What I am trying to accomplish:
I want to have a point feature class named "Stations" with a child point feature class named "Valves". In field maps when you click a Station, the popup shows the associated Valves. Then selecting a Valve in the popup brings up that item, where you can then edit the Status field to On or Off.
How I've been trying to do it:
In Pro I have created two point feature classes. They both have a text field named "StationID". I've created a relationship class. (simple, one-to-many, unattributed, Station StationID as primary key, Valve StationID as foreign key) Publish as a web layer. In Online, go into the parent layer settings. turn on editing capabilities, allow to add, delete, and update. Create a map to test it out. Set up the forms in Field Maps Designer. Test it out in field maps (reloading the map every time)
Where I seem to be stuck:
In Field Maps, there is no + to add features. And when any feature is selected there is no option to edit.
You may want to ask over at ArcGIS Field Maps
It looks like related feature editing is supported in a web map so it seems like it should work. https://www.youtube.com/watch?v=D0oR2bsyFbI
I will post there.
I did watch that series of geosnaps, and it was very helpful getting me to this point.
Thanks!