Button.isHighlighted 时如何更改边框颜色

我想知道如何让我的边界围绕我UIButton单击或突出显示时更改其内部文本的不透明度。

我的逻辑告诉我，它应该是这样的..但它似乎不起作用：

    //BTN STYLING

    btnstd.layer.cornerRadius = 5
    btnstd.layer.borderWidth = 1.5
    btnstd.layer.borderColor = UIColor.white.cgColor

    //Change bordercolor when highlighted
    if(btnstd.isHighlighted) {
    btnstd.layer.borderColor = UIColor(white:1,alpha:0.3).cgColor
    }

顺便说一句，这是放在我的ViewDidLoad()功能

您正在寻找的操作是.touchDown和任何东西.touchUp:

override func viewDidLoad() {
    super.viewDidLoad()
    theButton.setTitle("Normal", for: .normal)
    theButton.setTitle("Highlighted", for: .highlighted)
    theButton.layer.borderColor = UIColor.red.cgColor
    theButton.layer.borderWidth = 1
    theButton.addTarget(self, action: #selector(startHighlight), for: .touchDown)
    theButton.addTarget(self, action: #selector(stopHighlight), for: .touchUpInside)
    theButton.addTarget(self, action: #selector(stopHighlight), for: .touchUpOutside)
}
func startHighlight(sender: UIButton) {
    theButton.layer.borderColor = UIColor.green.cgColor
    theButton.layer.borderWidth = 1
}
func stopHighlight(sender: UIButton) {
    theButton.layer.borderColor = UIColor.red.cgColor
    theButton.layer.borderWidth = 1
}