AppDelegate does not conform to protocol 'GIDSignInDelegate' in Swift 3

Question

I'm trying to authenticate with Firebase using their Google Accounts by integrating Google Sign-In into app.

Using:

• Swift 3
• Xcode 8
• Firebase 3.11.1

I have implemented the two methods of GIDSignInDelegate in AppDelegate

// Sign-in flow has finished and was succcesful if error is nil:
func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!){
if let error = error {
    print(error.localizedDescription)
    return
}

guard let authentication = user.authentication else { return }
let credential = FIRGoogleAuthProvider.credential(withIDToken: authentication.idToken,
                                                      accessToken: authentication.accessToken)



// Finished disconnecting user from the app succesfully if error is nil:
func sign(_ signIn: GIDSignIn!, didDisconnectWithUser user: GIDGoogleUser!,
                withError error: Error!) {
        // Perform any operations when the user disconnects from app here.
        // ...
}

yet I am still faced with the compile issue:

AppDelegate does not conform to protocol 'GIDSignInDelegate'

Answer 1

It looks like you defined the methods of that protocol outside of the AppDelegate class, so they are just global functions, not methods.

You need to move them inside the } that closes AppDelegate (just above the first protocol method).

Tip : if you select all of the code in that file and press Ctrl+I Xcode will reindent your code which may make it easier to see what's going wrong.