[gtkada] gtk ada newbie question

[alfonso_acosta_mail at yahoo.es]

hi:

Im sure Im commiting some newbie faults cause Im new to GUIs and gtkada,
I just want to see how a window appears with a colored backgroung using
gtk.extra.plot, here is the code
-------------------------------------------------------------------------
with Gtk.Main,
   Gtk.Window,
   Gtk.Extra.Plot,
   Gtk.Box,
   Gdk.Drawable,
   Gdk.Color;

procedure Plot is
    Window      : Gtk.Window.Gtk_Window;
    Vbox        : Gtk.Box.Gtk_Box;
    Plot        : Gtk.Extra.Plot.Gtk_Plot;
    Dibujo      : Gdk.Drawable.Gdk_Drawable;
    Color       : Gdk.Color.Gdk_Color;
begin

    Gdk.Color.Set_RGB( Color, Red => 13, Green => 123, Blue => 198);

    Gtk.Main.Init;
    Gtk.Window.Gtk_New (Window);
    Gtk.Window.Set_Title (Window, "Funcionara el plot?");

    Gtk.Box.Gtk_New_Vbox (Vbox, Homogeneous => False, Spacing => 0);
    Gtk.Window.Add (Window, Vbox);

    Gtk.Extra.Plot.Gtk_New (Plot, 200.0, 200.0, Dibujo);
    Gtk.Extra.Plot.Set_Background(Plot, Color);
    Gtk.Box.Pack_Start(In_Box => Vbox, Child => Plot);
    Gtk.Extra.Plot.Show (Plot);

    Gtk.Window.Show (Window);
    Gtk.Main.Main;



end Plot;
--------------------------------------------------------------------------

What am I doing wrong?

Thanks in advance:

Alfonso Acosta