void g_signal_override_class_handler ( const gchar* signal_name, GType instance_type, GCallback class_handler )
Overrides the class closure (i.e. the default handler) for the
given signal for emissions on instances of
instance_type must be derived from the
type to which the signal belongs.
g_signal_chain_from_overridden_handler() for how to chain up to the
parent class closure from inside the overridden one.
Available since: 2.18
This function is not directly available to language bindings.
The name for the signal.
The data is owned by the caller of the function. The value is a NUL terminated UTF-8 string.
The instance type on which to override the class handler for the signal.