GroupJive Events custom fields

And how would you design the code field to output a same drop down as the single select query field ?

You'd have to query for the same information using PHP then loop the resulting array. Now you'll be able to process the params columns and convert the stored integer value to text. Why does this need to be a profile field? Not sure I understand the purpose of the field.

Well I use events as marketing events. Then users subscribe to several events at the same time.
When they make new hotspots with my application they link an event to this hotspot which is then displayed on the hotspot page.
So I need a field for them to quickly select the subscribed event of their choice for the hotspot they made at a given time.
Hope you understand
If you want you can download the app and try, it's called Cercle Business on iOS or android stores

If you have a better idea than a profile field for the same result I 'd be glad to have it

No idea how to help you in regards to integrating with your app, but a code select would be the only option since there's no functionality to customize the option label and group display beyond specifying what column they're from. Best I could do is maybe add support for customizing those with a substitution supported output so you could use IF substitutions to condition the group from their integer values to string values.

forge.joomlapolis.com/issues/7843

I think that it's a really good idea because code field is not really easy to use for outputting the dropdown

You can now customize the label and group display with substitution supported string in latest CB Query Field build available now. You should see the new parameters under the label column and group column parameters.