Ios 向标签添加手势？

Swift 4 iOS 11

尝试使用此代码向标签添加手势时，它会触发，但会使用无法识别的选择器崩溃

尝试使用@objc和不使用@objc，也尝试使用@selector（ViewController.copyURL），尝试打开isUserInteractiveEnabled=true；无效

@IBOutlet weak var zeroURL: UILabel!

let press = UILongPressGestureRecognizer(target: zeroURL, action: #selector(copyURL))
view.addGestureRecognizer(press)

@objc func copyURL() {
    UIPasteboard.general.string = self.zeroURL.text
    print("copied")
    zeroURL.alpha = 0
    UIView.animate(withDuration: 0.75, delay: 0.25, options: [.curveEaseOut], animations: {
        self.zeroURL.alpha = 1.0
    }) { (status) in
        // do nothing
    }
}

替换这个

let press = UILongPressGestureRecognizer(target: zeroURL, action: #selector(copyURL))
view.addGestureRecognizer(press)

与

因为目标应该包含选择器方法的实现

替换此

let press = UILongPressGestureRecognizer(target: zeroURL, action: #selector(copyURL))
view.addGestureRecognizer(press)

与

---

由于目标应该包含选择器方法的实现

目标应该是self，因此需要将手势识别器添加到标签，而不是视图

let press = UILongPressGestureRecognizer(target: self, action: #selector(copyURL))
zeroURL.addGestureRecognizer(press)

---

在这里的第一行，您正在配置手势识别器，告诉它识别手势时要使用的目标操作是

self.copyURL

。第二行将手势添加到

UILabel

目标应该是self，您需要将手势识别器添加到标签，而不是视图

let press = UILongPressGestureRecognizer(target: self, action: #selector(copyURL))
zeroURL.addGestureRecognizer(press)

---

在这里的第一行，您正在配置手势识别器，告诉它识别手势时要使用的目标操作是

self.copyURL

。第二行将手势添加到

UILabel

使目标

self

而不是

zeroURL

，如下所示：

let press = UILongPressGestureRecognizer(target: self, action:#selector(copyURL))
zeroURL.addGestureRecognizer(press)

@objc func copyURL() {
    UIPasteboard.general.string = self.zeroURL.text
    print("copied")
    zeroURL.alpha = 0
    UIView.animate(withDuration: 0.75, delay: 0.25, options: [.curveEaseOut], animations: {
    self.zeroURL.alpha = 1.0
    }) { (status) in
        // do nothing
    }
}

zeroURL.addGestureRecognizer(press)

编辑：仅在

ui标签上添加长按手势

，而不是在

视图上添加长按手势

，如下所示：

let press = UILongPressGestureRecognizer(target: self, action:#selector(copyURL))
zeroURL.addGestureRecognizer(press)

@objc func copyURL() {
    UIPasteboard.general.string = self.zeroURL.text
    print("copied")
    zeroURL.alpha = 0
    UIView.animate(withDuration: 0.75, delay: 0.25, options: [.curveEaseOut], animations: {
    self.zeroURL.alpha = 1.0
    }) { (status) in
        // do nothing
    }
}

zeroURL.addGestureRecognizer(press)

---

使目标

self

而不是

zeroURL

如下所示：

let press = UILongPressGestureRecognizer(target: self, action:#selector(copyURL))
zeroURL.addGestureRecognizer(press)

@objc func copyURL() {
    UIPasteboard.general.string = self.zeroURL.text
    print("copied")
    zeroURL.alpha = 0
    UIView.animate(withDuration: 0.75, delay: 0.25, options: [.curveEaseOut], animations: {
    self.zeroURL.alpha = 1.0
    }) { (status) in
        // do nothing
    }
}

zeroURL.addGestureRecognizer(press)

编辑：仅在

ui标签上添加长按手势

，而不是在

视图上添加长按手势

，如下所示：

let press = UILongPressGestureRecognizer(target: self, action:#selector(copyURL))
zeroURL.addGestureRecognizer(press)

@objc func copyURL() {
    UIPasteboard.general.string = self.zeroURL.text
    print("copied")
    zeroURL.alpha = 0
    UIView.animate(withDuration: 0.75, delay: 0.25, options: [.curveEaseOut], animations: {
    self.zeroURL.alpha = 1.0
    }) { (status) in
        // do nothing
    }
}

zeroURL.addGestureRecognizer(press)

---

什么是您的

zeroURL

？什么是您的

zeroURL

？是的，这就解决了它。。。但我现在到处都有记者。我只想在zeroURL上长按一下。是的，这就解决了它。。。但我现在到处都有记者。我只想长按zeroURL。