ios - 在iOS中触摸时如何模糊自定义按钮的标题，如系统UIButton的标题？

Question

我有以下自定义按钮：

class GreenButton: UIButton {

override init(frame: CGRect) {
    super.init(frame: frame)
    setup()
}

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    setup()
}

private func setup() {
    backgroundColor = .green
    layer.cornerRadius = 4
    setTitleColor(.white, for: .normal)
    titleLabel?.font = .systemFont(ofSize: 22, weight: .bold)
}
}

但我希望它的标题在触摸时模糊，就像系统 UIButton 的行为一样。如果我这样声明我的按钮GreenButton(type: .system)，它的标题会模糊，但字体不会改变。如果我将它声明为GreenButton()，它的字体是可以的，但它的标题并不模糊。如何解决问题？

Answer 1

为突出显示的状态设置不同的颜色：

private func setup() {
    backgroundColor = .green
    layer.cornerRadius = 4
    // set title normal color
    setTitleColor(.white, for: .normal)
    // set title highlighted color
    setTitleColor(.gray, for: .highlighted)
    titleLabel?.font = .systemFont(ofSize: 22, weight: .bold)
}

Answer 2

您还可以通过以下方式实现此目的：

class GreenButton: UIButton {

    override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setup()
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        setTitleColor(UIColor(white:1.0 , alpha: 0.5), for: .normal)
    }
    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
        setTitleColor(.white, for: .normal)
    }

    private func setup() {
        backgroundColor = .green
        layer.cornerRadius = 4
        setTitleColor(.white, for: .normal)
        titleLabel?.font = .systemFont(ofSize: 22, weight: .bold)
    }
}