以编程方式设置 TableViewCell

如何解决以编程方式设置 TableViewCell

所以我试图以编程方式创建一个 UITableViewCell 以在 UITableView 中使用。我已经完成了所有设置，但是当我加载模拟器时 tableview 是空的。见下面的代码：

class CustomTableViewCell: UITableViewCell {

    var firstText = UILabel()
    var secondText = UILabel()
    
    override func awakeFromNib() {
        
        super.awakeFromNib()
        // Initialization code
        firstText.translatesAutoresizingMaskIntoConstraints = false
        secondText.translatesAutoresizingMaskIntoConstraints = false
        
        contentView.addSubview(firstText)
        contentView.addSubview(secondText)
        
        NSLayoutConstraint.activate([
                firstText.centerXAnchor.constraint(equalTo: contentView.centerXAnchor),firstText.centerYAnchor.constraint(equalTo: contentView.centerYAnchor),firstText.heightAnchor.constraint(equalToConstant: 50),firstText.widthAnchor.constraint(equalToConstant: 50)
            ])
        
    }
    

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

        // Configure the view for the selected state
    }
}

然后是 UITableViewDataSource：

func tableView(_ tableView: UITableView,cellForRowAt indexPath: IndexPath)  -> UITableViewCell {

        let person = people[indexPath.row]
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell",for: indexPath) as! CustomTableViewCell
        let name = person.value(forKeyPath: "name") as? String
        let age = person.value(forKeyPath: "age") as? String
    
        cell.firstText.text = name
        cell.secondText.text = age
        
        return cell


    }

完整的视图控制器：

class ViewController: UIViewController,UITableViewDelegate {

    var names : [String] = []
    
    var people: [NSManagedobject] = []
    
    let TableView = UITableView() // view
    
    override func loadView() {
        super.loadView()
        setupComponents()
        setupTableView()
        TableView.delegate = self
        TableView.dataSource = self
        TableView.register(CustomTableViewCell.self,forCellReuseIdentifier: "cell")
        names = ["Samantha","Jacob","Justin"]
      }
    
    func setupComponents() {
        self.title = "Core Data"
        let addButton: UIBarButtonItem = UIBarButtonItem(title: "Add",style: .done,target: self,action: #selector(addTap))
        self.navigationItem.rightBarButtonItem = addButton
        guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {return}
        let fetchRequest =  NSFetchRequest<NSManagedobject>(entityName: "Person")
        let managedContext = appDelegate.persistentContainer.viewContext
         //3
          do {
            people = try managedContext.fetch(fetchRequest)
           } catch let error as NSError {
               print("Could not fetch. \(error),\(error.userInfo)")
          }
    }
    
    func setupTableView() {
        view.addSubview(TableView)
        TableView.translatesAutoresizingMaskIntoConstraints = false
        TableView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
        TableView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
        TableView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
        TableView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
      }
    
    @objc func addTap() {
        let alert = UIAlertController(title: "New Friend",message: "Add the name of your friend",preferredStyle: .alert)
        let saveAction = UIAlertAction(title: "Add Now",style: .default) { [uNowned self] action in

            guard let textField = alert.textFields?.first,let nametoSave = textField.text else { return }
            let secondTextField = alert.textFields![1]
            let age = secondTextField.text
            let ageInt = Int(age!)
            self.save(name: nametoSave,age: ageInt!)
            self.TableView.reloadData()
          }

          let cancelAction = UIAlertAction(title: "Cancel",style: .cancel)

          alert.addTextField()
          alert.addTextField()
          alert.addAction(saveAction)
          alert.addAction(cancelAction)
          present(alert,animated: true)
    }
    
    func save(name: String,age: Int) {

        guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {return}

        // 1
        let managedContext = appDelegate.persistentContainer.viewContext

        // 2
        let entity = NSEntityDescription.entity(forEntityName: "Person",in: managedContext)!

        let person = NSManagedobject(entity: entity,insertInto: managedContext)

        // 3
        person.setValue(name,forKeyPath: "name")
        person.setValue(age,forKeyPath: "age")

        // 4
        do {
            try managedContext.save()
            people.append(person)
        } catch let error as NSError {
            print(error.userInfo)
        }
        
        print("People",people)
    }

}

extension ViewController: UITableViewDataSource {

    func tableView(_ tableView: UITableView,numberOfRowsInSection section: Int) -> Int {
            return people.count
        }

    func tableView(_ tableView: UITableView,for: indexPath) as! CustomTableViewCell
        let name = person.value(forKeyPath: "name") as? String
        let age = person.value(forKeyPath: "age") as? String
    
        cell.firstText.text = name
        cell.secondText.text = age
        
        return cell


    }
}

name 和 age 都是有效且有效的，返回的结果并非如此。