In the Reference Manager dialog, select Projects at the left, and check the checkbox adjacent to the. In the Solution Explorer, right-click on References in the GTK project. Select all the projects and update them to the same Xamarin.Forms version as used by the GTK project. Select the Update tab and the Xamarin.Forms package. In the Solution Explorer, right-click the solution name and select Manage NuGet Packages for Solution. Now search for the 3.0 package or greater. Select the package and click the Install button. Select the Browse tab, and search for Xamarin.Forms 3.0 or greater.

In the Solution Explorer, right click the new GTK project and select Manage NuGet Packages. Press the OK button to create the project.

This will put the GTK project in the same directory as the other projects in the solution. Click the Browse button, select the folder containing the other platform projects, and press Select Folder. Type a name for the project with a GTK extension, for example GameOfLife.GTK. In the list of project types, choose Class Library (.NET Framework), and ensure that the Framework drop-down is set to a minimum of. In the New Project window, at the left select Visual C# and Windows Classic Desktop. In Visual Studio 2019, right-click on the solution name in Solution Explorer and choose Add > New Project. Follow these instructions to add a GTK# app that will run on the Windows desktop:

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