Activity 当搜索视图控制器俯卧撑时，指示器不会出现在自定义 UIAlertView 的中心 VC

Question

我想在包含 table 视图的 UIAlertViewController 上显示 activity 指示器，所以它工作得很好，但是第二种情况是搜索控制器出现在然后 UIAlertViewController activity 指示器不会出现在 UIAlertViewController 的中心。

在父级上附加 searchVC 之前附加图像

当 searchVC 添加到 Parent 时

以下是activity指标的代码

var actInd: UIActivityIndicatorView = UIActivityIndicatorView()

func startActivityIndicator() {
    self.view.isUserInteractionEnabled = false
    let loadingView: UIView = UIView()
    loadingView.frame =  CGRect(x: 0, y: 0, width: 80.0, height: 80.0)
    loadingView.center = self.view.center
    loadingView.backgroundColor = UIColor(red: 44/255, green: 44/255, blue: 44/255, alpha: 0.7)
    loadingView.clipsToBounds = true
    loadingView.layer.cornerRadius = 10
    actInd.frame = CGRect(x: 0, y: 0, width: 40.0, height: 40.0)
    actInd.style = .whiteLarge
    actInd.center = CGPoint(x: loadingView.frame.size.width / 2, y: loadingView.frame.size.height / 2)
    loadingView.addSubview(actInd)
    self.view.addSubview(loadingView)
    actInd.startAnimating()
}
func stopActivityIndicator() {
    self.view.isUserInteractionEnabled = true
    actInd.stopAnimating()
    let view = actInd.superview
    view?.removeFromSuperview()
}

以上代码是我在 UIViewController

的扩展中添加的

Answer 1

终于通过如下方式设置约束解决了

func startActivityIndicator() {
    self.view.isUserInteractionEnabled = false
    let loadingView: UIView = UIView()
    loadingView.translatesAutoresizingMaskIntoConstraints = false
    actInd.translatesAutoresizingMaskIntoConstraints = false
    self.view.addSubview(loadingView)
    loadingView.addSubview(actInd)
    loadingView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
    loadingView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
    loadingView.widthAnchor.constraint(equalToConstant: 80.0).isActive = true
    loadingView.heightAnchor.constraint(equalToConstant: 80.0).isActive = true
    loadingView.center = self.view.center
    loadingView.backgroundColor = UIColor(red: 44/255, green: 44/255, blue: 44/255, alpha: 0.7)
    loadingView.clipsToBounds = true
    loadingView.layer.cornerRadius = 10
    actInd.leadingAnchor.constraint(equalTo: loadingView.leadingAnchor).isActive = true
    actInd.trailingAnchor.constraint(equalTo: loadingView.trailingAnchor).isActive = true
    actInd.topAnchor.constraint(equalTo: loadingView.topAnchor).isActive = true
    actInd.bottomAnchor.constraint(equalTo: loadingView.bottomAnchor).isActive = true
    actInd.style = .whiteLarge
    actInd.center = CGPoint(x: loadingView.frame.size.width / 2, y: loadingView.frame.size.height / 2)
    actInd.startAnimating()
}

Activity 当搜索视图控制器俯卧撑时，指示器不会出现在自定义 UIAlertView 的中心 VC

Activity Indicator not appears center on custom UIAlertView when search view controller push ups VC

ios

swift4

uialertview

uisearchcontroller

uiactivityindicatorview