Question

我有一个UIButton突出显示状态涉及删除阴影。我尝试做的是在按钮上加UILongPressGestureRecognizer：

let gesture = UILongPressGestureRecognizer(target: self, action: #selector(self.removeShadow))
gesture.numberOfTapsRequired = 1
gesture.numberOfTouchesRequired = 1
gesture.delaysTouchesBegan = false
gesture.delaysTouchesEnded = false
gesture.minimumPressDuration = 0.01
self.addGestureRecognizer(gesture)

然后在我的行动中，我使用状态隐藏并显示阴影：

 @objc func removeShadow(gesture: UILongPressGestureRecognizer) {
    if gesture.state == .recognized {
        UIView.animate(withDuration: 0.1, animations: {
            self.layer.shadowOpacity = 0
        })
    } else if gesture.state == .ended {
        UIView.animate(withDuration: 0.1, animations: {
            self.layer.shadowOpacity = 0.15
        })
    }
}

然而，这似乎并没有触发任何事情。影子一直生活在按钮下。我在这里错过了什么吗？

感谢。

Answer 1

按钮的选择器正在覆盖您的手势识别器。在您的场景中，覆盖按钮并在选中时隐藏其阴影会更好。

class ShadowButton: UIButton {
    override var isHighlighted: Bool {
        didSet {
            UIView.animate(withDuration: 0.1) {
                self.layer.shadowOpacity = self.isHighlighted ? 0 : 0.15
            }
        }
    }
}

在UIButton被保持时移除阴影

1 个答案: