Daniël Mantione wrote:
>
> Op Tue, 8 May 2007, schreef Andrew Haines:
>
>> The reason for this is, I want to trick gtk into thinking that a TObject
>> is really a GObject. This is where the TypeID for GType's are stored. I
>> know this won't work for most GObject's, but I am only implementing this
>> for a GInterface which is looked up by the TypeID, so that is all I need.
>>
>> I've tested this and it is working. But what horrible things can happen?
>
> I think it is much better to use objects for this rather than classes. A
> construction like this:
>
> type gobject=object
> gobject_typeid:...;
> end;
>
> gobject_child=object(gobject)
> constructor init;
> destructor done;virtual;
> end;
>
> ... will exactly to what you want: the gobject_typeid is at offset
> 0 while the size and vmt index are stored after that.
>
type
TBaseObject=object
FGObject: TGObject;
end;
TMyObject=object(TBaseObject)
procedure MyProcedure; virtual; cdecl;
end;
This is working perfectly. I am letting gtk allocate the object's
memory, then in the instance_init func that gtk calls I am running .Init
for the object and voila! I have a real object that I can pass to gtk
and use in my program.
Thanks,
Andrew
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