Re: gobject weak references

[Sven Neumann <sven gimp org>]

Hi,

Murray Cumming <Murray_Cumming betaresearch de> writes:

> 1.
> Is this an accurate description of the new gobject weak references
> mechanism?:
> It doesn't actually increase the refcount, so the object might be
> deleted, but you'll know if it does because it will call your callback
> function.

sounds good to me.

> 2.
> The GWeakNofify callback will have this signature:
> void weaknotify_callback(gpointer data, GObject *where_the_object_was);
> What is the second argument about?

it is the memory address of the GObject that has been destroyed. You should
never dereference this pointer since it does not point to a valid GObject
anymore, but there are cases where you need this pointer. One example is
that you have a list or hash of GObjects and you want to remove the pointer
from this list when the GObject gets destroyed. You can very simply 
implement such a weak container by adding a weak reference to the GObject 
whenever you add one to the list and have it removed from the list in the 
weak notifier.


Salut, Sven