How to print a different Sales Invoice per company in AX

If you want to print a different Sales Invoice per every company you have, you must change the method printJournal in the table CustInvoiceJour and the form CustInvoiceJournal (MenuButton "SalesInvoiceShow" -> Copy, Original and Original print):

Modified method printJournal for the table CustInvoiceJour:

server void  printJournal(SalesFormLetter      salesFormLetter = null,
                          RecordSortedList     journalList     = null,
                          NoYes                copy            = NoYes::No)
{
    Args                parameters = new Args();
    MenuFunction        salesInvoiceMenu;
    ;

    // Show the correct report for the every company
    switch (strupr(curExt()))
    {
        case "OPP":
            salesInvoiceMenu = new MenuFunction(menuitemoutputstr(OPPSalesInvoice),MenuItemType::Output);
            break;
        
        default:
            salesInvoiceMenu = new MenuFunction(menuitemoutputstr(SalesInvoice),MenuItemType::Output);
    }
    // End

    parameters.caller(salesFormLetter);

    if (journalList)
        parameters.object(journalList);
    else
        parameters.record(this);

    salesInvoiceMenu.run(parameters);
}

For every MenuItemButton below the SalesInvoiceShow, you must override the clicked method as follows:

void clicked()
{
    Args                parameters = new Args();
    MenuFunction        salesInvoiceMenu;
    ;

    // Let the menuItemButton as this, with original parameters but
    // don't call super, to avoid call directly the report SalesInvoice
    //super();

    switch (strupr(curExt()))
    {
        case "OPP":
            salesInvoiceMenu = new MenuFunction(menuitemoutputstr(OPPSalesInvoiceCopy),MenuItemType::Output);
            break;

        default:
            salesInvoiceMenu = new MenuFunction(menuitemoutputstr(SalesInvoiceCopy),MenuItemType::Output);
    }

    parameters.caller(this);
    parameters.record(CustInvoiceJour);

    salesInvoiceMenu.run(parameters);
    // End
}

NOTE: You must use SalesInvoiceCopy, SalesInvoiceOriginal and SalesInvoice por Copy, Original and Original print respectively.