gSignalConnect(obj, signal, f, data = NULL, after = FALSE, user.data.first = FALSE)
gSignalHandlerDisconnect(obj, id)
gSignalHandlerBlock(obj, id)
gSignalHandlerUnblock(obj, id)
gSignalEmit(obj, signal, ..., detail = NULL)
gSignalStopEmission(obj, signal, detail = NULL)
gSignalGetInfo(sig)
f
f
will be called before or after the default handlerdata
is the first or last argument to the callbackgObjectGetSignals
.gSignalConnect
returns a numeric id for the signal handler. It is used for
blocking and disconnecting the handler.gSignalGetInfo
returns detailed information about a signal. The returned list
contains the following elements:
GType
id of the signalGType
ids for the parametersGType
id owning the signalA signal emission consists of five stages, unless prematurely stopped:
G_SIGNAL_RUN_FIRST
signals
after
flag FALSE
)
G_SIGNAL_RUN_LAST
signals
after
flag of TRUE
G_SIGNAL_RUN_CLEANUP
signals
The user-provided signal handlers are called in the order they were connected in.
All handlers may prematurely stop a signal emission, and any number of handlers
may be connected, disconnected, blocked or unblocked during a signal emission.
There are certain criteria for skipping user handlers in stages 2 and 4 of a
signal emission. First, user handlers may be blocked, blocked handlers are
omitted during callback invocation, to return from the "blocked" state,
a handler has to get unblocked exactly the same amount of times it has been
blocked before. Second, upon emission of a G_SIGNAL_DETAILED
signal,
an additional "detail" argument passed in to gSignalEmit
has to match
the detail argument of the signal handler currently subject to invocation.
Specification of no detail argument for signal handlers (omission of the detail
part of the signal specification upon connection) serves as a wildcard and
matches any detail argument passed in to emission.
Most of the time, the RGtk2 user will be connecting to signals using
gSignalConnect
. This attaches an R function (and, optionally, some
arbitrary "user data") to a specific GObject
as a listener to the
named signal.
gSignalHandlerBlock
and gSignalHandlerUnblock
provide facilities
for (temporarily) blocking and unblocking the calling of an R function in response to some signal.
To permanately disconnect the handler from the object and signal, use
gSignalHandlerDisconnect
.
A signal may be manually emitted with gSignalEmit
.
The emission of a signal may be killed prematurely with gSignalStopEmission
.
Detailed information about a signal may be introspected with gSignalGetInfo
using
ids obtained with gObjectGetSignals
.
GObject