I recently asked this question and Doug Browning answered pretty quickly. Thanks for that.
Require one answer within group
I actually need to use this repeat group within another repeat group. I've attached a modified XLSForm to show that usage. My survey requires this case. When I add another person, the continent question is required (that's good) but, the city (1 required, up to 5) is not required. When I have one person and submit the survey, the city is required, but the constraint message is in an alert and the content is not auto-scrolled to the correct location. Worse, if I have two people and will a total of one city (one city per person should be required) then the survey is accepted.
Does anyone know how to require one city per person? Also, I prefer that the constraint is inline and not in an alert. And that the city is required when adding a new person (like the continent question).