ios - 如何让 UIView 在按下时改变颜色？

Question

我想让 UIView 在按下后突出显示，并在释放后返回正常颜色。这样做的最佳做法是什么？

Answer 1

UIView 的子类:

class CustomView: UIView {
    override init(frame: CGRect) {
        super.init(frame: frame)
        backgroundColor = UIColor.blue
    }

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

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        super.touchesBegan(touches, with: event)
        backgroundColor = UIColor.red
    }

    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
        super.touchesEnded(touches, with: event)
        backgroundColor = UIColor.blue
    }
}

Apple 关于覆盖 touchesBegan 和 touchesEnded:

When creating your own subclasses, call super to forward any events that you do not handle yourself. If you override this method without calling super (a common use pattern), you must also override the other methods for handling touch events [i.e. touchesEnded, touchesMoved, touchesCancelled], even if your implementations do nothing.

进一步阅读:

https://developer.apple.com/documentation/uikit/uiview

Proper practice for subclassing UIView?