Error while running report from menuitem

Hi all,

I am facing this issue, I am doing select record from grid and pass to RDP class. I have controller class in controller class preRunModilfy method I get the hidden parameter and pass to DP class,kindly check the code below if any thing is wrong then please tell me how to write correct it.Thanks

CustInvoiceContract object not initialized.

Stack trace

(C)\Classes\CustInvoiceController\preRunModifyContract - line 12
(C)\Classes\SrsReportRunController\runReport - line 38
(C)\Classes\SrsReportRunController\run - line 29
(C)\Classes\SysOperationController\startOperation - line 10
(C)\Classes\SrsReportRunController\startOperation - line 12
(C)\Classes\CustInvoiceController\main - line 8
(C)\Classes\FormFunctionButtonControl\Clicked

class CustInvoiceController extends SrsReportRunController
{
}

protected void preRunModifyContract()
{
CustInvoiceJour custInvoicejour;

CustInvoiceContract contract ;

contract = this.parmReportContract().parmRdpContract() as CustInvoiceContract;

custInvoicejour = this.parmArgs().record();

contract.parminvoiceId(custInvoicejour.InvoiceId);
super();
}

public static client void main(Args args)
{
CustInvoiceController ssrsDemoController;
ssrsDemoController = new CustInvoiceController();
ssrsDemoController.parmArgs(args);
ssrsDemoController.parmReportName(ssrsReportStr(CustomerInvoiceReport,CustomerInvoiceDesign));
ssrsDemoController.parmShowDialog(false);
ssrsDemoController.startOperation();
}

[DataContractAttribute]
class CustInvoiceContract
{
InvoiceId invoiceId;
}

[DataMemberAttribute('InvoiceId')]
public InvoiceId parminvoiceId(InvoiceId _invoiceId = invoiceId)
{
invoiceId = _invoiceId;
return invoiceId;
}