Re: Single toggle reference only

[Yevgen Muntyan <muntyan tamu edu>]

Owen Taylor wrote:
> On Sat, 2007-10-20 at 17:58 -0500, Yevgen Muntyan wrote:
>   
> > Hi there,
> >
> > Is there a technical reason why toggle references
> > allow only a single user? Namely, why
> >
> > " Multiple toggle references may be added to the same
> > gobject, however if there are multiple toggle references
> > to an object, none of them will ever be notified until all
> > but one are removed."
> >
> > Why doesn't it emit a notification when reference count
> > drops to N instead of 1, where N is number of
> > g_object_add_toggle_ref() calls?
> >     
>
> Say you have the following scenario:
>
>                                    GTK+ internal reference
>                                          || A
>                                          \/               
>  C# application data => C# proxy <=> [ GObject ]
>                                   B      /\
>                                          || C
>                                          \/
>                              java implementation of object
>                         
> Your suggestion is that the toggle references B and C should be 
> notified when the strong reference A is dropped. But then the
> reference to the Java object would be converted to a weak
> reference and the Java object improperly collected, even though
> it is still referenced from the C# application.
>   

But it would happen only if C# kept the object, i.e. if it
didn't drop its toggle reference. I'd think it contradicts
the purpose of toggle references; it could be banned.
Unless there is a use for toggle references other than
attaching proxies which are kind of glued to the object.

Best regards,
Yevgen