为什么Google登录无法在设备上运行？

Question

当我在模拟器中使用此代码时 - 它完美运行：

// Present a view that prompts the user to sign in with Google
func signIn(signIn: GIDSignIn!,
            presentViewController viewController: UIViewController!) {
    self.presentViewController(viewController, animated: true, completion: nil)
}

// Dismiss the "Sign in with Google" view
func signIn(signIn: GIDSignIn!,
            dismissViewController viewController: UIViewController!) {
    self.dismissViewControllerAnimated(true, completion: nil)
}

func signIn(signIn: GIDSignIn!, didSignInForUser user: GIDGoogleUser!,
            withError error: NSError!) {
    if (error == nil) {
        // Perform any operations on signed in user here.
        let accessToken = user.serverAuthCode // Safe to send to the server

        print("AAA \(accessToken)")
    } else {
        print("\(error.localizedDescription)")
    }
}

但它在真实设备中不起作用。当我点击＆＃34;允许＆＃34;按钮，它会刷新页面并将我转发到google.com网站。

什么问题？