Got it!  Now, all I need to do is add the cool ":" functionality
where a ":" is appended to the result if there is a result :-)  

Using %-12:(njn-get-proj-property)
doesn't work like %-12:c :-(

;; Return PROJ property or category property
(defun njn-get-proj-property()
  (or (org-entry-get (point) "PROJ" t) 
      (org-get-category)))

  (setq org-agenda-custom-commands
     '(
     ("A" agenda "" (
        (org-agenda-span 'day)
          (org-agenda-prefix-format " %-12(njn-get-proj-property) %?-12t% s")
         (org-agenda-include-inactive-timestamps nil)))

<snip>





On Wed, Sep 25, 2019 at 11:16 PM Nathan Neff <nathan.neff@gmail.com> wrote:

On Wed, Sep 25, 2019 at 7:12 PM Nathan Neff <nathan.neff@gmail.com> wrote:
Hello all,

My apologies for not finding this in the docs, but I'm trying to define a 
simple custom agenda view that is exactly the same as the default day week view,
except the only difference is displaying a property called FOO instead of the CATEGORY
property.


I found an example here:

Thanks,
--Nate
 
I think it's simply a matter of setting org-agenda-prefix-format to something
other than the default:  " %i %-12:c%?-12t% s" but I can't find the exact function to call
in place of %i.  I would think there's something like %(get-property-of-heading(FOO))

Thanks for any advice
--Nate