长按通过按钮识别手势-Swift 3

Question

我是Swift的新手，我正在尝试制作定时器（在标签中），该定时器从长按按钮开始。 同时，我想在按下长按按钮时更改长按按钮的图像。 我离开按钮，我希望按钮恢复原状。

可能是什么问题？

@IBOutlet weak var myBtn: UIButton!

func initGesture()
{

    {   let longGesture = UILongPressGestureRecognizer(target: self, action: #selector(longTap(_:)))
        myBtn.addGestureRecognizer(longGesture)
    }
}

func TimerAction()
{
    Timer.scheduledTimer(timeInterval: 5, target: self, selector: #selector(longTap), userInfo: nil, repeats: false)
    myBtn.setImage(UIImage(named: "xxx.png"), for: .normal)


}
@IBOutlet weak var lbl: UILabel!

func start()
{
    timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: (#selector(ViewController2.updateTime as (ViewController2) -> () -> ())), userInfo: nil, repeats: true)

}

func updateTimer () {
    count += 1
    let hours = Int(count) / 3600
    let minutes = Int(count) / 60 % 60
    let seconds = Int(count) % 60
    label.text = String(format: "%02i:%02i:%02i",hours,minutes,seconds)
}

func reset()
{
    timer.invalidate()
    count = 0
    label.text = "00:00:00"

}

Answer 1

您可以获得TouchUpInside和TouchUpOutside以及按钮的TouchDown操作不使用手势。

class ViewController: UIViewController {
@IBOutlet weak var lbl: UILabel!
@IBOutlet weak var myBtn: UIButton!
var timer: NSTimer!

override func viewDidLoad() {
      super.viewDidLoad()
      myBtn.addTarget(self, action: "buttonDown:", forControlEvents: .TouchDown)
      myBtn.addTarget(self, action: "buttonUp:", forControlEvents: [.TouchUpInside, .TouchUpOutside])
    }
func buttonDown(sender: AnyObject) {
    singleFire()
    timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "rapidFire", userInfo: nil, repeats: true)
}

func buttonUp(sender: AnyObject) {
    timer.invalidate()
    count = 0
    label.text = "00:00:00"
}

func singleFire() {
    myBtn.setImage(UIImage(named: "xxx.png"), for: .normal)
}

func rapidFire() {
    count += 1
    let hours = Int(count) / 3600
    let minutes = Int(count) / 60 % 60
    let seconds = Int(count) % 60
    label.text = String(format: "%02i:%02i:%02i",hours,minutes,seconds)
}

}

Answer 2

您应该实现按钮事件，而不是在此处使用手势识别器。 我谈论的按钮事件是TouchDown和TouchUpInside。 TouchDown会告诉您何时按下按钮，touchupinside会告诉您何时用户将手指从按钮上抬起。

因此，您将更改按钮图像并在触地事件上启动计时器。 然后，您将在touchupinside事件上恢复原状。

https://developer.apple.com/documentation/uikit/uicontrolevents

Answer 3

尝试这个，

首先根据其状态设置按钮的图像。

    self.arrowIcon.setImage(UIImage(named: "normalImage.png"), for: .normal)
    self.arrowIcon.setImage(UIImage(named: "pressedImage.png"), for: .highlighted)