iOS How do I remove glow/shadow from UISlider

Question

How do I remove the glow/shadow from this UISlider?

Answer 1

It turns out, all I needed to do was set a custom thumb image and the shadow doesn't exist.

Answer 2

I do this in the didSet of the UISlider (Swift 3):

@IBOutlet weak var slider: UISlider!{
    didSet{
        slider.setThumbImage(<image when not touched>, for: .normal)
        slider.setThumbImage(<image when touched>, for: .highlighted)
    }
}