Question

我是Swift和Firebase的新手。我正在尝试使用facebook登录来构建应用程序。我已经实现了一些代码并尝试学习本教程，但我不太了解登录如何保存并“知道”当前用户数据。所以我尝试在登录方法中实现此代码并保存用户ID NSUserDefaults.standardUserDefaults().setValue(result ["uid"], forKey: "uid")

和此：

 var REF_USER_CURRENT: Firebase {
    let userID = NSUserDefaults.standardUserDefaults().valueForKey("uid") as! String
    let currentUser = Firebase(url: "\(baseUrl)").childByAppendingPath("users").childByAppendingPath(userID)
    return currentUser!
}

登录后，它将移动到其他视图并显示用户名。我使用此代码检索用户名数据

   func displayName()  {

    FirebaseHelper.fbh.REF_USER_CURRENT.observeEventType(.Value, withBlock: {
        snapshot in
        let currentUser = snapshot.value.objectForKey("name") as! String
        self.currentUsername = currentUser
        self.facebookUserName.text = currentUser as String
        print("Username: \(currentUser)")
        }, withCancelBlock: { error in
            print(error.description)
    })

}

但是，每次登录时都会显示此错误致命错误：在展开“可选值”时意外发现nil 并突出显示REF_USER_CURRENT。我认为原因是因为它无法在NSUserDefault中保存uid。这是我的登录方法

func loginButton(loginButton: FBSDKLoginButton!, didCompleteWithResult result: FBSDKLoginManagerLoginResult!, error: NSError!) {

    if error != nil{
        print("Facebook login failed. Error \(error)")
    }else if result.isCancelled {
        print("Facebook login was cancelled")
    }else if result.grantedPermissions.contains("email"){
          let accessToken = FBSDKAccessToken.currentAccessToken().tokenString
        FirebaseHelper.fbh.REF_BASE.authWithOAuthProvider("facebook", token: accessToken, withCompletionBlock: { error, authData in

            if(error != nil){
                print("Login failed. \(error)")
            }else{
                print("Logged in! \(authData)")
                self.saveUserToFirebase(authData)
                print("User Saved Successfully! \(authData.uid)")
                self.processLogin(accessToken, authData: authData)
                let viewController:UIViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewControllerWithIdentifier("profileSetup") as! UIViewController
                self.presentViewController(viewController, animated: true, completion: nil)


            }

        })
    }

}

   func processLogin(accessToken: String, authData: FAuthData) {
    FirebaseHelper.fbh.REF_USER_CURRENT.childByAppendingPath(authData.uid).observeSingleEventOfType(.Value, withBlock: { snapshot in
        if snapshot.value is NSNull {
            print("fail")
        } else {
            print("no")
        }
    })
}


private func createUser(authData: FAuthData!){

    let displayName = authData.providerData["displayName"] as! String
    let email = authData.providerData["email"] as! String
    var imageUrl = ""

    if let url = authData.providerData["profileImageURL"] as? String {
        imageUrl = url
    }

    let request = FBSDKGraphRequest(graphPath: "me/picture", parameters: ["fields": "url", "redirect": false, "type": "large"], HTTPMethod: nil)
    request.startWithCompletionHandler { connection, result, facebookerror in

        if facebookerror != nil{
            print("Graph API Call failed. \(facebookerror)")
        }else{

            //let userData = (result as! NSDictionary).copy()

            let user = ["name": displayName, "email": email,"profilePicUrl": imageUrl]
            FirebaseHelper.fbh.createFirebaseUser(authData.uid, user: user)
            if facebookerror != nil{
                print("Error occured! \(facebookerror)")
            }else{
                print("User Saved Successfully! \(authData.uid) \(displayName)")
                NSUserDefaults.standardUserDefaults().setValue(result ["uid"], forKey: "uid")


            }
            self.facebookLoginBtn.hidden = true
        }
    }

}

我不明白NSUserdafult如何为当前用户工作，我是否需要在每个页面中编写任何代码来检查当前用户数据以检索数据？请修改我的代码以便更好地理解此问题。

Answer 1

如果目标是对用户进行身份验证，如果成功，则将其登录凭据存储在设备本地，这非常简单。

登录过程因提供商而异（确保在Firebase信息中心中已启用），但它们都具有相同的流量。

经过身份验证后，authData变量包含有关该特定用户的信息。 FAuthData对象上的uid属性是您唯一标识用户的方式。

let email = "dude@thing.com"
let pw = "password"

ref.authUser(email, pw) {
    error, authData in

    if error != nil {
        // eh, something went wrong, handle it

    } else {

       let myAppData = NSUserDefaults.standardUserDefaults()
       myAppData.setValue(auth.uid, forKey: "uid")
       myAppData.setValue(email, forKey: "email")
       myAppData.setValue(pw, forKey: "password")
    }
}

继续之后，您可能希望在Firebase中创建一个包含有关用户的其他信息的/ users节点

users
  uid_0
   name: "Pete"
   shoe_size: "13"
  uid_1
   name: "Larry"
   shoe_size: "2"

您可以在User Authentication部分的Firebase指南中找到有关此主题的更多信息，以及示例代码。

Facebook登录后的Firebase和Swift以及当前用户

1 个答案: