Connects a callback to a signal for a particular object.
The handler will be called before the default handler of the signal.
the instance to connect to.
a string of the form "signal-name::detail".
the callback to connect.
a combination of ConnectFlags.
the handler ID, of type gulong (always greater than 0 for successful connections)
Connects a callback to a signal for a particular object.
The handler will be called before the default handler of the signal.