在 View Controller 完成时传回多个变量

Question

如何在不使用结构或类的情况下在 View Controller 完成时传递多个传回多个变量？这是我的有效代码：

class TimerViewController: UIViewController {


//DELETED UNIMPORTANT CODE

    @IBAction func editTimerButtonPresed(_ sender: UIButton) {
        self.performSegue(withIdentifier: "goToEditTimer", sender: self)

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "goToEditTimer" {
            let destinationVC = segue.destination as! EditTimerViewController
            destinationVC.duration = Int(myTimer.totalTime)
            destinationVC.timerName = myTimer.timerName
            destinationVC.completion = { [weak self] duration in
                        DispatchQueue.main.async {
                            self?.myTimer.totalTime = Double(duration!)
                            self?.timerLabel.text = String(duration!)
                            self?.timer.invalidate()
                        }
            }
        }
    }
}

_

class EditTimerViewController: UIViewController, UITextFieldDelegate {

    var duration: Int? //timer duration is passed from Timer
    var timerName: String?
    public var completion: ((Int?) -> Void)?

//DELETED UNIMPORTANT CODE

    @IBAction func savePressed(_ sender: UIButton) {
        timerName = timerNameField.text
        let timerData = [duration!, timerName] as [Any]
        completion?(timerData)
        self.dismiss(animated: true, completion: nil)

    }
}

但现在我想传递对 duration 和 timerName 所做的更改。

更新

按照@koen 的建议，我尝试将两个变量放在一个元组中，但出现了一个我无法理解的错误。

在这里，我将 timerData 声明为 (Int?, String?) 的元组，但出现预期参数类型为 Int?:

的错误

class EditTimerViewController: UIViewController, UITextFieldDelegate {

    var duration: Int? //timer duration is passed from Timer
    var timerName: String?    
    public var completion: ((Int?) -> Void)?

//DELETED UNIMPORTANT CODE

    @IBAction func savePressed(_ sender: UIButton) {
        timerName = timerNameField.text
        var timerData = (duration: duration, name: timerName)
        completion?(timerData)   //ERROR Cannot convert value of type '(duration: Int?, name: String?)' to expected argument type 'Int?'
        self.dismiss(animated: true, completion: nil)    
    }
}

但我收到以下字符串的错误消息：

self?.myTimer.totalTime = Double(timerData[0]!)
self?.timerLabel.text = String(timerData[1]!)

但我没有在父级声明它 VC:

class TimerViewController: UIViewController {


//DELETED UNIMPORTANT CODE
//timerData was not declared

    @IBAction func editTimerButtonPresed(_ sender: UIButton) {
        self.performSegue(withIdentifier: "goToEditTimer", sender: self)

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "goToEditTimer" {
            let destinationVC = segue.destination as! EditTimerViewController
            destinationVC.duration = Int(myTimer.totalTime)
            destinationVC.timerName = myTimer.timerName
            let timerData = [destinationVC.duration!, destinationVC.timerName!] as [Any]
            destinationVC.completion = { [weak self] timerData in //if I check timerData it is described as Declaration let timerData: Int? Declared In TimerViewController.swift
                        DispatchQueue.main.async {
                            self?.myTimer.totalTime = Double(timerData.duration) //ERROR  Argument passed to call that takes no arguments + ERROR Value of type 'Int?' has no member 'duration'
                            self?.timerLabel.text = String(timerData.name) //ERROR  Argument passed to call that takes no arguments + ERROR Value of type 'Int?' has no member 'duration'
                            self?.timer.invalidate()
                        }
            }
        }
    }
}

Answer 1

我不得不改变

public var completion: ((Int?) -> Void)?

至

public var completion: (((duration: Int?, name: String?)) -> Void)?

在 View Controller 完成时传回多个变量

pass back multiple variables on View Controller completion

segue

swift

dispatch-queue