I finally figured out what was wrong with my references in my iOS project!
Once I uninstalled OxyPlot.Xamarin.Forms, and installed the new 707-alpha PR, it was for “some reason” (actually a very good one, which you’ll see later) still referencing the Classic iOS OxyPlot.Xamarin.Forms API.
I was frustrated by this fact, since, when I created a new project, this was not an issue at all. This got me thinking.
Once upon a time, when I started my project, I was running Xamarin.Forms 1.2.3, and I have by now simply upgraded to the newest version (1.3.1.6296). I did some refactoring of my classes based on the post below, and thought that I was now running the Unified API:
http://www.infinite-x.net/2014/10/09/xamarin-forms-1-3-0-preview-formapplication/
Alas, upon further investigation, I found , that I had in fact NOT upgraded to the Unified API in my .csproj file:
http://developer.xamarin.com/guides/cross-platform/macios/updating_ios_apps/#Steps_to_Update_Manually
I followed the steps, removed OxyPlot, re-installed the 707 OxyPlot.Xamarin.Forms PR from the NuGet Package Manager Console.
Hereafter, everything worked as expected, and I could finally include the OxyPlot.Xamarin.Forms package for the Unified iOS project as described in the OxyPlot documentation: http://oxyplot.org/documentation/hello-xamarin-forms
// David