I'm trying to finish the add layers to map tutorial (Add layers to a map | ArcGIS for Developers) but despite following it exactly the layer isn't showing up. The basemap added in the previous tutorial is fine and I'm not getting any errors, it just isn't there. I've also tried adding a layer I created and uploaded myself and still nothing. Any ideas?
Editing to add: I'm able to add my layer using the item ID (with these instructions Add a layer from an item | ArcGIS for Developers) but it seems a lot more complicated.