title: Showing alertview as soon as location service is disabled
body: <p>I'm making an iOS app which requires location services enabled. So as soon as my app is installed, it asks users to allow location service. Apparently, a lot of users press "Don't allow" and ended up having not working my iOS app. </p>
  
  <p>In my app, I input below lines of code:</p>
  
  <pre><code>  override func viewDidAppear(animated: Bool) {
          super.viewDidAppear(animated)
  
          if CLLocationManager.authorizationStatus() == CLAuthorizationStatus.Denied {
              self.locationAlert = UIAlertView(title: "Location Services Permission Needed", message: "Location service needs to be turned on to use Peek! Please press setting button below and turn the service on!", delegate: self, cancelButtonTitle: "Settings")
              locationAlert.show()
        }
      }
  
      extension ViewController: UIAlertViewDelegate {
          func alertView(alertView: UIAlertView, clickedButtonAtIndex buttonIndex: Int) {
              alertView.dismissWithClickedButtonIndex(buttonIndex, animated: true)
              UIApplication.sharedApplication().openURL(NSURL(string: UIApplicationOpenSettingsURLString)!)
          }
      }
  </code></pre>
  
  <p>The problem is that the alertview only shows up when you reopen the app. I want this alertview to show up as soon as users press "Don't allow location service" when they installed the app.</p>
  
  <p>Is there a way to make this action happen?</p>