Question

我正在尝试向视图添加平移手势，但我不知道为什么它不起作用。这是我的UIView的代码：

    self.infoView = UIView()
    self.mapView.addSubview(infoView)
    infoView.backgroundColor = .white
    infoView.layer.cornerRadius = 10.0
    infoView.layer.masksToBounds = true
    infoView.isUserInteractionEnabled = true
    infoView.translatesAutoresizingMaskIntoConstraints = false

    let panGesture = UIPanGestureRecognizer(target: self, action: #selector(self.moveInfoView(recognizer:)))
    infoView.addGestureRecognizer(panGesture)

我在UIViewController中将其定义为：

var infoView: UIView!

我的平移手势方法如下：

@objc func moveInfoView(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.zero, in: self.view)
}

我真的看不到我的错误。似乎那里的一切都正确，但似乎我错了。你能指出我的错误吗？

更新

我的限制：

let constraints = [
        // InfoView constraints
        NSLayoutConstraint(item: infoView, attribute: .bottom, relatedBy: .equal, toItem: self.view.safeAreaLayoutGuide, attribute: .bottom, multiplier: 1.0, constant: 0.0),
        NSLayoutConstraint(item: infoView, attribute: .leading, relatedBy: .equal, toItem: self.view, attribute: .leading, multiplier: 1.0, constant: 0.0),
        NSLayoutConstraint(item: infoView, attribute: .trailing, relatedBy: .equal, toItem: self.view, attribute: .trailing, multiplier: 1.0, constant: 0.0),
        infoViewHeightConstraint]

其中

let infoViewHeightConstraint = infoView.heightAnchor.constraint(greaterThanOrEqualToConstant: 112.0)

Answer 1

我怀疑问题在于您的视图是x = [1,2,3] x[0] = 10 y = (1,2,3) y[0] = 10 # this will raise an error. tuple is not mutable. y = x id(y) == id(x) #gives true. since y is a reference to x y[0] = 10 print(y) [10, 2, 3] print(x) [10, 2, 3] # x is changed as well! y and x are same same.的子视图。地图视图已经添加了许多手势识别器，并且手势识别器回调已发送到GMSMapView实例，而不是您的子视图。尽管GMSMapView上有一个settings属性，可让您配置地图的用户界面设置。尝试以下代码以启用手势：

GMSMapView

还有其他可以在此处自定义的设置。希望这会有所帮助

Swift中UIPanGestureRecognizer的奇怪问题

1 个答案: