I am new to Xamarin, so please be kind....
I created a Solution which contains Shared Project & 2 platform-specific Projects: Android and iOS. I can clean & build each project individually.
However, when I perform Clean All followed by Build All, the shared code is not rebuilt and both Project builds fail (link errors). But If I select the shared portion of the project, build it, then build either iOS/Droid project, they build and link just fine.
It seems there is no dependency of the platform-specific projects on the shared code. I'm thinking it's a setting in Build Options, but I don't see anything.