ssrs report dont show print preview

I have the following code which prints out the sales packing slip however its printing to both screen and to the file. Just wondering is there any way to prevent showing the report on screen

static void SR_SaveReportToPDFFromController(Args _args)
{
SalesPackingSlipController SalesPackingSlipController;
SalesPackingSlipContract SalesPackingSlipContract;
salesTable salesTable;
Args args = new Args();
SrsReportRunImpl srsReportRun;
CustPackingSlipJour CustPackingSlipJour;
ReportName reportName = “SalesPackingSlip.Report”;
str invoiceFileName;

;

select firstOnly CustPackingSlipJour
where CustPackingSlipJour.SalesId == ‘SO011043’;

salesTable = SalesTable::find(CustPackingSlipJour.SalesId);
args.record(CustPackingSlipJour);
SalesPackingSlipController = new SalesPackingSlipController();
SalesPackingSlipController.parmReportName(reportName);
infolog.setInfoLogLevel(SysInfoLogLevel::None);
SalesPackingSlipContract = SalesPackingSlipController.parmReportContract().parmRdpContract();
SalesPackingSlipContract.parmRecordId(CustPackingSlipJour.RecId); // Record id must be passed otherwise the report will be empty
SalesPackingSlipController.parmArgs(args);
srsReportRun = SalesPackingSlipController.parmReportRun() as SrsReportRunImpl;
SalesPackingSlipController.run();
SalesPackingSlipController.parmReportRun(srsReportRun);
SalesPackingSlipController.parmReportContract().parmPrintSettings().printMediumType(SRSPrintMediumType::File);
SalesPackingSlipController.parmReportContract().parmPrintSettings().overwriteFile(true);
SalesPackingSlipController.parmReportContract().parmPrintSettings().fileFormat(SRSReportFileFormat::PDF);
invoiceFileName = “AX_” + CustPackingSlipJour.SalesId + “.pdf”;
SalesPackingSlipController.parmReportContract().parmPrintSettings().fileName(‘c:\lori\’ + invoiceFileName);
SalesPackingSlipController.runReport();
infolog.setInfoLogLevel(SysInfoLogLevel::All);

}

any help would really be appreciated