I've created a .mmpk file which contains 4 polygons on a topographic map. When I open it up in ArcGIS Pro, it looks great. On Android, the polygons show up, the map does not, and I get the following:
ArcGIS Maps SDK: Load Error: ArcGISTiledLayer
System.Net.Http.HttpRequestException
hostname nor servname provided, or not known (services.arcgisonline.com:443)
I think I somehow have to embed the map in the mmpk file, but I don't see anyway to do that in ArcGIS Pro. Can someone please help me out?
Whether to embed/include the basemap within the mmpk is typically a choice you make based on your scenario/workflow and if users will have internet connectivity on their devices in the field. For more info see Offline maps, scenes, and data | ArcGIS Maps SDK for .NET | ArcGIS Developers.
In terms of the error above, it indicates that your app cannot connect to the internet - some questions / things to investigate:
If you want to work with the content offline you may find this blog about using Esri basemap in Mobile Map Packages useful.