Matt Ward

NuGet Support in Xamarin Studio 5.4

New Feature

  • Added support for the new Unified target frameworks for iOS and Mac
    • Xamarin.iOS
    • Xamarin.Mac

More details on all the new features and changes in Xamarin Studio 5.4 can be found in the release notes.

New Unified iOS and Mac Target Frameworks

Xamarin recently announced a new Unified API for its iOS and Mac products. This new Unified API makes it easier to share code between Mac and iOS as well as allowing you to support 32 and 64 bit applications with the same binary.

To use this new Unified API you can create a new Unified project for iOS, or for Mac, using one of the project templates available from Xamarin Studio’s New Project Dialog.

Unified iOS and Mac Projects in New Project Dialog

These Unified projects now support MSBuild and use the following target frameworks:

  • Xamarin.iOS
  • Xamarin.Mac

NuGet Support for the New Unified Target Frameworks

In order to support these two new frameworks the following changes were made to NuGet.

  • Add Xamarin.iOS and Xamarin.Mac as known frameworks.
  • Make frameworks that have a name that starts with Xamarin optional when checking the compatibility of Portable Class Libraries (PCLs) inside a NuGet package with a Portable Class Library project.

With these new Unified frameworks being recognised by NuGet you can now create a NuGet package with assemblies that specifically target these frameworks. The following shows part of a .nuspec file with framework specific assemblies for iOS and Mac being copied into the appropriate target lib folder inside the NuGet package.

    <file src="lib\Xamarin.iOS\*.dll" target="lib\Xamarin.iOS10" />
    <file src="lib\Xamarin.Mac\*.dll" target="lib\Xamarin.Mac20" />

The Splat NuGet package, created by Paul Betts, is one NuGet package available from the main NuGet gallery that explicitly targets both of the new Unified frameworks.

Having the Xamarin frameworks treated as optional by NuGet allows you to install a NuGet package containing PCL assemblies into a Portable Class Library project, on a machine with the Xamarin PCL profiles registered. Without the Xamarin frameworks being treated as optional the NuGet package would fail to be installed since NuGet would find them incompatible unless the NuGet package explicitly included the Xamarin frameworks as part of its PCL profile.

Support for the new Xamarin frameworks will be available in the official NuGet from Microsoft in version 2.8.3. NuGet 2.8.3 is currently available as alpha release. Xamarin Studio 5.4 includes its own build of NuGet which has support for the new Xamarin frameworks.

Portable Class Libraries

In order to be able to install a NuGet package containing PCL assemblies, such as Json.NET, into a Unified iOS or Unified Mac project you will need to have the PCL profile XML files for Unified iOS and Mac installed on your machine.

On the Mac you can get these new PCL profile XML files by installing Mono 3.10.0, which is currently available from Xamarin Studio on the alpha and beta channels.

On Windows, since NuGet 2.8.3 is currently only available as an alpha release, there is a separate installer which will register the Unified iOS framework with the PCL profiles on your machine and will also install an alpha version of Microsoft’s NuGet Package Manager 2.8.3 into Visual Studio.