在最小化的视图控制器中显示自定义单元格标签文本

Question

I'm minimizing my view controller, so it only deals with user interactions, and leaves data handling and manipulation to a separate data model class.

I don't get any custom cell label text values being displayed when I run the app. My cellForRowAt method is:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(forIndexPath: indexPath) as WordCustomCell

        let viewModel = WordViewModel(tableViewWord: tableViewWords[indexPath.row], selectedCell: selectedCells[indexPath.row], isEdit: isEditCell)
        cell.setUpWith(viewModel)
        return cell
    }

and my custom cell class is:

class WordCustomCell: UITableViewCell {

    @IBOutlet weak var englishWord: UILabel?
    @IBOutlet weak var foreignWord: UILabel?
    @IBOutlet weak var wordCheckmark: UIButton?
    @IBOutlet weak var buttonLeft: NSLayoutConstraint?

    var isCellTypeEditing:Bool = false
    var isConstraintUpdated:Bool = false
    let wordVC = WordsViewController()

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }

    override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: reuseIdentifier)
    }

    func setcellType(cellType:cellType) {
        switch cellType {
        case .cellTypeEditing:
            self.isCellTypeEditing = true
        case .cellTypeNonEditing:
            self.isCellTypeEditing = false

        }
    }

    override func updateConstraints() {
        super.updateConstraints()

        switch isCellTypeEditing {
        case true:
            print("isCellTypeEditing in updateConstraints in LanguageCustomCell is: \(isCellTypeEditing)")
            self.buttonLeft?.constant = 10
        case false:
            print("isCellTypeEditing in updateConstraints in LanguageCustomCell is: \(isCellTypeEditing)")
            self.buttonLeft?.constant = -30
        }
    }

    func setUpWith(_ viewModel: WordViewModel) {
        print("viewModel.englishWordTitle in setUpWith in WordCustomCell is: \(viewModel.englishWordTitle)")
        englishWord?.text = viewModel.englishWordTitle
        print("viewModel.foreignWordTitle in setUpWith in WordCustomCell is: \(viewModel.foreignWordTitle)")
        foreignWord?.text = viewModel.foreignWordTitle
        let selectedCell = viewModel.selectedCell
        let isEditCell = viewModel.isEdit

        if isEditCell == true {
            wordCheckmark?.isHidden = false
            UIView.animate(withDuration: 0.5, animations: {

                self.setcellType(cellType: .cellTypeEditing)

                self.setNeedsUpdateConstraints()
                self.wordVC.view.layoutIfNeeded()
                }, completion: { (true) in

            })
            print("if selectedCell in tableView(cellForRowAt) in LanguagesViewcontroller is: \(selectedCell)")
            if selectedCell{
                wordCheckmark?.setImage(UIImage.init(named: "checked"), for: UIControl.State.normal)
                //cell?.layer.backgroundColor = UIColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1.0).cgColor
            } else {
                wordCheckmark?.setImage(UIImage.init(named: "unchecked"), for: UIControl.State.normal)
            }
            wordCheckmark?.contentEdgeInsets = UIEdgeInsets.init(top: 5, left: 5, bottom: 5, right: 5)
            foreignWord?.text = ""
            wordVC.enableClear()
        } else {
            wordVC.tableView?.allowsMultipleSelection = false
            wordCheckmark?.isHidden = false
            wordCheckmark?.setImage(UIImage.init(named: "dot"), for: UIControl.State.normal)
            wordCheckmark?.contentEdgeInsets = UIEdgeInsets.init(top: 10, left: 10, bottom: 10, right: 10)
            setcellType(cellType: .cellTypeNonEditing)
            //cell?.layer.backgroundColor = UIColor.white.cgColor
            setNeedsUpdateConstraints()
            wordVC.view.layoutIfNeeded()
        }
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

I've also made a protocol that allows cell reuse, without having to hard code the cell reuse identifier in the view controller. Just to make new view controllers easier and simpler to add as the app develops in the future.

import Foundation
import UIKit

//1 protocol declaration
protocol Reusable {}
//2 protocol extension
extension Reusable where Self: UITableViewCell  {
    static var reuseIdentifier: String {
        return String(describing: self)
    }
}
//3 conforming to protocol
extension UITableViewCell: Reusable {}
//4 using generics to make code reusable
extension UITableView {
    func register<T: UITableViewCell>(_ :T.Type) {
        register(T.self, forCellReuseIdentifier: T.reuseIdentifier)
    }

    func dequeueReusableCell<T: UITableViewCell>(forIndexPath indexPath: IndexPath) -> T {
        guard let cell = dequeueReusableCell(withIdentifier: T.reuseIdentifier, for: indexPath) as? T else {
            fatalError("Could not deqeue cell")
        }
        return cell
    }
}

I'v done all the usual registering table view custom cells (as you can see in the view controller viewDidLoad), and I have all storyboard interface builder connections made. It worked before I started view controller minimization, and I haven't changed any storyboard options since it worked.

Answer 1

Solution after reviewing code:

When registering the WordCustomCell, you should specify the Nib name (WordsTableCell) as the cell is being loaded from the Nib.

In addition, you need to call super.init on the required init?(coder aDecoder: NSCoder)

Find below the changes that you need to make to your code.

WordsViewController.swift

// Register custom cell
tableView?.register(UINib(nibName: "WordsTableCell", bundle: nil), forCellReuseIdentifier: "WordCustomCell")
// tableView?.register(WordCustomCell.self)
tableView?.reloadData()

WordCustomCell.swift

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
}