Using delegate with a static function in Swift - swift

Question

This is a function that I use it in my app, it works perfectly.
class ResenhaEquideosMenuController: UIViewController, CLLocationManagerDelegate {
static let locationManager = CLLocationManager()
func getLocation() {
let status = CLLocationManager.authorizationStatus()
switch status {
case .notDetermined:
locationManager.requestWhenInUseAuthorization()
return
case .denied, .restricted:
let alert = UIAlertController(title: "Serviços de localização desativados", message: "Por favor, ative os Serviços de Localização nas Configurações do seu dispositivo", preferredStyle: .alert)
let okAction = UIAlertAction(title: "OK", style: .default, handler: nil)
alert.addAction(okAction)
present(alert, animated: true, completion: nil)
return
case .authorizedAlways, .authorizedWhenInUse:
break
}
locationManager.delegate = self
locationManager.startUpdatingLocation() // função didUpdateLocations controla quando GPS capta atualização do Sensor
}
}
But I wanna change this function to a static function just like
static func getLocation() { // some code }
But I got en error on this part of the code
locationManager.delegate = self
Cannot assign value of type 'ResenhaEquideosMenuController.Type' to type 'CLLocationManagerDelegate?'
How can I fix that?

Answer 1

Static functions don't depend on any particular instance of the type that they belong to, so referencing self from inside one as you're doing:
locationManager.delegate = self
doesn't make any sense. self represents a particular object that provides context for the function call, and that's not available to a static function.
How can I fix that?
You're going to have to reconsider your reason for wanting to make getLocation static, and find a different approach.

Answer 2

I didn't find a way to use the delegate with a static function to fix my problem with the CCLocationManager class.
So, based in #DuncanC comment, I create a new class that extends a UIViewController called LocationViewController.
import Foundation
import CoreLocation
class LocationViewController: UIViewController, CLLocationManagerDelegate {
let locationManager = CLLocationManager()
override func viewDidLoad() {
super.viewDidLoad()
print("___ LocationViewController viewDidLoad")
getLocation()
}
func getLocation() {
let status = CLLocationManager.authorizationStatus()
switch status {
case .notDetermined:
locationManager.requestWhenInUseAuthorization()
return
case .denied, .restricted:
let alert = UIAlertController(title: "Serviçoõs de localização desativados", message: "Por favor, ative os Serviços de Localização nas Configurações do seu dispositivo", preferredStyle: .alert)
let okAction = UIAlertAction(title: "OK", style: .default, handler: nil)
alert.addAction(okAction)
present(alert, animated: true, completion: nil)
return
case .authorizedAlways, .authorizedWhenInUse:
break
#unknown default:
print("erro desconhecido")
}
locationManager.delegate = self
locationManager.startUpdatingLocation() // função didUpdateLocations controla quando GPS capta atualização do Sensor
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
if let currentLocation = locations.last {
manager.distanceFilter = 50 // distance changes you want to be informed about (in meters)
manager.desiredAccuracy = 10 // biggest approximation you tolerate (in meters)
//manager.activityType = .automotiveNavigation // .automotiveNavigation will stop the updates when the device is not moving
saveLocationPosition(currentLocation)
}
}
fileprivate func saveLocationPosition(_ currentLocation: CLLocation) {
UserDefaults.standard.set(currentLocation.coordinate.latitude, forKey: RESconstantes.LATITUDE_USER)
UserDefaults.standard.set(currentLocation.coordinate.longitude, forKey: RESconstantes.LONGITUDE_USER)
}
func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
print("locationManager error")
print(error)
}
}
When I want to capture the location of the GPS sensor, I just extend a UIViewController using the LocateViewController.
Just like that example below:
class ResenhaEquideosMenuController: LocationViewController { ...code }
It works for me.