Just checked the source for 2.4.13 and 2.5.5. Both use a GtkToggleButton... Check the following "scan" function - should print a list of found object types: static void scan_children( GtkWidget *w, gpointer data ) { g_print( "%s\n", G_OBJECT_TYPE_NAME( w ) ); } For me it finds: GtkToggleButton GtkEntry About GTK_IS_... macro: There are six std macros defined by every Gtk+ "class". They are used for: 2* type checks (GTK_IS_...[_CLASS]) 2* obj casts (GTK_...[_CLASS]), e.g. GTK_BIN( my_combo )->child 1* the type system internal type (GTK_TYPE_...) 1* get the objs class (GTK_..._GET_CLASS) E.g. if you look into the code, you will find a lot of g_return_if_fail( GTK_IS_...( combo ) ); For more information read the Gtk+ tutorial and http://www.le-hacker.org/papers/gobject/ And be sure you use gtk_container_forall not gtk_container_foreach! Jan-Marek _______________________________________________ gtk-list@xxxxxxxxx http://mail.gnome.org/mailman/listinfo/gtk-list