Grab current selection from a google form section

Question

I have a google calendar that lists multiple free classes that are available each month. Currently the way people sign up is that they click on a link to a google doc and enter their names, but a blank work doc with names isn't very professional. Instead I'm created a google form that will send the responses to an excel spreadsheet, but need some help.

Currently the form first question asks "what date is the class you'd like to addend?" - Is there any way I can get the users response to that first question without having them submit the form?

Essentially I'd like for them to enter the date and use the getEventsForDay(date) function to create the second question dynamically populated with the calsses for the date they selected. Then have them choose the class with radio buttons. Is there any way to do this or would I have to have them select a date and then from that submit spawn a new on the fly form that then would list the classes for the date they selected?

Answer 1

For what I know you can't do that in a single form. You will need to do it with 2 forms. You can prefill the other form with some informations of the first form to make the bond.
But the best solution is: not to use the Google Forms and build your own form in apps script. Here an example and the code here.