I'm using the standard basemap gallery and am getting all of the standard Esri basemaps. I want keep those, but also add a custom map service basemap that is saved on my ArcGIS Online account. How do I do that?
I see here how you can set the source for your basemap gallery. I tried that in this codepen, but it didn't see to do anything. I want to be able to specify a specific map service. How do I do that?