In web appbuilder, legend widget works fine with map service.
Now I have a gp service, which creates a categorical raster. I can see its legend at server. I can add the raster as a result map service to client with Javascript API. But there is no legend for the result in legend widget.
I'm wondering this is an issue of legend widget, or I should take some special steps to make the result map service come along with its legend.
Any clue will be appreciated very much.