In Pro 2.4, when setting a (Long Integer) Subype as the Display Field -> Map Tip, on mouse-over, the Map Tip is displayed as the code, not the description. In Arc Map this works correctly, why not in Pro?
I don't have any subtyped data at hand, but I did a quick test with domains. With no manipulation, you're right that the map tip displays the coded value.
I used the DomainName function to have the map tip display the description Data Functions | ArcGIS for Developers
Maybe try the subtype option of the Arcade function:
It doesn't appear, from that help page, that the same capability exists for subtype codes and values. I tried DomainCode($feature, 'FCSUBTYPE') and got invalid expression.
There is this: Subtype functions in Arcade
I realize this would be a workaround, but would you be able to create a domain to apply to the FCSUBTYPE field using the same codes and descriptions used for the subtype? Then, by using the arcade DomainName function, the map tip would return the description (of the domain, not the subtype, but it would be the same description as the subtype)...
Unfortunately not in this case. We have a few feature classes that depend on subtypes, and a fewer that use the subtype as the primary display/symbology attribute. Flipping those to domains removes the ability to use subtypes to manage different editing workflows, and duplicating the subtype as a domain isn't in the cards. I'll probably open a case on this.
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