ios - 点击 UISlider 以设置值

Question

我创建了一个 slider (用作视频控件，就像底部的 YouTube)并设置最大值(持续时间)和最小值。然后使用 SeekToTime 更改当前时间。现在，用户可以滑动 slider 的拇指来改变值

我想要实现的是让用户点击 slider 上的任意位置并设置视频的当前时间。

我从 this answer 得到了一个方法, 我尝试将它应用到我的案例中，但无法使其工作

class ViewController: UIViewController, PlayerDelegate {

var slider: UISlider!

override func viewDidLoad() {
  super.viewDidLoad()

  // Setup the slider
}

func sliderTapped(gestureRecognizer: UIGestureRecognizer) {
  //  print("A")

  let pointTapped: CGPoint = gestureRecognizer.locationInView(self.view)

  let positionOfSlider: CGPoint = slider.frame.origin
  let widthOfSlider: CGFloat = slider.frame.size.width
  let newValue = ((pointTapped.x - positionOfSlider.x) * CGFloat(slider.maximumValue) / widthOfSlider)

  slider.setValue(Float(newValue), animated: true)      
 }
}

我认为这应该可行，但运气不好。然后我尝试通过尝试将“A”打印到日志进行调试，但显然它没有进入 sliderTapped() 函数。

我做错了什么？或者是否有更好的方法来实现我想要实现的目标？

Answer 1

看起来您需要根据上面的代码示例在 viewDidLoad() 中实际初始化点击手势识别器。那里有一条评论，但我没有看到任何地方正在创建识别器。

swift 2:

class ViewController: UIViewController {

    var slider: UISlider!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Setup the slider

        // Add a gesture recognizer to the slider
        let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: "sliderTapped:")
        self.slider.addGestureRecognizer(tapGestureRecognizer)
    }

    func sliderTapped(gestureRecognizer: UIGestureRecognizer) {
        //  print("A")

        let pointTapped: CGPoint = gestureRecognizer.locationInView(self.view)

        let positionOfSlider: CGPoint = slider.frame.origin
        let widthOfSlider: CGFloat = slider.frame.size.width
        let newValue = ((pointTapped.x - positionOfSlider.x) * CGFloat(slider.maximumValue) / widthOfSlider)

        slider.setValue(Float(newValue), animated: true)      
    }
}

swift 3:

class ViewController: UIViewController {

    var slider: UISlider!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Setup the slider

        // Add a gesture recognizer to the slider
        let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(sliderTapped(gestureRecognizer:)))
        self.slider.addGestureRecognizer(tapGestureRecognizer)
    }

    func sliderTapped(gestureRecognizer: UIGestureRecognizer) {
        //  print("A")

        let pointTapped: CGPoint = gestureRecognizer.location(in: self.view)

        let positionOfSlider: CGPoint = slider.frame.origin
        let widthOfSlider: CGFloat = slider.frame.size.width
        let newValue = ((pointTapped.x - positionOfSlider.x) * CGFloat(slider.maximumValue) / widthOfSlider)

        slider.setValue(Float(newValue), animated: true)
    }
}