How to detect if at least 3 reference-selectors are not empty?

I have a form page, where I have several reference selector dropdowns. I need to make a button visible if at least 3 dropdowns re not empty (something elected). How can it be achieved? I could call a microflow of each dropdown change event, that would check all reference selector fields, but this may impact performance and very time-consuming approach as I have many dropdowns. Is there a better solution?
1 answers

I would go for onchange nanoflow on each ref selector and a helper attribute on the dataview entity.

In each onchange check if that specific association != empty and +1 the helper attribute. If it is empty -1 (and off course don't go lower than 0)

This would mean a nanoflow per association, so maintainability is a bit lacking, but in the performance area on par I would reckon.