Deprecated since since version 4.1
public event OnMnemonicActivate
the event firing control
a string encapsulating the 'group_cycling' property (undocumented in GTK)
Event fired when a mnemonic is activated(check GTK for more information).
The 'group_cycling' property is optained this way:
Warning: this event is undocumented(or poorly documented) in GTK/GTKmm.
This event can close the application by returning MSG_APPLICATION_QUIT. Any other return value will be ignored.