Choice Callback Setup

(pasted from other forums)

Hi,

I’m looking for help with “Choices Callback”, I’m trying to setup a registration form via Ultimate Member.

Problem/Example: I have to sort my users by “Zones” (user role) based off their state, when a user uses the registration form they have to fill out their address. So for example when a user picks “Mississippi” as their state, a role selection dropdown will pre-populate the zone that correlates to “Mississippi”.

I have found example code, but I’m confused or doing something wrong. If someone could show me what to replace in the example code, would be great!

https://gist.github.com/dave-mills/8dbaaffbfb016fcf4a9f8ecc50e89e5e

Thanks