requestWhenInUseAuthorization() not Work in iOS 8 With NSLocationWhenInUseUsageDescription Key in Info.plist

问题

I am using iOS SDK 8.1 trying to call requestWhenInUseAuthorization() method to prompt user to grant access to my app. I imported CoreLocation.framework, and added NSLocationWhenInUseUsageDescription and NSLocationAlwaysUsageDescription keys into info.plist. When I ran the app, it never prompted me for location access. Below is my code, what have I missed?

import UIKit
import CoreLocation
import MapKit

class ViewController: UIViewController, CLLocationManagerDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()
        var manager = CLLocationManager()
        manager.delegate = self
        manager.desiredAccuracy = kCLLocationAccuracyBest

        let authorizationStatus = CLLocationManager.authorizationStatus()
        switch authorizationStatus {
        case .Authorized:
            println("authorized")
        case .AuthorizedWhenInUse:
            println("authorized when in use")
        case .Denied:
            println("denied")
        case .NotDetermined:
            println("not determined")
        case .Restricted:
            println("restricted")
        }

        manager.requestWhenInUseAuthorization()
        manager.startUpdatingLocation()

    }

    func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {
        let location = locations[0] as CLLocation
        println("Latitude: \(location.coordinate.latitude). Longitude: \(location.coordinate.longitude).")
    }

    func locationManager(manager: CLLocationManager!, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
        switch status {
        case .Authorized:
            println("authorized")
        case .AuthorizedWhenInUse:
            println("authorized when in use")
        case .Denied:
            println("denied")
        case .NotDetermined:
            println("not determined")
        case .Restricted:
            println("restricted")
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }

}

The console only showed "not determined" once and nothing else. So I went to iPhone Simulator => Settings => Privacy => Location => My App. It showed me 3 options: "Never", "While Using the App", "Always". But nothing was selected.

回答1:

Problem solved. My manager was declared as local var inside viewDidLoad() method, but it should've been a class level property.

After I moved manager declaration out of viewDidLoad(), my app worked.

Not sure how exactly manager.requestWhenInUseAuthorization() work behind the scene and why exactly manager defined within viewDidLoad() not work. Hope someone who knows this detail enlighten me.

回答2:

Setting these properties in the viewWillAppear instead of the viewDidLoad fixed it for me, thanks!

override func viewWillAppear(animated: Bool) {

    locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
    locationManager.requestWhenInUseAuthorization()
    locationManager.startUpdatingLocation()
  }

回答3:

I also faced the same problem. I have added two keys together in info.plist.

NSLocationWhenInUseUsageDescription key is supported in iOS 8.0 and later. If your Info.plist file includes both this key and the NSLocationUsageDescription key, the system uses this key and ignores the NSLocationUsageDescription key.

Rearranged the code:

let locationManager: CLLocationManager = CLLocationManager()
  let authorizationStatus = CLLocationManager.authorizationStatus()

override func viewDidLoad() {
    super.viewDidLoad()

    locationManager.delegate = self
    if(authorizationStatus == .Denied)
    {
      print("DENIED")
      locationManager.requestWhenInUseAuthorization()
    }

  }
override func viewWillAppear(animated: Bool) {

    locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
    locationManager.requestWhenInUseAuthorization()
    locationManager.startUpdatingLocation()
  }

Clean the project and run again.

来源：https://stackoverflow.com/questions/27681951/requestwheninuseauthorization-not-work-in-ios-8-with-nslocationwheninuseusaged