在父視圖中重寫 func point(inside point: CGPoint, with event: UIEvent?) -> Bool

override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
        if self.bounds.contains(point) {
            return true
        }
        for subView:UIView in self.subviews {
            let hitPoint = self.convert(point, to: subView)
            if subView.bounds.contains(hitPoint) {
                return true
            }
        }
        return false
    }