Have you wanted to add a custom error validation in a form based on certain field selections?? Now you can with the new Validation gadget!!!

The Validation gadget can be used to add a form validation under certain criteria (beyond just "A required field is blank") to prevent submission or a workflow action.  Sometimes gadgets require a certain number of responses, or a field is only required if specific data is entered elsewhere in the form (otherwise it's optional), certain lookup selections aren't allowed, etc.  You can set any combination of desired criteria in the Validation rules to trigger when appropriate.

Within the Validation gadget you must first enter the desired Error Text that will display when the rule(s) for visibility are met.  And then you can add the desired rule(s) to fire that validation.  For example, in the below example the validation will display when the Sponsor selected is 'To Be Determined':

Within the form the user will see the Validation message immediately:

And if they attempt to submit the form or take a workflow action (i.e. Approve, Complete Task) without addressing the validation they'll also see the error display: