通过从上到下滚动表格来刷新 UITable 内容

Posted 2023-02-27

【中文标题】通过从上到下滚动表格来刷新 UITable 内容

【英文标题】：Refresh UITable content by scrolling table from top to bottom

【发布时间】：2021-10-07 17:48:36

【问题描述】：

我正在使用 swift5 构建 ios 应用程序。 所以在我看来，我创建 TableView 来显示一些信息。当用户打开视图时，我调用 Web 服务来检索要在我的 TableView 中显示的数据。但我也希望用户可以像在普通应用程序中一样刷新表格的内容。

这是我的表格视图的代码：

extension HomeVC : UITableViewDataSource 
    
    func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        
        return self.arrListAll.count
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! homcell
        /*var arrList:[Result] = []
        if buttonTag == 0
            arrList = self.arrListPending
        else if buttonTag == 1
            arrList = self.arrListProcess
        else if buttonTag == 2
            arrList = self.arrListCompleted
        else if buttonTag == 3
            arrList = self.arrListRejected
        */
        
        let order = self.arrListAll[indexPath.row]
            let arrayArticoli = order.itemData
            var strOrder:String = ""
            for i in 0..<arrayArticoli.count 
                var prodotto = arrayArticoli[i]
                strOrder += "\(prodotto.itemQuantity) x \(prodotto.itemName)\n"
                //devo verificare che ingredient name abbia qualcosa
                if(prodotto.itemName != nil &&
                    prodotto.ingredientName != "" )
                    
                    var aggiunte = prodotto.ingredientName
                    var arr = aggiunte.components(separatedBy: ", ")
                    if(arr.count>0)
                        var cont = 0
                        for y in 0..<arr.count - 1 
                            strOrder += (arr[y]) + ", "
                            if(cont == 2)
                                cont = 0
                                strOrder += "\n"
                            
                            cont = cont + 1
                        
                        if(i < (arrayArticoli.count - 1))
                            strOrder += "\n"
                        
                        
                    
                
            
            var timeBooking:String? = order.timeBooking
            if ((timeBooking?.isEmpty) != nil)
                cell.lblTitlePrenotazione.text = "è una prenotazione, controlla l'orario \ndi prenotazione in fondo."
                cell.lblTitlePrenotazione.backgroundColor = UIColor.yellow
                cell.lbl_OrarioPrenotazione.text = "Prepara per le ore " + (timeBooking)!
                cell.lbl_OrarioPrenotazione.backgroundColor = UIColor.yellow
            else
                cell.lblTitlePrenotazione.text = ""
                cell.lbl_OrarioPrenotazione.text = ""
            
            cell.lblTitleOrderDetail.text = "DETTAGLIO ORDINE:"
            cell.lblId.text = "ID : \(order.id)"
            cell.lbl_Name.text = order.userName
            let formatter = DateFormatter()
            formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
            let date = formatter.date(from: order.dateTime)
            formatter.dateFormat = "dd/MM/yyyy HH:mm"
            cell.lbl_Date.text = "DATA : \(formatter.string(from: date!))"
            cell.lbl_Number.text = "Numero : \(order.mobile)"
            cell.lbl_OrderDetail.text = strOrder
            //cell.lbl_OrderDetail.sizeToFit();
            //cell.lbl_OrderDetail.adjustsFontSizeToFitWidth = false
            //cell.lbl_OrderDetail.lineBreakMode = .byTruncatingTail
            cell.lbl_OrderDetail.lineBreakMode = NSLineBreakMode.byWordWrapping

            cell.lbl_DeliveryCharge.text = "Consegna \(kCurrency):\(order.deliveryCoast)"
            let ordine = Double(order.totalOrder ?? "0.0")! + Double(order.deliveryCoast ?? "0.0")!
            cell.lbl_Total.text = "Totale \(kCurrency):\(ordine)"
           
            
            cell.lbl_Paynet.text = "Ordine\(kCurrency):\(order.totalOrder)"
            if(order.paymentType == "Cash")
                cell.lbl_PaymentType.text = "Pagamento in contanti :"
            else if(order.paymentType == "Card")
                cell.lbl_PaymentType.text = "Pagamento con carta :"
            
