protocol LoadingNewDataDelegate: class {
    func updateProgress(progress : Float)
}

class LoadingDataHelper: NSObject {
        var delegate: LoadingNewDataDelegate?

    func updateProgressInViewController() {
        delegate?.updateProgress(0.3)
    }

}

class LoadingDataViewController: UIViewController, LoadingNewDataDelegate {

let loadingDataHelper: LoadingDataHelper = LoadingDataHelper()

    override func viewDidLoad() {
        super.viewDidLoad()
        loadingDataHelper.delegate = self
    }

    func updateProgress(progress : Float) {
        self.progressBar.setProgress(progress, animated: true)
        self.progressBar.setNeedsDisplay()
    }
}