Firebase数据库误读

Question

My data all of a sudden stopped showing up for my username. Is there something very odd about this or am I just misreading my code. It was working before, but now all of a sudden it has stopped outputting the username.

{
   "rules": {
  "Users":{
     ".read": "true",
     ".write": "true"
},
  "general_room" : {
    ".read": "true",
     ".write": "true"
  }
    }
}



import UIKit
import Foundation
import Firebase
import FirebaseDatabase
import FirebaseStorage
import AlamofireImage
import Alamofire

struct postStruct {
    let username : String!
    let message : String!
    let photoURL : String!
    let timeStamp: String!
}



class GeneralChatroom: UIViewController, UITableViewDataSource, UITableViewDelegate, UITextFieldDelegate {

    @IBOutlet weak var messageTextField: UITextField!
    @IBOutlet weak var tableView: UITableView!



    var generalRoomDataArr = [postStruct]()


    override func viewDidLoad() {
        super.viewDidLoad()


        //TableView Cell word wrap (Dynamic Text)
        self.tableView.dataSource = self
        self.tableView.delegate = self
        self.tableView.estimatedRowHeight = 78
        self.tableView.rowHeight = UITableViewAutomaticDimension






        let ref = FIRDatabase.database().reference()
        //let userID = FIRAuth.auth()?.currentUser?.uid


        ref.child("general_room").queryOrderedByKey().observe(.childAdded, with: {snapshot in

            let snapDict = snapshot.value as? NSDictionary
            let message = snapDict?["Message"] as? String ?? ""
            let username = snapDict?["Username"] as? String ?? ""
            let firebaseUserPhotoURL = snapDict?["photo_url"] as? String ?? ""

            print("username: " + username)
            print("message: " + message)

            //Time String from Firbase Database
            let timeString = snapDict?["time_stamp"] as? String ?? "2017-03-06 00:20:51"

            //timeAgoSinceDate - Format and call function to recieve time of post
            let dateFormatter = DateFormatter()
            dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
            let timeStampDate = dateFormatter.date(from: timeString)
            let timeStamp = timeAgoSinceDate(date: timeStampDate!, numericDates: false)


            //Assign array values
            self.generalRoomDataArr.insert(postStruct(username: username, message: message, photoURL: firebaseUserPhotoURL, timeStamp: timeStamp), at: 0)
            self.tableView.reloadData()


        })

    }


    @IBAction func backButtonPressed(_ sender: UIButton) {
        self.performSegue(withIdentifier: "BackToRoom", sender: nil)
    }


    //Message Send button is pressed data uploaded to firebase
    @IBAction func sendButtonPressed(_ sender: UIButton) {



        //If a character exists will be uploaded to firebase
        if ((messageTextField.text?.characters.count)! > 0) {

        let message : String = self.messageTextField.text!
        UploadGeneralChatRoom(message: message) //upload to general_room
        self.messageTextField.text = nil
        messageTextField.resignFirstResponder()//Quit keyboard

        self.tableView.reloadData() //Reload tableView
        //UploadUserData() //Update Rank in database

        }


    }








    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return generalRoomDataArr.count // your number of cell here
    }




    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {


        let cell = tableView.dequeueReusableCell(withIdentifier: "cell")

        //Transform Data From ^ to load at the bottom
        tableView.transform = CGAffineTransform (scaleX: 1,y: -1);
        cell?.contentView.transform = CGAffineTransform (scaleX: 1,y: -1);
        cell?.accessoryView?.transform = CGAffineTransform (scaleX: 1,y: -1);


//        tableView.backgroundColor = UIColor.white
//        tableView.layer.cornerRadius = 3.0
//        tableView.layer.masksToBounds = false
//        tableView.layer.shadowColor = UIColor.black.withAlphaComponent(0.2).cgColor
//        tableView.layer.shadowOffset = CGSize(width: 0, height: 0)
//        tableView.layer.shadowOpacity = 0.8




//        cell?.contentView.backgroundColor = UIColor.clear
//        
//        let whiteRoundedView : UIView = UIView(frame: CGRect(x: 10, y: 8, width: self.view.frame.size.width - 20, height: 120))
//        
//        whiteRoundedView.layer.backgroundColor = CGColor(colorSpace: CGColorSpaceCreateDeviceRGB(), components: [1.0, 1.0, 1.0, 0.9])
//        whiteRoundedView.layer.masksToBounds = false
//        whiteRoundedView.layer.cornerRadius = 3.0
//        whiteRoundedView.layer.shadowOffset = CGSize(width: 0, height: 0)
//        whiteRoundedView.layer.shadowOpacity = 0.2
//        
//        cell?.contentView.addSubview(whiteRoundedView)
//        cell?.contentView.sendSubview(toBack: whiteRoundedView)
//        






//

        //Set username label to display username
        let usernameLabel = cell?.viewWithTag(1) as! UILabel
        usernameLabel.text = generalRoomDataArr[indexPath.row].username


        //Set message label to display message
        let messageLabel = cell?.viewWithTag(2) as! UILabel
        messageLabel.text = generalRoomDataArr[indexPath.row].message
        messageLabel.numberOfLines = 0

        //initialize UI Profile Image
        let imageView = cell?.viewWithTag(3) as! UIImageView

        //Make Porfile Image Cirlce
        imageView.layer.cornerRadius = imageView.frame.size.width/2
        imageView.clipsToBounds = true

        //Set timeStampLabel to current time AGO
        let timeStampLabel = cell?.viewWithTag(4) as! UILabel
        timeStampLabel.text = generalRoomDataArr[indexPath.row].timeStamp
        timeStampLabel.numberOfLines = 0

        //Loading and change of Usesrs profile image on chat cell
        let userProfileChatImage = generalRoomDataArr[indexPath.row].photoURL

        //Load profile image(on cell) with URL & Alamofire Library
        let downloadURL = NSURL(string: userProfileChatImage!)
        imageView.af_setImage(withURL: downloadURL as! URL)

        // your cell coding
        return cell!
    }




    //                      KeyBoard (move text box above keyboard)




    // Start Editing The Text Field
    func textFieldDidBeginEditing(_ messageTextField: UITextField) {
        moveTextField(messageTextField, moveDistance: -250, up: true)
    }

    // Finish Editing The Text Field
    func textFieldDidEndEditing(_ messageTextField: UITextField) {
        moveTextField(messageTextField, moveDistance: -250, up: false)
    }

    // Hide the keyboard when the return key pressed
    func textFieldShouldReturn(_ messageTextField: UITextField) -> Bool {
        messageTextField.resignFirstResponder()
        return true
    }

    // Move the text field in a pretty animation!
    func moveTextField(_ messageTextField: UITextField, moveDistance: Int, up: Bool) {
        let moveDuration = 0.3
        let movement: CGFloat = CGFloat(up ? moveDistance : -moveDistance)

        UIView.beginAnimations("animateTextField", context: nil)
        UIView.setAnimationBeginsFromCurrentState(true)
        UIView.setAnimationDuration(moveDuration)
        self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)
        UIView.commitAnimations()
    }


}//END CLASS

Answer 1

Preface: I can't make a simple comment yet because of rep. Checking the auth rules is important as Ro4ch mentioned. However, you could verify that the snapshot.key value is the same as the one on your Firebase console.

I'm going to assume that Kebtfc... is a child of general_room . If this is the case. then that snapshot would be an array of user snapshots correct? You would need to parse it as such.