Function

GObjectSignalAccumulator

Declaration

gboolean
(* GSignalAccumulator) (
  GSignalInvocationHint* ihint,
  GValue* return_accu,
  const GValue* handler_return,
  gpointer user_data
)

Description

The signal accumulator is a special callback function that can be used to collect return values of the various callbacks that are called during a signal emission.

The signal accumulator is specified at signal creation time, if it is left NULL, no accumulation of callback return values is performed. The return value of signal emissions is then the value returned by the last callback.

Parameters

ihint

Type: GSignalInvocationHint

Signal invocation hint, see GSignalInvocationHint.

The data is owned by the caller of the function.
return_accu

Type: GValue

Accumulator to collect callback return values in, this is the return value of the current signal emission.

The data is owned by the caller of the function.
handler_return

Type: GValue

A GValue holding the return value of the signal handler.

The data is owned by the caller of the function.
user_data

Type: gpointer

Callback data that was specified when creating the signal.

The argument can be NULL.
The data is owned by the caller of the function.

Return value

Type: gboolean

The accumulator function returns whether the signal emission should be aborted. Returning TRUE will continue with the signal emission. Returning FALSE will abort the current emission. Since 2.62, returning FALSE will skip to the CLEANUP stage. In this case, emission will occur as normal in the CLEANUP stage and the handler’s return value will be accumulated.