swift - 如何快速使按钮成为 IBOutlet 和 IBAction

Question

我有一个按钮，当我的计时器在 Xcode 中结束时我想禁用它，但要禁用按钮它需要一个 socket 。但是，我需要它是一个 Action ，因为它是一个重要的按钮。

代码:

import UIKit

class ViewController: UIViewController {

    var count = 0
    var timer = 60
    var highScore = 0

    @IBOutlet weak var output: UILabel!
    @IBOutlet weak var timerText: UILabel!
    @IBOutlet weak var scoreText: UILabel!
    @IBOutlet weak var highscoreText: UILabel!

    @IBAction func buttonOne(_ sender: Any) {
        count += 1
        output.text = String(count)
    }

    @IBAction func StartButton(_ sender: Any) {
        Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: Selector(("updateCounting")), userInfo: nil, repeats: true)
    }

    @objc func updateCounting(){
        if timer > 0 {
        timer -= 1
        timerText.text = String(timer)
        } else {
            buttonOneOutlet.isEnabled = false
            timerText.text = "Time up!"
            scoreText.text = "Score: " + String(count)
            if count > highScore {
                highScore = count
                highscoreText.text = String(count)
            } else {
                highscoreText.text = String(highScore)
            }
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }


}

Answer 1

我认为您混淆了 IBOutlet 和 IBAction。

其实区别在于:

"You need to specify IBAction for methods that will be used in Interface Builder and IBOutlet for objects that will be used in Interface Builder"

( Source - StackOverflow )

---

我稍微更改了您的代码，从 buttonOneOutlet (IBOutlet) 和 buttonOne (IBAction) 开始。

我添加了一个名为 buttonOne 的 IBOutlet 并将您的 IBActions 重命名为 buttonOneTouched 和 startButtonTouched。 Here您可以在 Swift 中找到一些关于命名约定的文档。

此外，我添加了一个名为 timerObject 的变量，这样您就可以保留对正在运行的计时器的引用，并在以后对它进行 invalidate()。否则计时器将永远运行。

这是更新后的代码:

import UIKit
class ViewController: UIViewController {

    var count = 0
    var timer = 60
    var highScore = 0
    // new timer object declared here
    var timerObject = Timer()

    // new IBOutlet object declared here
    @IBOutlet weak var buttonOne: UIButton!
    @IBOutlet weak var output: UILabel!
    @IBOutlet weak var timerText: UILabel!
    @IBOutlet weak var scoreText: UILabel!
    @IBOutlet weak var highscoreText: UILabel!

    // renamed the function to 'buttonOneTouched' (it was 'buttonOne')
    @IBAction func buttonOneTouched(_ sender: Any) {
        count += 1
        output.text = String(count)
    }

    // renamed the function to 'startButtonTouched' (it was 'StartButton')
    @IBAction func startButtonTouched(_ sender: Any) {
        timerObject = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: Selector(("updateCounting")), userInfo: nil, repeats: true)
    }

    @objc func updateCounting() {
        if timer > 0 {
            timer -= 1
            timerText.text = String(timer)
        } else {
            // added step to invalidate the running timer loop
            timerObject.invalidate()
            // replaced 'buttonOneOutlet' with 'buttonOne'
            buttonOne.isEnabled = false
            timerText.text = "Time up!"
            scoreText.text = "Score: " + String(count)
            if count > highScore {
                highScore = count
                highscoreText.text = String(count)
            } else {
                highscoreText.text = String(highScore)
            }
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }
}