When the user is signing in / up using Apple Sign In is there a way to determine whether the user already signed up once using Apple Sign In to this app or it is his first time ( If the app in Apps Using Apple ID list in iPhone Settings )?
I want to know whether I need to sign in the user in the server side or continue to sign up flow after
func authorizationController(controller: ASAuthorizationController, didCompleteWithAuthorization authorization: ASAuthorization)
is called.
CodePudding user response：
You can check for existing login details on app launch using the app delegate:
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
let appleIDProvider = ASAuthorizationAppleIDProvider()
appleIDProvider.getCredentialState(forUserID: KeychainItem.currentUserIdentifier) { (credentialState, error) in
switch credentialState {
case .authorized:
break // The Apple ID credential is valid.
case .revoked, .notFound:
// The Apple ID credential is either revoked or was not found, so show the sign-in UI.
DispatchQueue.main.async {
self.window?.rootViewController?.showLoginViewController()
}
default:
break
}
}
return true
}