Sets or gets the user provided primary key to assume for the data. Certain functionality of the grid requires a way to uniquely identify items in order to work correctly. If a primary key cannot be inferred from the data source, you may need to provide one here.
Target Platforms: Android 4.4+, iOS 8+
Development Environments: Visual Studio 2015+, Visual Studio for Mac Preview, Xamarin for Visual Studio 4.2+
