Created dimension feature to support straight line measurements, that I need to label in kilometers. The DIMLENGTH field, and hence the text display, is always a planar value, confirmed by comparing the Measure tool result in planar vs. geodesic. Changing the map from Web Mercator to a geographic type has no effect, nor can I use an expression to convert to geodesic, because the Arcade function LengthGeodetic requires a geometry data type, and Expression Builder doesn't contain the SHAPE field for the dimension feature I created. Any ideas about how I can get my dimensions to display the length in kilometers? Typically my distances range between 10 and 40 km.
