App crashing when using Firebase Auth, reason: 'Default app has already been configured.'

Question

I\'m building my first iOS application, and I am using Firebase to handle authentication, database, etc. I added a sign up screen and used the following code to create a new

Answer 1

just in case someone else stumble upon this problem. when use firebase sdk with googleSignIn sdk. you only have to configure them once. either do [[GGLContext sharedInstance] configureWithError: &configureError]; or [FIRApp configure]

Answer 2

For Swift 4

Had the same problem with crashing. When trying to reference from Firebase with a .plist file.

(This fixed my problem.)

Try writing this outside of or within the viewDidLoad method:

1. var ref: DatabaseReference!

Then reference it within the viewDidLoad method:

2. Database.database().reference()

And now it's:

FirebaseApp.configure()

Instead.

Answer 3

You can call once in AppDelegate init method to configure.

override init() {
   // Firebase Init
   FIRApp.configure()
}