在swift中更改多种颜色的UISlider轨道颜色？

Question

我可以使用我获得的值（sender.value）来改变滑块移动时的颜色吗？当滑块移动时，我试图将颜色从绿色更改为黄色到红色。请快速帮助谢谢！

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

请尝试以下代码：

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

Answer 2

试试这个：

import Foundation
import UIKit

class AnnotationPhotoWidget: UIViewController  {
    let brokeSlider = UISlider(frame:CGRectMake(5, 440, 355, 20))

    override func viewDidLoad() {
        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) {
        if sender.value <= 0.3 {
            brokeSlider.minimumTrackTintColor = UIColor.greenColor()
        } else if sender.value > 0.3 && sender.value <= 0.6 {
            brokeSlider.minimumTrackTintColor = UIColor.yellowColor()
        } else {
            brokeSlider.minimumTrackTintColor = UIColor.redColor()
        }
    }
}