GtkUIManager::get_widget
GtkWidget get_widget(string
path);
This method looks up a widget by following a path. The path consists of
the names specified in the XML description of the UI. separated by '/'.
Elements that don't have a name or action attribute in the XML (e.g.
<popup>) can be addressed by their XML element name (e.g. "popup").
The root element ("/ui") can be omitted in the path.