How to select text as single answer on next screen

@Grzesiek2010

1. What is the problem? Be very detailed.

i want to show only those brand names in A2 for selection which are not empty in A1. i.e.
Respondent told me only two brand then only 2 brand should be shown in next screen for selection..

in current situation all brand shown on next screen which are empty

A1.Please enter brand names.
opt1._______________
opt2._______________
opt3._______________
opt4._______________
opt5._______________

A2.Favourite Brand
Opt1. select_one
Opt2. select_one
Opt3. select_one
Opt4. select_one
Opt4. select_one

2. What app or server are you using and on what device and operating system? Include version numbers.

ODK Collect, ODK Aggregate

3. What you have you tried to fix the problem?

I made 5 text type question in a group. then call them "${question}" in "label" on choices sheet.

4. What steps can we take to reproduce the problem?

file is attached for your reference
AIO.xlsx (13.8 KB)

5. Anything else we should know or have? If you have a test form or screenshots or logs, attach below.

Unfortunately, I think it's not possible to do that in that way. My first thought was to add something like label!='' to choice_filter but we can't filter such dynamic values in the choices sheet.

How about replacing your 5 questions with a repeat group and then build choices based on that group? The form would be similar to the one I attached here: Dynamic choices from repeat - #2 by Grzesiek2010 would that work for you? If so you could for example add constraint
so that the answer can't be empty in a repeat group and your users would just add as many groups as they want for example 2 or 3 not 5 as you have now (the number of question).