TableView 单元格重复 Swift

Question

So I'm making a GET request to my database and then adding each element from my array into a ViewModel, in var mainComment: Comments? . In my Custom Cell I'm assigning my label text to the ViewModel's mainComment.likes . I'm supposed to get one like for only my one cell but instead the one like is repeating for multiple cells. https://giphy.com/gifs/L2U6FALmxWx981nO44

struct Comments: Codable {
    var id:String?
    var likes:Int?
}

import UIKit
import Foundation

class CommentViewModel {
    var mainComment: Comments? 
}

//CommentVC
var comments:[CommentViewModel] = []

func loadComments(completion:@escaping(()->())) {
        guard let post_id = post_id else {
            return
        }
        let getComments = GETComments(id: post_id, path: "comments")
        getComments.getAllById { comments in
              self.comments = comments.map { comment in
                let ret = CommentViewModel()
                ret.mainComment = comment
        
                return ret
            }
            self.myTableView.reloadData()
            completion()
            }
        }
    }

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "MyCell", for: indexPath as IndexPath) as! CommentCell
        let item = comments[indexPath.item]
        cell.viewModel = item
     
        return cell
    }


class CommentCell {
var viewModel: CommentViewModel? {
        didSet {
            if let item = viewModel {
                if let numberOfLikes = item.mainComment?.likes {
                    self.numberOfLikes.text = "\(numberOfLikes)"
                }
          }
}

lazy var numberOfLikes:UILabel = {
        let label = UILabel()
        label.textAlignment = .center
        label.text = "0"
        return label
    }()

override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: reuseIdentifier)
        addSubview(numberOfLikes)
        commentLikesConstraints()
    }
func commentLikesConstraints() {
        numberOfLikes.translatesAutoresizingMaskIntoConstraints = false
        numberOfLikes.widthAnchor.constraint(equalToConstant: 60).isActive = true
        numberOfLikes.heightAnchor.constraint(equalToConstant: 30).isActive = true
        numberOfLikes.centerXAnchor.constraint(equalTo: likeBtn.centerXAnchor).isActive = true
        numberOfLikes.topAnchor.constraint(equalTo: likeBtn.bottomAnchor, constant: -5).isActive = true
    }

Answer 1

Since you're using mainComment and likes as optionals:

struct Comments: Codable {
    var id:String?
    var likes:Int?
}

You need to handle an else case (and probably also want an else case if viewModel is nil):

var viewModel: CommentViewModel? {
    didSet {
        if let item = viewModel {
            if let numberOfLikes = item.mainComment?.likes {
                self.numberOfLikes.text = "\(numberOfLikes)"
            } else {
                self.numberOfLikes.text = "0"
            }
        } else {
            // do what you need to do if viewModel is nil
        }
    }
}