Before you update your existing code to the Unified API, it is highly recommended that you eliminate all in the Classic API will become errors once you migrate to Unified.
Fixing them before you start is easier because the compiler messages from the Classic API often provide hints on what to update.
Updating your system You should back up your system before installation; you can use Time Machine.
For any included component, replace the current version with a new version from the Xamarin Component Store that supports the Unified API and do a clean build.
Until that time, just like the components, you'll need to switch any Nu Get Package you have included in your project to a version that supports the Unified APIs and do a clean build afterwards. Mac.dll' is referenced explicitly, while 'monomac.dll' is referenced by 'xxx, Version=0.0.000, Culture=neutral, Public Key Token=null'" after converting your application to the Unified APIs, it is typically due to having either a component or Nu Get Package in the project that has not been updated to the Unified API.
Note: If you have an error in the form "Error 3 Cannot include both 'monomac.dll' and 'Xamarin. You'll need to remove the existing component/Nu Get, update to a version that supports the Unified APIs and do a clean build. Mac mobile application that has been converted to the Unified API, the developer still needs to enable the building of the application for 64 bit machines from the app's Options. Mac Apps of the 32/64 bit Platform Considerations document for detailed instructions on enabling 64 bit builds.
Mac apps to use the new Unified API: Change the project flavor in your csproj files from Xam Mac reference similar to this screenshot (because we just changed the project type): Click the Gear Icon beside the Xam Mac entry and select Delete to remove the broken reference. If custom subclasses override these methods the signatures will no longer match and will result in errors.
Next, right-click on the References folder in the Solution Explorer and select Edit References. Fix these method overrides by changing the subclass to match the new signature using native types.
Mac application, please see our Target Frameworks documentation.