Form Personalization to view documents only for Approved Purchase Orders

Hi,

Can we personalize the Purchase order summary form such that

Inquire > View Document will be allowed for only Approved purchase orders.

Purchasing User > Purchase Order Summary >Find an Incomplete PO >

In the menu bar click 'Inquire >   View Document'

I could open the PO pdf

To prevent this we wish to personalize

the Purchase order summary form such that

Inquire > View Document will be allowed for only Approved purchase orders.

If anyone has done this, please give the steps.

Thx,