Swift如何将触摸按钮限制在手机的左侧和右侧

Question

以下是我的应用程序的一部分，当您单击屏幕时，它将注册触摸并根据触摸移动到上一张照片或下一张照片。现在，只要您触摸屏幕，它就会注册并移动到上一个或下一个图像。我想限制它，只注册红色方块上的触摸，这样如果你触摸2个红色方块之间的任何东西，就不会发生任何事情。这是我的代码

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {


    for touch in touches {
        let location = touch.location(in: self.view)

       if location.x <  self.view.layer.frame.size.width / 2        {
  // touched left side of screen show previous image if exist

        }
        else {

     // touched right side of screen show next 

        }
    }
}

我认为关键是let location = touch.location（in：self.view）然后location.x知道你触摸的宽度位置。我想只注册点击最低10％的屏幕和最亮的10％的屏幕。任何建议都会很棒我正在使用swift 4。

（红色方块仅用于说明。我添加了使用照片编辑功能，它不是应用程序的一部分）

Answer 1

在ViewDidLoad中，你可以添加两个不可见的UIView以获得两侧的轻击手势，如下所示，

override func viewDidLoad() {
    super.viewDidLoad()

    let touchArea = CGSize(width: 80, height: self.view.frame.height)

    let leftView = UIView(frame: CGRect(origin: .zero, size: touchArea))
    let rightView = UIView(frame: CGRect(origin: CGPoint(x: self.view.frame.width - touchArea.width, y: 0), size: touchArea))

    leftView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(leftViewTapped)))
    rightView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(rightViewTapped)))

    leftView.backgroundColor = .clear
    rightView.backgroundColor = .clear

    self.view.addSubview(leftView)
    self.view.addSubview(rightView)
}

@objc func leftViewTapped() {
    print("Left")
}

@objc func rightViewTapped() {
    print("Right")
}

---

要么

您可以按如下所示更新当前有问题的方法，以获得所需的结果。

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    guard let location = touches.first?.location(in: self.view) else { return }

    let touchAreaWidth: CGFloat = 80

    if location.x <= touchAreaWidth {
        print("Left area touched")
    } else if location.x >= (self.view.frame.size.width - touchAreaWidth) {
        print("Right area touched")
    } else {
        print("Ignore in-between touch.")
    }
}