[gtkmm] Need your advice for glademm code

[Christof Petig <christof petig-baender de>]

Good morning Murray,

motivated by your advice I changed the connect statements in the 
autogenerated file to use virtual functions instead of the 
static_cast<>,include and friend magic.

  Original statement:

button_close->clicked.connect(SigC::slot(static_cast<class 
Artikeleingabe*>(this), &Artikeleingabe::on_button_close_clicked));

  new variant:

button_close->clicked.connect(SigC::slot(this, 
&Artikeleingabe_glade::on_button_close_clicked));

  with

class Artikeleingabe_glade
{ ...
   virtual void on_button_close_clicked() = 0;
};

  which is overloaded in Artikeleingabe.

So far it works very well. But once you connect to a signal of a custom 
widget, glade-- can not guess the signature of the virtual function to 
create. Another downside is that you cannot mark any callbacks as const.

Do you have any ideas on how to solve the problem without giving up the 
benefits of using virtual functions? My first idea was to fall back to 
the old method for custom widgets.

   Christof