shopper field - dynamic change to 'required'

[ydl]

Hi,

I develop a shopper filed that in some cases is 'required'. I also add it to 'Show in cart form'.
When the user is viewing is card some checks are done and when some conditions are met I want to change the field porprty from 'optional' to 'required'...

Is this is possible?

Thanks,
Yair

Joomla 3.4.8
VirtueMart 3.0.12

[GJC Web Design]

if u have the skills yes.. would be done by JS in an over ridden components\com_virtuemart\views\cart\tmpl\default_cartfields.php