ios, displaying an alert before everything else, to inform user we'll need "some" permissions

Question

i'm developing an app. One of the firs thing i do (in AppDelegate) is to invoke OneSignal's initwithlaunchingoptions(...) This automatically makes my app displays "App wants to send notifications", asking for permissions. During my app lifecycle, i'll need other permissions from user (like calendar). I'd like to display (BEFORE all the permissions) a brief AlertView explaining what i'll ask and why. But how can i accomplish this if i can't move the OneSignal init from AppDelegate while my "explaining alert" happens only in viewDidLoad of the Main ViewController ?

Thanks.

Victor

Answer 1

here is an example of UIViewController that has information about applications needs location data, when user presses UIButton, it asks for permission. you can do alike for all permissions.

class LocationRequestViewController: UIViewController, CLLocationManagerDelegate {

    var locationManager = CLLocationManager()

    override func viewDidLoad() {
        super.viewDidLoad()
        self.locationManager.delegate = self
    }

    //when user authorised or denied ->push next `UIViewController`
    func locationManager(_: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
        if status == .authorizedWhenInUse || status == .denied {
            let destinationVC = self.storyboard!.instantiateViewController(withIdentifier: "Notifications Request")
            self.navigationController?.pushViewController(destinationVC, animated: true)
        }
    }

    @IBAction func requestLocation(_: UIButton) {
        self.locationManager.requestWhenInUseAuthorization()
    }
}