Form Personalized when click chekbox
i want to create personalized when auto create PO (responsibility: Purchasing, menu: autocreate, version: r12).
even trigger is when user clik chekbox (when validate record) to add requisition so it can be processes into PO
i have tried to set personalized with conditiion to get :REQ_LINES.REQUISITION_HEADER_ID but it seem not working when user click chekbox that not in active line (example: cursor in line 1 then i click chekbox in line3 --> oracle update the checkbox in line3 firstly and after that move into line3, so when it case happen i get :REQ_LINES.REQUISITION_HEADER_ID in line1)