Call my function in PDF form created by Writer?

[kumuseki]

I need to create writable PDF forms with the OpenOffice Writer. With the form controls, I can begin to get along. Now gimmicks start

I have a list box. Select a month there e.g. September 2020. The number of working days in this month should then be entered in another text field. I know from experience that many of my colleagues are intellectually overwhelmed by this. So I'm looking for something like an if-then function. If September 2020 was selected in the list field 1, the number 22 should appear in text field 1.

Is that possible? And if so: how?

Edit: SPAM removed, topic locked -- MrProgrammer, forum moderator

[RoryOF]

There is a full set of macros for manipulation of list boxes in every Writer document; these are at /Tools/ /Macros //OpenOffice Macros /Organize Macros /OpenOffice Basic //Tools /Listbox

Enjoy yourself!