Question

我按照stackoverflow中显示的答案来实现倒数计时器。为标签设置文本时，计时器文本不会闪烁（完美地工作）。

当为按钮设置相同的文本时，每次设置标题时它都会闪烁。如何避免按钮文字闪烁？

@IBOutlet weak var countDownTimer: UILabel!
@IBOutlet weak var countDownTimerButton: UIButton!
var count = 120

override func viewDidLoad() {
    super.viewDidLoad()

    var _ = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(update), userInfo: nil, repeats: true)
    // Do any additional setup after loading the view.
}


func update() {

    if(count > 0){
        let minutes = String(count / 60)
        let seconds = String(count % 60)
        countDownTimer.text = minutes + ":" + seconds // Setting text for label (Works perfectly)

        let text = minutes + ":" + seconds
        countDownTimerButton.setTitle(text, for: .normal) // Setting text for button, (Text flashes everytime it is set)
        count -= 1
    }

}

Answer 1

这是通过设置按钮标题文本引起的。只需将按钮的类型设置为自定义，闪烁应停止

Answer 2

闪烁，因为每当你-1尝试这个时，它就会被击中

    @IBOutlet weak var countDownTimer: UILabel!
@IBOutlet weak var countDownTimerButton: UIButton!
var count = 120

override func viewDidLoad() {
    super.viewDidLoad()

    var _ = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(update), userInfo: nil, repeats: true)
    // Do any additional setup after loading the view.
}


func update() {

    if(count > 0){
        let minutes = String(count / 60)
        let seconds = String(count % 60)
        countDownTimer.text = minutes + ":" + seconds // Setting text for label (Works perfectly)

        let text = minutes + ":" + seconds

        count -= 1
    }
countDownTimerButton.setTitle(text, for: .normal) // Setting text for button, (Text flashes everytime it is set)

}

使用计时器功能Swift设置标题时，按钮文本会闪烁

2 个答案: