我正在尝试使用 Firebase 和 Facebook 登录并且它正在工作,但是当 Facebook 页面打开并且您在不登录的情况下关闭它时会抛出错误并说"致命错误:在解开可选值时意外发现 nil"突出显示为导致错误的行是let credential
....这是我的代码:
// Login button is pressed
func loginButton(loginButton: FBSDKLoginButton!, didCompleteWithResult result: FBSDKLoginManagerLoginResult!, error: NSError!) {
if let error = error {
print(error.localizedDescription)
} else {
let credential = FIRFacebookAuthProvider.credentialWithAccessToken(FBSDKAccessToken.currentAccessToken().tokenString)
FIRAuth.auth()?.signInWithCredential(credential) { (user, error) in
if let error = error {
print(error.localizedDescription)
} else {
self.performSegueWithIdentifier("loginSegue", sender: self)
print("Login complete")
}
}
}
}
有人可以帮我吗?谢谢
您还需要检查您是否有用户,或者用户是否取消了注册
if let user = user {
} else {
print("Uh oh. The user cancelled the Facebook login."))
}