signInSilently() generates an error code=-4

Question

I\'m having this case where the GIDSignIn.sharedInstance().signInSilently() is returning an error:

Error Domain=com.google.GIDSignIn Code=-4 \"The op

Answer 1

Please refer my answer from Saving the current GIDGoogleUser instead of signing in on every launch

you should conform the GIDSignInUIDelegate protocol without implementing the methods.

signInWillDispatch:error: 
signIn:presentViewController:
signIn:dismissViewController:

It will fix your error -4.