How does one go about finding groups layer IDs on a rest service?
Reading about grouped and sublayer grouped layer ids via Use URL parameters—ArcGIS Web AppBuilder | Documentation but haven't sleuthed how one can deduce (from the rest service) what the unique 4 digit layer ID is????
See that the sublayer ID is the actual individual layer ids from rest service... but where does one find the grouped layer id?
Any info appreciated.