[gtkmm] Q: How to dynamically change label and callback of a Gtk::MenuItem at runtime?

[Mirco Müller <mirco mueller post rwth-aachen de>]

Greetings everybody!

	Well, the subject asks it all. I'm trying to figure out how to
correctly change the callback and label of an already created
Gtk::MenuItem. At the moment it looks like I have to completely replace
the Gtk::MenuItem with a new one.

Thanks in advance for your time and kind advice!

Best regards...

Mirco