ios - XCode 中的 tableView 正在返回包含来自数组的随机数据的单元格

问题描述

我正在 xcode 中制作一个简单的消息传递应用程序。表格视图填充有包含右视图和左视图的自定义单元格。当用户收到消息时，左视图被填充，当用户发送消息时，右视图被填充。

问题是在重新加载 tableView 后，有时我会看到单元格中填充了来自包含消息的数组的乱码数据。我不确定发生了什么。

我尝试过的事情：

我检查了存储在 Back4App 后端的消息文件，它们都包含正确的 csv 数据
我查看了我的细胞计数，它总是准确的
我已经在表格重新加载之前和重新加载之后打印了数组和单元格数据，并且数组中的数据都是正确的。
如果我留下消息 VC 并返回给它，所有消息都会正确显示，但是当我留在 VC 中并使用发送按钮发送消息时，数据会被打乱一点，并打印出我的 tableView 的奇怪组合

您可以看到底线未正确显示：显示错误的图像

这是我的聊天VC：

//
//  ChatViewController.swift
//  Glam
//
//  Created by Student on 11/14/20.
//  Copyright © 2020 Tucker Weibell. All rights reserved.
//

import UIKit
import Parse

class ChatViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
    
    @IBOutlet weak var tableView: UITableView!
    @IBOutlet weak var navTitle: UINavigationItem!
    var senders = [String]()
    var message = [String]()
    var state = [String]()
    @IBOutlet weak var textView: UITextView!
    @IBOutlet weak var myView: UIView!
    @IBOutlet weak var bottomConstraint: NSLayoutConstraint!
    
    var dataStringSender = ""
    var dataStringReciever = ""
    var senderName = ""
    
    
    override func viewDidLoad() {
        super.viewDidLoad()
        getData()
        navTitle.title = MessageCustomerViewController.GlobalVars.selectedItem
        
        
        NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardNotification), name: UIResponder.keyboardWillShowNotification, object: nil)
        
        let tap = UITapGestureRecognizer(target: self, action: #selector(dismissKeyboard))
        self.view.addGestureRecognizer(tap)
    }
    
    func getData() {
        let user = PFUser.current()
        let username = user?.username
        senderName = username!
        let query = PFUser.query()
        query?.whereKey("username", equalTo: username!)
        do {
            let result = try query?.findObjects()
            let file = result![0]["Messages"] as! PFFileObject
            do {
                let data = try file.getData()
                let string = String(decoding: data, as: UTF8.self)
                dataStringSender = string
                let cvsRows = string.components(separatedBy: "\n")
                for row in cvsRows {
                    var itemsRow = row.components(separatedBy: ",")
                    print(itemsRow)
                    itemsRow[2] = itemsRow[2].replacingOccurrences(of: "\r", with: "")
                    print(itemsRow)
                    if itemsRow[0] == MessageCustomerViewController.GlobalVars.selectedItem {
                        senders.append(itemsRow[0])
                        message.append(itemsRow[1])
                        state.append(itemsRow[2])
                    }
                }
            }
            catch {
                print(error.localizedDescription)
            }
            
        }
        catch {
            print(error.localizedDescription)
        }
        
        loadData()
    }
    
    
    @IBAction func sendMessage(_ sender: Any) {
        
        let query = PFUser.query()
        query?.whereKey("username", equalTo: MessageCustomerViewController.GlobalVars.selectedItem)
        do {
            let result = try query?.findObjects()
            if result?[0]["Messages"] != nil {
                let file = result![0]["Messages"] as! PFFileObject
                do {
                    let data = try file.getData()
                    let string = String(decoding: data, as: UTF8.self)
                    dataStringReciever = string
                }
                catch {
                    print(error)
                }
            }
            
        }
        catch {
            print(error)
        }
        
        dataStringSender = dataStringSender + "\n" + MessageCustomerViewController.GlobalVars.selectedItem + "," + textView.text + "," + "Sent"
        dataStringReciever = dataStringReciever + "\n" + senderName + "," + textView.text + "," + "Recieved"
        
        let dataSent = Data(dataStringSender.utf8)
        let dataRecieved = Data(dataStringReciever.utf8)
        //let fileSent: PFFileObject = PFFileObject(data: dataSent)!
        //let fileRecieved: PFFileObject = PFFileObject(data: dataRecieved)!
        
        
        let fileSent = PFFileObject(name: "message.csv", data: dataSent)
        
        let fileRecieved = PFFileObject(name: "message.csv", data: dataRecieved)
        
        let user = PFUser.current()
        user!["Messages"] = fileSent
        user?.saveInBackground()
        
        let newQuery = PFUser.query()
        newQuery?.whereKey("username", equalTo: MessageCustomerViewController.GlobalVars.selectedItem)
        do {
            let newResults = try newQuery?.findObjects()
            newResults![0]["Messages"] = fileRecieved
            newResults![0].saveInBackground()
        }
        catch {
            print(error)
        }
        clearData()
        getData()
        print("\n")
        print("\n")
        print(message)
        print("\n")
        print("\n")
        print(state)
        loadData()
        
    }
    
    func loadData() {
        self.tableView.reloadData()
    }
    
    func clearData() {
        message.removeAll()
        state.removeAll()
        senders.removeAll()
    }
    
    
    @objc func handleKeyboardNotification(notification: NSNotification) {
        if let keyboardFrame: NSValue = notification.userInfo![UIResponder.keyboardFrameEndUserInfoKey] as? NSValue {
            let keyboardRectangle = keyboardFrame.cgRectValue
            var height = keyboardRectangle.height
            height = height * -1
            bottomConstraint.constant = height + 85
        }
        
    }
    
    @objc func dismissKeyboard(sender: UITapGestureRecognizer) {
        bottomConstraint.constant = 0
        textView.resignFirstResponder()
    }
    
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return message.count
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        
            print([message[indexPath.row]])
    
            let cell = tableView.dequeueReusableCell(withIdentifier: "messagescell") as! MessagesCell
        
            if state[indexPath.row] == "Sent" {
                cell.sentText.text = message[indexPath.row]
                cell.sentView.backgroundColor = .clear
            }
            else {
                cell.recievedText.text = message[indexPath.row]
                cell.recievedView.backgroundColor = .clear
        }
        return cell
    }


}

标签： iosswiftxcodeswift3tableview

ios - XCode 中的 tableView 正在返回包含来自数组的随机数据的单元格

问题描述

解决方案

推荐阅读