title: Swift Google+ login GPPSignIn.sharedInstance().userID equals always nil
body: <p>I'm trying to implement Google+ login in iOS app using Swift language.</p>
  
  <p>My code looks like this:</p>
  
  <pre><code>var kClientId = "My Client ID from Dev Console"
  var signIn = GPPSignIn.sharedInstance()
  signIn.shouldFetchGooglePlusUser = true
  signIn.shouldFetchGoogleUserEmail = true
  signIn.shouldFetchGoogleUserID = true
  signIn.clientID = kClientId
  signIn.scopes = [kGTLAuthScopePlusLogin]
  signIn.delegate = self
  signIn.authenticate()
  </code></pre>
  
  <p>For test purposes I created a lable and wanted to change this to user email who logged in.</p>
  
  <pre><code>if (GPPSignIn.sharedInstance().userID != nil) {
      var user = GPPSignIn.sharedInstance().googlePlusUser
      userName.text = user.name.JSONString()
      if (user.emails != nil){
          userEmailLable.text = user.emails.first?.JSONString() ?? "no email"
      } else {
          userEmailLable.text = "no email"
      }
  } else {
      println("User ID is nil")
  }
  </code></pre>
  
  <p>After I click "Login" button Safari tab opens and I can enter my Google email and password and it asks permissions for certain things and after pressing Accept button it returns back to the application. My userEmailLable is not changed and it prints "User ID is nil" as an output. It happens all the time and there were not a single successful login.</p>
  
  <p>My Google frameworks are all fine, URLs are also correct, in Google Developer console are everything as it should be.</p>
  
  <p>AppDelegate.swift file includes this function also</p>
  
  <pre><code>func application(application: UIApplication, openURL url: NSURL, sourcApplication: String, annotation: AnyObject?) -&gt; Bool {
      return GPPURLHandler.handleURL(url, sourceApplication: sourcApplication, annotation: annotation)
  }
  </code></pre>
  
  <p>Anybody knows why is it doing so? Thanks!</p>