Validation only if another field is present

Hi there, how would I create a validation required if a another field has data?

So for example, if data field 1 has an entry, then data field 2 is required, if data field 1 is is empty, then data field 2 show an error message.

Thank you.

Hey Saffa. I think to achieve this you could use the App Framework. You could build a Field app for the field that should show validation.