Have you tried:
Glib::RefPtr<Query> query =
QueryAllocation::create();
do_sth(query);
Glib::RefPtr<QueryAllocation> alloc_query =
Glib::RefPtr<QueryAllocation>::cast_dynamic(query);
It's not very nice, but if it works, it's better
than fiddling with unreference() and reference().
The obvious suggestion is to fix do_sth(). It's really odd to
require refcount==1.
Kjell
Den 2014-11-21 10:18, Marcin Kolny
skrev:
Hi,
I've got following
problem;
I've got a class Query, which is base class for QueryAllocation.
Passing \
QueryAllocation object as Query to a function is pretty simple
because of automatic cas\
ting:
void do_sth(const RefPtr<Query>&
query);
...
RefPtr<QueryAllocation> alloc_query =
QueryAllocation::create ();
do_sth
(alloc_query);
But... in do_sth method, refcount of my object equals 2 (because
casting \
increases ref count, it's obvious). Unfortunately, I have to
have refcoun\
t=1 in do_sth method, so that's what I'm doing now:
RefPtr<QueryAllocation> alloc_query =
QueryAllocation::create();
RefPtr<Query> query =
alloc_query;
query->unreference();
do_sth(query);
query->reference();
query.reset();
It's workaround.. that would be great, if I can do something
like "unmana\
ged RefPtr". It might look like this:
RefPtr<QueryAllocation> alloc_query =
QueryAllocation::create();
do_sth(RefPtr<Query>(alloc_query,
false));
And constructor declaration:
template<typename T>
RefPtr(const RefPtr<T>& src, bool manage =
true);
If 'manage' equals false, RefPtr doesn't increase/decrease
refcount durin\
g construction and destruction. I know, it's unsafe, and might
lead to a \
problems, if somebody uses it wrong, but it allows me to remove
a lot of \
magic from my code.
Of course, it's only conceptual solution, maybe it would be
better to do \
single function instead of constructor, ideas are welcome.
Best regards,
Marcin Kolny
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