Swift / Firebase：如何在创建帐户时将Facebook用户正确存储到Firebase数据库中？

我将updateChildValues放在正确的位置吗？它目前位于signInWithCredential中.我还必须执行FBSDKGraphrequest来获取我感兴趣的信息存储在我的firebase数据库中.

我的firebase的Auth选项卡显示身份验证正在运行：

但数据库没有更新：

func showLoginView() {
    let loginManager = FBSDKLoginManager()
    loginManager.logInWithReadPermissions(fbPermissions,fromViewController: self,handler: { (result:FBSDKLoginManagerLoginResult!,error:NSError!) -> Void in

        if ((error) != nil) {
            print("Error loggin in is \(error)")
        } else if (result.isCancelled) {
            print("The user cancelled loggin in")
        } else {
            // No error,No cancelling:
            // using the FBACcessToken,we get a Firebase token
            let credential = FIRFacebookauthprovider.credentialWithAccessToken(FBSDKAccessToken.currentAccessToken().tokenString)

            // using the credentials above,sign in to firebase to create a user session
            FIRAuth.auth()?.signInWithCredential(credential) { (user,error) in
                print("User logged in the firebase")

                // adding a reference to our firebase database
                let ref = FIRDatabase.database().referenceFromURL("https://project-12345.firebaseio.com/")

                // guard for user id
                guard let uid = user?.uid else {
                    return
                }

                // create a child reference - uid will let us wrap each users data in a unique user id for later reference
                let usersReference = ref.child("users").child(uid)

                // performing the Facebook graph request to get the user data that just logged in so we can assign this stuff to our Firebase database:
                let graphrequest : FBSDKGraphrequest = FBSDKGraphrequest(graPHPath: "me",parameters: ["fields": "id,name,email"])
                graphrequest.startWithCompletionHandler({ (connection,result,error) -> Void in

                    if ((error) != nil) {
                        // Process error
                        print("Error: \(error)")
                    } else {
                        print("fetched user: \(result)")

                        // Facebook users name:
                        let userName:NSString = result.valueForKey("name") as! NSString
                        self.usersName = userName
                        print("User Name is: \(userName)")
                        print("self.usersName is \(self.usersName)")

                        // Facebook users email:
                        let userEmail:NSString = result.valueForKey("email") as! NSString
                        self.usersEmail = userEmail
                        print("User Email is: \(userEmail)")
                        print("self.usersEmail is \(self.usersEmail)")

                        // Facebook users ID:
                        let userID:NSString = result.valueForKey("id") as! NSString
                        self.usersFacebookID = userID
                        print("Users Facebook ID is: \(userID)")
                        print("self.usersFacebookID is \(self.usersFacebookID)")
                    }
                })

                // set values for assignment in our Firebase database
                let values = ["name": self.usersName,"email": self.usersEmail,"facebookID": self.usersFacebookID]

                // update our databse by using the child database reference above called usersReference
                usersReference.updateChildValues(values,withCompletionBlock: { (err,ref) in
                    // if there's an error in saving to our firebase database
                    if err != nil {
                        print(err)
                        return
                    }
                    // no error,so it means we've saved the user into our firebase database successfully
                    print("Save the user successfully into Firebase database")
                })
            }
        }
    })
}

更新：

显然在10分钟左右之后,数据库被更新了空的Facebook数据…不知道为什么它需要这么长时间.这是一个截图：