connectClosure
Connects @closure to the signal @detailed_signal on #GSignalGroup:target.
You cannot connect a signal handler after #GSignalGroup:target has been set.
Since
2.74
Parameters
detailedSignal
a string of the form signal-name
with optional ::signal-detail
closure
the closure to connect.
after
whether the handler should be called before or after the default handler of the signal.