I logged google into the ios app. Now, how can I check if the user is registered, and if not, return him to the login page using Swift?

Question

As I wrote in the title of this question, I went through this tutorial https://developers.google.com/identity/sign-in/ios/sign-in and now I can log in to my application. based on his Google credentials.

While I am doing this, I have a class ViewController.swiftwith the following code:

class ViewController: UIViewController, GIDSignInUIDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()
        let background = CAGradientLayer().greenBlue()
        background.frame = self.view.bounds
        self.view.layer.insertSublayer(background, atIndex: 0)
        //GIDSignIn.sharedInstance().uiDelegate = self

        // Uncomment to automatically sign in the user.
        //GIDSignIn.sharedInstance().signInSilently()

    }

    override func viewDidAppear(animated: Bool) {
        super.viewDidAppear(animated)
        GIDSignIn.sharedInstance().uiDelegate = self

        GIDSignIn.sharedInstance().signInSilently()
    }

    @IBAction func didTapSignOut(sender: AnyObject) {
        GIDSignIn.sharedInstance().signOut()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func signInWillDispatch(signIn: GIDSignIn!, error: NSError!) {
        print("Nothing!")
    }

    // Present a view that prompts the user to sign in with Google
    func signIn(signIn: GIDSignIn!,
        presentViewController viewController: UIViewController!) {
            self.presentViewController(viewController, animated: true, completion: nil)
    }

    // Dismiss the "Sign in with Google" view
    func signIn(signIn: GIDSignIn!,
        dismissViewController viewController: UIViewController!) {
            self.dismissViewControllerAnimated(true, completion: nil)
    }
}

and in my class AppDelegate.swift I have:

class AppDelegate: UIResponder, UIApplicationDelegate, GIDSignInDelegate {

    var window: UIWindow?


    func application(application: UIApplication,
        didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
            // Initialize sign-in
            var configureError: NSError?
            GGLContext.sharedInstance().configureWithError(&configureError)
            assert(configureError == nil, "Error configuring Google services: \(configureError)")

            GIDSignIn.sharedInstance().delegate = self

            return true
    }

    // [START openurl]
    func application(application: UIApplication,
        openURL url: NSURL, sourceApplication: String?, annotation: AnyObject) -> Bool {
            return GIDSignIn.sharedInstance().handleURL(url,
                sourceApplication: sourceApplication,
                annotation: annotation)
    }
    // [END openurl]

    @available(iOS 9.0, *)
    func application(app: UIApplication, openURL url: NSURL, options: [String : AnyObject]) -> Bool {
        return GIDSignIn.sharedInstance().handleURL(url,
            sourceApplication: options[UIApplicationOpenURLOptionsSourceApplicationKey] as! String?,
            annotation: options[UIApplicationOpenURLOptionsAnnotationKey])
    }

    // [START signin_handler]
    func signIn(signIn: GIDSignIn!, didSignInForUser user: GIDGoogleUser!,
        withError error: NSError!) {
            if (error == nil) {
                print("Signed in!")
            } else {
                print("\(error.localizedDescription)")

            }
    }
    // [END signin_handler]

    // [START disconnect_handler]
    func signIn(signIn: GIDSignIn!, didDisconnectWithUser user:GIDGoogleUser!,
        withError error: NSError!) {
            // Perform any operations when the user disconnects from app here.
            // [START_EXCLUDE]
            NSNotificationCenter.defaultCenter().postNotificationName(
                "ToggleAuthUINotification",
                object: nil,
                userInfo: ["statusText": "User has disconnected."])
            // [END_EXCLUDE]
    }
}

My storyboard is as follows:

ViewController Google ( , - !), TabController ( ):

class TabController: UITabBarController {

    override func viewDidLoad() {
        super.viewDidLoad()
        let background = CAGradientLayer().greenBlue()
        background.frame = self.view.bounds
        self.view.layer.insertSublayer(background, atIndex: 0)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

:

Google . , - , (TabController). Google - , .

, - ViewController. - TabController. , ViewController - TabController ViewController. ?

, TabController initial view controller, ?

===== EDIT

Mac Bellingrath appDelegate.swift, :

func application(application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
        // Initialize sign-in
        var configureError: NSError?
        GGLContext.sharedInstance().configureWithError(&configureError)
        assert(configureError == nil, "Error configuring Google services: \(configureError)")

        GIDSignIn.sharedInstance().delegate = self

        /* check for user token */
        if GIDSignIn.sharedInstance().hasAuthInKeychain() {
            /* Code to show your tab bar controller */
            print("user is signed in")
            let sb = UIStoryboard(name: "Main", bundle: nil)
            if let tabBarVC = sb.instantiateViewControllerWithIdentifier("TabController") as? UITabBarController {
                window!.rootViewController = tabBarVC
            }
        } else {
            print("user is NOT signed in")
            /* code to show your login VC */
            let sb = UIStoryboard(name: "Main", bundle: nil)
            if let tabBarVC = sb.instantiateViewControllerWithIdentifier("ViewController") as? ViewController {
                window!.rootViewController = tabBarVC
            }
        }

        return true
}

, tabController tabController. - ViewController. , , , , if GIDSignIn.sharedInstance().hasAuthInKeychain() { if !GIDSignIn.sharedInstance().hasAuthInKeychain() { , if !GIDSignIn.sharedInstance().hasAuthInKeychain() { user is signed in, , - ...

Answer 1

Google, , GIDSignIn hasAuthInKeychain(), , , .

, AppDelegate

func application(application: UIApplication,didFinishLaunchingWithOptions                    launchOptions: [NSObject: AnyObject]?) -> Bool {

- :

GIDSignIn.sharedInstance().delegate = self
/* check for user token */
if GIDSignIn.sharedInstance().hasAuthInKeychain() {
/* Code to show your tab bar controller */
} else {
/* code to show your login VC */
}

, :

let sb = UIStoryboard(name: "Main", bundle: nil)
if let tabBarVC = sb.instantiateViewControllerWithIdentifier("MainTabBarVC") as? UITabBarController {
window.rootViewController = tabBarVC
}

* UITabBarController UITabBarController.

, . .

Answer 2

Mac Bellingrath .

, .

Objective-C, .

.

    // The authentication object for the current user, or |nil| if there is currently no logged in user.
    // Here you can get current user object
    GIDGoogleUser *googleUser = [[GIDSignIn sharedInstance] currentUser];

    if (googleUser) {
        // Get new token from google and send to server
        NSString *strToken = googleUser.authentication.idToken;
    }
    else {
        // present login screen here
        [self presentLoginScreen];
    }

Answer 3

let googleUser = GIDSignIn.sharedInstance().isCurrentUser

if googleUser != nil {
// Get new token from google and send to server
let strToken = googleUser.authentication.idToken
} else {
// present login screen here
presentLoginScreen()
}