Have you ever had to deal with lots of GBinding or signal connection (and therefore disconnections) on indirect objects? A classic example for this is the GtkTextView:buffer GObject property.
It’s not uncommon to find vastly broken code when it comes to this. People will g_signal_connect() and never disconnect. Slightly better is to use g_signal_connect_object(). However even that requires that one of the objects be finalized to work properly.
EggSignalGroup allows you to connect to a bunch of signals on a single target object as a group. You can connect and disconnect them simply by setting the EggSignalGroup:target property. I find this convenient because I can setup the EggSignalGroup in my instance init function, and simply set the target when it becomes available. You can even bind it using g_object_bind_property() for even less application code.
EggSignalGroup *group; group = egg_signal_group_new (GTK_TYPE_TEXT_VIEW); egg_signal_group_connect_object (group, "key-press-event", G_CALLBACK (press_event), self, G_CONNECT_SWAPPED); egg_signal_group_connect_object (group, "key-release-event", G_CALLBACK (release_event), self, G_CONNECT_SWAPPED); /* ... later on */ egg_signal_group_set_target (group, text_view); /* ... and to disconnect */ g_clear_object (&group); /* or */ egg_signal_group_set_target (group, NULL);
EggBindingGroup is similar in spirit, but for GBinding. You can create a series of delayed bindings and apply them as a set. Simply set the EggBindingGroup:source property to the GObject instance you would like to bind.
EggBindingGroup *group; group = egg_binding_group_new (); egg_binding_group_bind (group, "foo", target, "foo", G_BINDING_SYNC_CREATE); egg_binding_group_bind (group, "bar", target, "bar", G_BINDING_SYNC_CREATE); /* later on */ egg_binding_group_set_source (group, my_obj);
 g_signal_connect_object() used to be broken, but should work as expected.