There is a solution for customizing Standard Po Print Template in Oracle Apps R12
Customizing PO Print standard Template in Oracle Apps R12 (12.0.6) including
Assuming that one should have good knowledge on XML publisher.
Navigate to XML Publisher Administrator Responsibility
1. Query the Standard Purchase Order Style sheet and download the POXML data file.
2. Design the template (RTF) based on POXML data file with all mapping (fields).
3. Export the RTF template to XSL-FO style sheet.
4. Replace the document type and style sheet in Purchasing Responsibility - > Setup - > Purchasing - > Document Types
5. Localization - > for adding localization information one need to create a custom view including the entire field from po_headers_xml and po_lines_xml.
Include the above views in PO_COMMUNICATION_PVT package which is being called by Po Communication Java Program.
6. Customize the PO Approval workflow and update the above package and change the workflow in purchasing setup.
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