Can't set custom GtkWidget style property in gtkrc

[Stefan WEBER <stefan weber wanadoo fr>]

Hi all,

I wish to add a style property to GtkWidget in order to retrieve it in several derived gtkmm-classes.

In main() I do the following:

    gpointer p = gtk_type_class(GTK_TYPE_WIDGET);

    gtk_widget_class_install_style_property (GTK_WIDGET_CLASS(p),
                                             g_param_spec_int ("my-custom-int",
                                                               "my int",
                                                               "my custom integer",
                                                               0,
                                                               G_MAXINT,
                                                               8,
                                                               (GParamFlags)G_PARAM_READWRITE /*was READABLE, 
but doesn't change anything*/));

    gtk_rc_parse("./gtk-2.0/gtkrc");


In gtkrc:

   style "default"
   {
   # colors to verify that the style is applied
           fg[NORMAL]                                                      = "#FF0000"
           text[NORMAL]                                                    = "#FF0000"

           GtkWidget::my-custom-int=4
   }

   class "*" style "default"


Example of derived classes:

   class MySpinButton:public Gtk::SpinButton
   {
      ...
   }

   MySpinButton::MySpinButton(BaseObjectType* cobject, const Glib::RefPtr<Gnome::Glade::Xml> &refGlade)
    :Gtk::SpinButton(cobject)
   {
      Glib::Value<int> my_int;
      my_int.init(G_TYPE_INT);
      get_style_property_value("my-custom-int",my_int);
      cout << "my_int = " << my_int.get() << endl;
   }

The output is "my_int = 8", not 4, so I get the property, which proves to me that it is not a GTKMM-Problem, 
but I can't set its value in gtkrc.
So, what is wrong with this? Any ideas?

Thanks in advance,

Stefan