Determines whether an accelerator that activates the signal
identified by @signal_id can currently be activated.
This signal is present to allow applications and derived
widgets to override the default #GtkWidget handling
for determining whether an accelerator can be activated.
Determines whether an accelerator that activates the signal identified by @signal_id can currently be activated. This signal is present to allow applications and derived widgets to override the default #GtkWidget handling for determining whether an accelerator can be activated.