ios - 如何将步进值传递给 ViewController？

Question

我有一个自定义单元格，它有 2 个标签，myLabel 和 numLabel，以及一个步进器。我在 Swift 文件和 XIB 文件中有我的自定义单元格。我希望当我单击步进器上的 + 或 - 按钮时，我的 numLabel 会随着步进器的值而变化。我不知道如何将步进值传递给我有 tableView 的 viewController。后来想将步进值保存到 CoreDate 我该怎么做？我只是一个初学者。谢谢你的帮忙。
MyCell.swift

import UIKit

class MyCell: UITableViewCell {
    
    static let identifier = "MyCell"
    
    static func nib() -> UINib {
        return UINib(nibName: "MyCell", bundle: nil)
    }
    
    public func configure(with name: String, number: String) {
        myLabel.text = name
        numLabel.text = number
    }
    
    @IBOutlet var myLabel: UILabel!
    @IBOutlet var numLabel: UILabel!
        
    

    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
    }
    
}

ViewController.swift

import UIKit

class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
    
    @IBOutlet var table: UITableView!

    override func viewDidLoad() {
        super.viewDidLoad()
        table.register(MyCell.nib(), forCellReuseIdentifier: MyCell.identifier)
        table.delegate = self
        table.dataSource = self
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 10
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: MyCell.identifier, for: indexPath) as! MyCell
        cell.configure(with: "Item 1", number: "1")
        return cell
    }


}

My Screen Shot

Answer 1

您可以使用“回调”闭包轻松完成此操作:

class MyCell: UITableViewCell {
    static let identifier: String = "MyCell"
    
    @IBOutlet var myStepper: UIStepper!
    @IBOutlet var numLabel: UILabel!
    @IBOutlet var myLabel: UILabel!

    // "callback" closure - set my controller in cellForRowAt
    var callback: ((Int) -> ())?
    
    public func configure(with name: String, number: String) {
        myLabel.text = name
        numLabel.text = number
    }

    @IBAction func stepperChanged(_ sender: UIStepper) {
        let val = Int(sender.value)
        numLabel.text = "\(val)"
        // send value back to controller via closure
        callback?(val)
    }

    static func nib() -> UINib {
        return UINib(nibName: "MyCell", bundle: nil)
    }

}

然后，在 cellForRowAt :

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: MyCell.identifier, for: indexPath) as! MyCell
    cell.configure(with: "Item 1", number: "1")
    
    // set the "callback' closure
    cell.callback = { (val) in
        print("Stepper in cell at \(indexPath) changed to: \(val)")
        // do what you want when the stepper value was changed
        //  such as updating your data array
    }

    return cell
}