滑块（UISlider）

        let slider = UISlider(frame: CGRect(x: 50, y: 100, width: 300, height: 30))
        
        slider.center = self.view.center
        //最小值
        slider.minimumValue = 0
        //最大值
        slider.maximumValue = 10
        //当前值
        //slider.value = 5.0
        slider.setValue(8.0, animated: true)
        
        //滑动方法
        //滑动停止后才触发方法
        slider.isContinuous = false
        slider.addTarget(self, action: #selector(slederClick(_:)), for: .valueChanged)
        
        //滑块两侧添加图标
        slider.minimumValueImage = UIImage(named: "jian")
        slider.maximumValueImage = UIImage(named: "jia")
        
        
        
        self.view.addSubview(slider)

    func slederClick(_ slider:(UISlider))
    {
        print("\(slider.value)")
    }