Checkbox that is required to be checked

[sverkerEsriSE]

Hi!
Due to the recent introduction of the GDPR, some of our customers wish to add a checkbox to their GeoForm apps. A checkbox that must be checked in order to send in the form.

Currently, we've tried with a field in the Feature Class that is of type boolean and has "cannot be null", however, since either 0 or 1 is not null, the checkbox can be either checked or unchecked, but still comply to the rule of "not null".

Currently, we recommend using a dropdown instead, but functionality to have "required to be checked" checkbox would be nice.