Firebase Google SignIn每次都会询问权限

Question

I have implemented a Google SignIn with Firebase in my iOS app, following the Firebase guide. The problem is that every time I test the login, it always asks for permissions.

Here is the code of AppDelegate involved in Google SignIn:

class AppDelegate: UIResponder, UIApplicationDelegate, GIDSignInDelegate {

    var window: UIWindow?


    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]? = nil) -> Bool {
        // Override point for customization after application launch.
        FIRApp.configure()

        GIDSignIn.sharedInstance().clientID = FIRApp.defaultApp()?.options.clientID
        GIDSignIn.sharedInstance().delegate = self


        return true
    }

    func application(_ app: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any] = [:]) -> Bool {
        return GIDSignIn.sharedInstance().handle(url, sourceApplication: options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String, annotation: options[UIApplicationOpenURLOptionsKey.annotation])
    }

    func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) {

        if let error = error {
            print(error.localizedDescription)
            return
        }


        print("Logged in with Google successfull")


        // ... Firebase authentication ...

    }
}

And here the code of View Controller with GIDSignInButton:

import UIKit

class IntroViewController: UIViewController, GIDSignInUIDelegate {


    @IBOutlet weak var signInButton: GIDSignInButton!


    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        GIDSignIn.sharedInstance().uiDelegate = self
        signInButton.style = .wide
    }


}

I've searched a lot on the web but found nothing... So, how can I prevent to ask for permission every time?

Answer 1

I believe this is working as intended. The issue is that you're signing out the user when you're testing your app, and the Google Sign-in library makes the assumption that if a user has explicitly signed out of your app, it should ask that user for permission again before signing that user in.

If you don't explicitly sign out the user, both signIn() calls and signInSilently() calls should succeed without displaying any kind of sign-in screen.

Answer 2

I'm not entirely sure what you're asking. Do you want to check if the user is already signed in with their Google account?

if (GIDSignIn.sharedInstance().hasAuthInKeychain()) {
    // user is signed in
} else {
    // show login
}

Answer 3

You can override the problem in this way: You have to store in your internal database your currentID and when you open your app you get currentID and consequently you get all info for your user. I had the same problem with the Facebook Login and I solved with this issue. Good job

Answer 4

You can try signing in the user silently, But you will have to make sure wether or not if GIDAuthentication properties are already available to you or not such as - idToken , accessToken ..etc

Then just call for

signIn.signInSilently()

assuming that signIn is the parameter of type GIDSignIn

look for - (void) signInSilently in :- Google Docs

Answer 5

On successful google sign-in, Authentication firebase user worked for me, I used following code,

func signIn(signIn: GIDSignIn!, didSignInForUser user: GIDGoogleUser!, withError error: NSError?) {
    if error != nil {
        return
    }
    let authentication = user.authentication
    let credential = FIRGoogleAuthProvider.credentialWithIDToken(authentication.idToken,
                                                                 accessToken: authentication.accessToken)
    FIRAuth.auth()?.signInWithCredential(credential) { (user, error) in


        }

    }
}

Answer 6

According to Firebase official documentation, you should add the following function in AppDelegate:

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

And, if you want this to work in iOS 8 and less, you should add the function you already have:

func application(application: UIApplication,
  openURL url: NSURL, sourceApplication: String?, annotation: AnyObject?) -> Bool {
    var options: [String: AnyObject] = [UIApplicationOpenURLOptionsSourceApplicationKey: sourceApplication,
                                        UIApplicationOpenURLOptionsAnnotationKey: annotation]
    return GIDSignIn.sharedInstance().handleURL(url,
        sourceApplication: sourceApplication,
        annotation: annotation)
}

You can try adding both functions (As suggested by Firebsae), and see if this fixes the error. I'm not sure if this will gonna solve it, but at least is an improvement to the GID feature.

EDIT: Source: https://firebase.google.com/docs/auth/ios/google-signin