Програми для обліку

using Gtk;

class Program
{
    public static void Main()
    {
        Application.Init();
        new FirstWindow();
        Application.Run();
    }

    public static void Quit()
    {
        Application.Quit();
    }
}

using Gtk;

class FirstWindow : Window
{
    public FirstWindow() : base("Test")
    {
        SetDefaultSize(600, 350);
        SetPosition(WindowPosition.Center);

        DeleteEvent += delegate { Program.Quit(); };

        VBox vBox = new VBox();
        Add(vBox);

        StackSwitcher stackSwitcher = new() { Stack = new Stack() };

        //Stack
        {
            HBox hBox = new HBox();
            hBox.PackStart(stackSwitcher, false, false, 5);

            vBox.PackStart(hBox, false, false, 5);
        }

        //Switcher
        {
            HBox hBox = new HBox();
            hBox.PackStart(stackSwitcher.Stack, true, true, 5);

            vBox.PackStart(hBox, true, true, 5);
        }

        stackSwitcher.Stack.AddTitled(new Label("page 1"), "page1", "page 1");
        stackSwitcher.Stack.AddTitled(new Label("page 2"), "page2", "page 2");
        stackSwitcher.Stack.AddTitled(new Label("page 3"), "page3", "page 3");
        stackSwitcher.Stack.AddTitled(new Label("page 4"), "page4", "page 4");

        ShowAll();
    }
}