// Initialize the progress view
let loadingView:ZXLoadingView = ZXLoadingView.init(frame:CGRect.init(x: self.view.center.x, y: self.view.center.y, width: 100, height: 100))

// Set the line width of the loadingView
loadingView.lineWidth = 2.0
// Set the tint color of the loadingView
loadingView.tintColor = .red

// Add it as a subview
self.view.addSubview(loadingView)

...

// Start & stop animations
loadingView.startAnimating()
loadingView.stopAnimating()