无法在动态添加的 UILabel 上添加手势

Question

我正在尝试在动态创建的标签上添加手势，但此代码不起作用，但它不起作用。我做错了什么？

let label = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 21))
label.center = CGPoint(x: 160, y: 285)
label.textAlignment = .center
label.text = field.text
label.isZoomEnabled = true;
label.minFontSize = 10;
label.maxFontSize = 80;
label.adjustsFontSizeToFitWidth = true;
label.setNeedsLayout()
label.isUserInteractionEnabled = true
let panRecognizer = UITapGestureRecognizer(target: self, action:Selector(("handlePan:")))
let rotateRecognizer = UITapGestureRecognizer(target: self, action:Selector(("handleRotate:")))
panRecognizer.delegate = self
rotateRecognizer.delegate = self
label.addGestureRecognizer(panRecognizer)
label.addGestureRecognizer(rotateRecognizer)
self.view.addSubview(label);
self.imagePicked.addSubview(label)

@IBAction func handlePan(recognizer:UIPanGestureRecognizer) {
    let translation = recognizer.translation(in: self.view)
    if let view = recognizer.view {
        view.center = CGPoint(x:view.center.x + translation.x,
                              y:view.center.y + translation.y)
    }
    recognizer.setTranslation(CGPoint(x:0,y:0), in: self.view)
}

@IBAction func handleRotate(recognizer : UIRotationGestureRecognizer) {
    if let view = recognizer.view {
        view.transform = view.transform.rotated(by: recognizer.rotation)
        recognizer.rotation = 0
    }
}

提前致谢。

Answer 1

是UIlabel'ssuperView的问题。

我假设 imagePicked 是 UIImageView 的一个实例，而 UIImageView's isUserInteractionEnabled 的默认值是 flase。

因此 imagePicked 及其所有子视图无法接收触摸事件。

要解决此问题，请启用 UIImageView 的 isUserInteractionEnabled 属性：

self.imagePicked.isUserInteractionEnabled = true;

Answer 2

您正在创建 UITapGestureRecognizer，但方法采用 UIPanGestureRecognizer 和 UIRotationGestureRecognizer。还更改了 selector 以便正确调用方法并将 IBActions 更改为方法。

用这个替换你的代码，它会工作正常，

let label = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 21))
    label.center = CGPoint(x: 160, y: 285)
    label.textAlignment = .center
    label.text = field.text
    label.isZoomEnabled = true;
    label.minFontSize = 10;
    label.maxFontSize = 80;
    label.adjustsFontSizeToFitWidth = true;
    label.setNeedsLayout()
    label.isUserInteractionEnabled = true
    let panRecognizer = UIPanGestureRecognizer(target: self, action:#selector(self.handlePan))
    let rotateRecognizer = UIRotationGestureRecognizer(target: self, action:#selector(self.handleRotate))
    panRecognizer.delegate = self
    rotateRecognizer.delegate = self
    label.addGestureRecognizer(panRecognizer)
    label.addGestureRecognizer(rotateRecognizer)
    self.view.addSubview(label);
    self.imagePicked.addSubview(label)

func handlePan(recognizer:UIPanGestureRecognizer) {
    let translation = recognizer.translation(in: self.view)
    if let view = recognizer.view {
        view.center = CGPoint(x:view.center.x + translation.x,
                              y:view.center.y + translation.y)
    }
    recognizer.setTranslation(CGPoint(x:0,y:0), in: self.view)
}

func handleRotate(recognizer : UIRotationGestureRecognizer) {
    if let view = recognizer.view {
        view.transform = view.transform.rotated(by: recognizer.rotation)
        recognizer.rotation = 0
    }
}

无法在动态添加的 UILabel 上添加手势

Unable To Add Gesture on Dynamically Added UILabel

uilabel

uigesturerecognizer

ios

swift3

xcode8