ios - 快速更改多种颜色的 UISlider 轨道颜色？

Question

我可以使用我获得的值 (sender.value) 来改变 slider 移动时的颜色吗？随着 slider 的移动，我正在尝试将颜色从绿色更改为黄色再更改为红色。请 swift 帮忙谢谢!

let brokeSlider = UISlider(frame:CGRectMake(5, 440, 355, 20))
            brokeSlider.minimumValue = 0
            brokeSlider.maximumValue = 1
            brokeSlider.continuous = true
            brokeSlider.tintColor = UIColor.blackColor()
            brokeSlider.value = 0
            brokeSlider.addTarget(self, action: #selector(AnnotationPhotoWidget.sliderValueDidChange(_:)), forControlEvents: .ValueChanged)
            self.view.addSubview(brokeSlider)

    func sliderValueDidChange(sender:UISlider) {
            print("value--\(sender.value)")
    }

Answer 1

试试下面的代码:

func sliderValueDidChange(sender:UISlider) {
     print("value--\(sender.value)")
     if sender.value <= 0.3 {
        brokeSlider.minimumTrackTintColor = UIColor.green
     } else if sender.value > 0.3 && sender.value <= 0.6 {
           brokeSlider.minimumTrackTintColor = UIColor.yellow
     } else {
          brokeSlider.minimumTrackTintColor = UIColor.red
     }
}