class MyView : UIView {

  func buildMyView() {
    var indicatorView :UIActivityIndicatorView!
    let indicatorSize : CGFloat = 120
    loadingIndicator = UIView(frame: CGRect(origin: CGPoint.zero, size: CGSize(width: indicatorSize, height: indicatorSize)))
    loadingIndicator.backgroundColor = UIColor.darkGray.withAlphaComponent(0.7)
    loadingIndicator.layer.cornerRadius = 10.0
    indicatorView = UIActivityIndicatorView(activityIndicatorStyle: .white)
    indicatorView.hidesWhenStopped = false

    let inset :CGFloat = 20.0
    let insets = UIEdgeInsets(top: inset, left: inset, bottom: inset, right: inset)
    loadingIndicator.fit(subView: indicatorView, .horizontallyAndVertically, with: insets)
    view.center(subView: loadingIndicator, orientated: .horizontallyAndVertically, withOffsets: CGPoint(x: 0, y: -100))
  }

}