I am using drupal commerce for my client ecommerce site. For shipping methods I am using commerce_shipping, commerce_ups, commerce_usps.
Everything is working but my client wants when a user select any ups shipping service a textbox should be shown and should be required.
What I have done till now :
I have created a pane which contains a textbox using order setting. And that taexbox is showing on checkout form . But when I make this textbox as a required field than it is not possible to submit the form when user select usps or flat rate shipping services.
So how I can show a textfield on checkout form which should be required only when user select any ups shippping service.
Thanks!