protected override void OnNavigatedFrom(Windows.UI.Xaml.Navigation.NavigationEventArgs e)
        {
            base.OnNavigatedFrom(e);

            if (printReport != null)
            {
                printReport.UnregisterForPrinting();
                printReport = null;
            }
        }
        async private void buttonPrint_Click(object sender, RoutedEventArgs e)
        {
            #region Get Report

            string fileName = null;
            switch (listBoxReports.SelectedIndex)
            {
            case 0:
                fileName = "StimulsoftResources\\Reports\\SimpleList.mrt";
                break;

            case 1:
                fileName = "StimulsoftResources\\Reports\\MultiColumnList.mrt";
                break;

            case 2:
                fileName = "StimulsoftResources\\Reports\\MasterDetail.mrt";
                break;

            case 3:
                fileName = "StimulsoftResources\\Reports\\TwoMastersOnOneDetail.mrt";
                break;
            }

            #endregion

            if (fileName == null)
            {
                return;
            }

            #region Load Report

            var storage = await Windows.ApplicationModel.Package.Current.InstalledLocation.GetFileAsync(fileName);

            var report = new StiReport();
            await report.LoadAsync(storage);

            report.RegBusinessObject("Data", "Data", new Data());
            await report.RenderAsync();

            #endregion

            #region Print report

            if (printReport != null)
            {
                printReport.UnregisterForPrinting();
                printReport = null;
            }

            if (printReport == null)
            {
                printReport = new StiPrintReport(report);
                printReport.RegisterForPrinting();
            }

            await printReport.PrintAsync();

            #endregion
        }