在左下角视图上以编程方式进行垂直UISlider约束(Swift 4.2)

let slider = UISlider()
slider.minimumValue = 0
slider.maximumValue = 100
slider.value = 50
slider.translatesAutoresizingMaskIntoConstraints = false

view.addSubview(slider)

let constraints = [
    slider.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20),
    slider.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -20),
    slider.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20)
]
NSLayoutConstraint.activate(constraints)