A little view controller that shows a loading indicator. (great for using as a placeholder VC while your parent does a network request)

LoadingVC

class LoadingVC: UIViewController {

    lazy var loadingIndicator: UIActivityIndicatorView = {
        let loading = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.gray)
        return loading
    }()

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white
        loadingIndicator.frame = view.bounds
        view.addSubview(loadingIndicator)
    }
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        loadingIndicator.startAnimating()
    }
}