchCurrentLocationFailed(error: Error)
}
class LocationService: NSObject, CLLocationManagerDelegate {
let locationManager = CLLocationManager()
var delegate: LocationServiceDelegate
init(delegate: LocationServiceDelegate) {
self.delegate = delegate
super.init()
self.setupLocationManager()
}
private func setupLocationManager() {
if canUseLocationManager() {
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
}
}
func requestLocation() {
if canUseLocationManager() {
print(CLAuthorizationStatus.self)
locationManager.requestWhenInUseAuthorization()
locationManager.requestLocation()
}
}
func requestPermission() {
locationManager.requestWhenInUseAuthorization()
}
private func canUseLocationManager() -> Bool {
return CLLocationManager.locationServicesEnabled()
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
print(locations)
if let location = locations.last {
let geoLocation = GeoLocation(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
delegate.didFetchCurrentLocation(geoLocation)
}
}
func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
print(error)
delegate.fetchCurrentLocationFailed(error: error)
}
deinit {
locationManager.stopUpdatingLocation()
}
}
struct GeoLocation {
var latitude: Double
var longitude: Double
}

Answer 1

CLLocationManagerDelegate has also the following method:
func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
}
This method is called every time the authorization status changed. I would also like to recommend you implementing your LocationService as an ObservableObject instead of using delegate approach.