            
            cell.btn_messa.tag = indexPath.row
            cell.btn_messa.addTarget(self, action: #selector(goSendMessage), for: .touchUpInside)

            cell.btnccall.tag = indexPath.row
            cell.btnccall.addTarget(self, action: #selector(goReject), for: .touchUpInside)
            
            cell.btn_Wait.tag = indexPath.row
            cell.btn_Wait.addTarget(self, action: #selector(goAcceptMove), for: .touchUpInside)
            if(buttonTag == 0)
                if(order.status == self.st_pending)
                    cell.btn_Wait.setTitle("Accetta ordine",for: .normal)
                    cell.btn_Wait.isEnabled = true
                else if(order.status == self.st_driver_rejected)
                    cell.btn_Wait.setTitle("Ordine rifiutato dal Runner",for: .normal)
                    cell.btn_Wait.isEnabled = false
                
                
                cell.btn_Wait.backgroundColor = UIColor.systemOrange
            else if(buttonTag == 1)
                if(order.status == self.st_driver_accept)
                    cell.btn_Wait.setTitle("Ordine accettato dal Runner",for: .normal)
                    cell.btn_Wait.isEnabled = true
                else if(order.status == self.st_process)
                    cell.btn_Wait.setTitle("in Attesa che il Moover accetti",for: .normal)
                    cell.btn_Wait.isEnabled = false
                else if(order.status == self.st_way)
                    cell.btn_Wait.setTitle("in Consegna",for: .normal)
                    cell.btn_Wait.isEnabled = false
                
                cell.btn_Wait.backgroundColor = UIColor.systemOrange
                
            else if(buttonTag == 2)
                cell.btn_Wait.setTitle("Ordine Consegnato",for: .normal)
                cell.btn_Wait.backgroundColor = UIColor.systemOrange
                cell.btn_Wait.isEnabled = false
            else if(buttonTag == 3)
                cell.btn_Wait.setTitle("Ordine Cancellato",for: .normal)
                cell.btn_Wait.backgroundColor = UIColor.red
                cell.btn_Wait.isEnabled = false
            
        
        
        return cell
    
    
    func goHistoryOrder(indexRow indexRow: Int)
        let order = self.arrListAll[indexRow]
        if(order.status == self.st_driver_accept)
            let objVC = kStoryboardMain.instantiateViewController(withIdentifier: "HistoryDetailVC") as! HistoryDetailVC
            objVC.order = order
            self.navigationController?.pushViewController(objVC, animated: true)
        
    
    
    
    @objc func goAcceptMove(butt:UIButton)  
        let order = self.arrListAll[butt.tag]
        if(order.status == self.st_pending)
            cambiaStatoOrdine(strStatu: "Process", strId: order.id)
        else if(order.status == self.st_driver_accept)
            goHistoryOrder(indexRow: butt.tag)
        
        
    
    @objc func goSendMessage(butt:UIButton)  
        let order = self.arrListAll[butt.tag]
        let objVC = kStoryboardMain.instantiateViewController(withIdentifier: "UserChat") as! UserChat
        objVC.receiverId = order.userID
        objVC.userName = order.userName
        self.navigationController?.pushViewController(objVC, animated: true)
    
    @objc func goReject(butt:UIButton)  

    
    

现在当用户打开视图时，它可以显示这个视图：

现在如果用户从下到上滚动表格，表格显示使用其他顺序，但是当用户从上到下滚动表格并且表格到达第一个元素时，我想调用一个方法来获取所有新数据并刷新表格内容。

【参考方案1】：

您可以使用 UIRefreshControl（链接到 docs），使用它的简单方法如下：

func setupTableView() 
   //You can add tableView.delegate = self and
   // and tableView.dataSource = self here
   
   // And here is the code to setup the refresh control
   tableView.refreshControl = UIRefreshControl()
   tableView.refreshControl?.addTarget(self, action:
                                  #selector(handleRefreshControl),
                                  for: .valueChanged)


func handleRefreshControl() 
   //This method gets called when the user pulls to refresh on the table view so you can refresh the data source here and make sure to call .endRefreshing on the refresh control to stop the loading animation
 

现在在你的viewDidLoad 方法中确保调用setupTableView 方法。