Data is uploaded but can't retrieve to the list Firebase

I upload the data to the database successfully but I can't see the data in the cell of the list of the table view. I can't see even one cell. Please see my code of the table view controller :

   var tutsArray = [Tutorials]()
    var userArray = [Users]()
    var dataBaseRef: DatabaseReference! {
        return Database.database().reference()
    }
    override func viewDidLoad() {
        super.viewDidLoad()
        let ref = Database.database().reference()
        ref.observe(.value, with: { snapshot in
            /
            var newItems: [Tutorials] = []
           
            /
            for item in snapshot.children {
                /
                let tut = Tutorials(snapshot: item as! DataSnapshot)
                newItems.append(tut)
            }
           
            /
            self.tableView.reloadData()
        })
    }
   
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        let ref = Database.database().reference()
        ref.queryOrdered(byChild: "tuts").observe(.value, with: { snapshot in
            /
            var newItems: [Tutorials] = []
           
            /
            for item in snapshot.children {
                /
                let tut = Tutorials(snapshot: item as! DataSnapshot)
                newItems.append(tut)
            }
           
            /
            self.tableView.reloadData()
        })
        loadData()
    }
   
    func loadData() {
        self.tutsArray.removeAll()
        let ref = Database.database().reference()
        ref.child("tut").observeSingleEvent(of: .value, with: { (snapshot) in
            if let todoDict = snapshot.value as? [String:AnyObject] {
               
               
            }
            self.tableView.reloadData()
           
        }) { (error) in
            print(error.localizedDescription)
        }
       
    }
    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        /
        return self.tutsArray.count
    }
   
   
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "sharesCell", for: indexPath) as! ArtTutsTableViewCell
       
        /
       
    /
        cell.tutName?.text = tutsArray[indexPath.row].tutName
        return cell
    }
   
    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        _ = self.tutsArray[indexPath.row]
       
        let tutorialViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "idTutorialViewController") as! ArtTutsViewController
       
    /
       
        showDetailViewController(tutorialViewController, sender: self)
       
    }
 
Data is uploaded but can't retrieve to the list Firebase
 
 
Q