【转帖】pure virtual function call on view destruction
 

pure virtual function call on view destruction
pure virtual function call on view destruction
hello,
i am trying to get a very simple, preview - type viewer functioning using the dd rendering classes... and i am having reasonalbe success following the creating rendering application topic in the help file.
however, on destruction of my gsdevice i am getting a pure virtual function call error reported by the visual c++ (6) debug runtime.
the code i am using (without all of the implementation detatils) is :
php code:
class fff">cicodrenderdevice fff">:
public fff">odgsbasedevicefff">,
public fff">odgicontextfordbdatabase
{
public:
fff">cicodrenderdevicefff">();
fff">virtual fff">~fff">cicodrenderdevicefff">();
fff">// the only required override.
fff">virtual odgsviewptr createviewfff">(
const fff">odgsclientviewinfofff">* fff">pinfofff">,
fff">bool benablelayervisibilityperviewfff">);
};
class fff">cicodrenderview fff">: public fff">odgsbaseview
{
public:
fff">cicodrenderviewfff">();
fff">virtual fff">~fff">cicodrenderviewfff">();
fff">// provide a method for the renderer to draw to
// this is the bare-bones requirement.
fff">void polylinedcfff">(fff">oduint32 npointsfff">, const fff">odgepoint3dfff">* fff">ppointsfff">);
};
odgsviewptr cicodrenderdevicefff">::fff">createviewfff">(
const fff">odgsclientviewinfofff">* fff">pinfofff">,
fff">bool benablelayervisibilityperviewfff">)
{
fff">odgsviewptr spviewfff">((fff">odgsviewfff">*)new fff">odrxobjectimplfff"><fff">cicodrenderviewfff">>(), fff">kodrxobjattachfff">);

return fff">spviewfff">;
}
fff">
and the call stack when i receive the error is
quote:
_nmsg_write(int 25) line 221
_amsg_exit(int 25) line 324 + 9 bytes
_purecall() line 35 + 7 bytes
impexpacadd! odrxobjectimpl<class blockholder>::~odrxobjectimpl<class blockholder>(void) + 64 bytes
impexpacadd! odrxobjectimpl<class blockholder>::`vector deleting destructor'(unsigned int) + 8 bytes
impexpacadd! odrxobjectimpl<class blockholder>::release(void) + 20 bytes
impexpacadd! odgsbaseview::erase(class odgidrawable *) + 345 bytes
impexpacadd! odgsbaseview::eraseall(void) + 283 bytes
odgsbaseview::~odgsbaseview() line 125 + 128 bytes
cicodrenderview::~cicodrenderview() line 38 + 22 bytes
odrxobjectimpl<cicodrenderview>::~odrxobjectimpl<c icodrenderview>() + 22 bytes
odrxobjectimpl<cicodrenderview>::`scalar deleting destructor'(unsigned int 1) + 22 bytes
odrxobjectimpl<cicodrenderview>::release() line 66 + 33 bytes
impexpacadd! odgsbasedevice::~odgsbasedevice(void) + 129 bytes
cicodrenderdevice::~cicodrenderdevice() line 60 + 113 bytes
i am assuming that i have missed implementing some critical function in one of my two classes, but the compiler reports no errors. i've tried to determine the right way to do this by looking at the examples, but they are much heavier and considerably differnet from the help topic, so i'm having a hard time pinpointing the exact solution.
i am using dwgdirect v. 1.09 patch 1.
any and all help is greatly appreciated.
thank you,
steven
i had this same problem and then decided to remove the odgicontextfordbdatabase as a parent of my device - moved in a separate class and passed to setupactivelayoutviews(). this crash then disappeared.
hope this helps.
regards
chudomir
hrmm.. really?
i moved the class from a base to a member (of the same class that my device is a member of) like so:
odrxobjectimpl<odgicontextfordbdatabase> m_dbcontext;
and then i changed the call to setactiveviews from:
m_spdevicewrap = oddbgsmanager::setupactivelayoutviews(&m_renderer, &m_renderer);
to
m_spdevicewrap = oddbgsmanager::setupactivelayoutviews(&m_renderer, &m_dbcontext);
and the problem persists did you perchance derive from the class explicitely override any functions? the docs imply that this should not be necessary, but you never know.
thanks,
steven
can you please tell me whether your device crashes if it does not call setupactivelayoutviews()?
regards
chudomir
as i see in my source, the database context has much longer "life" than the device one, so may be you shoud attach the database context to some other class as the cview or the cdocument derived ones?
also i create it with new operator and not as a member variable.
as you can see from the call stack, the view tries to delete a drawable, and this is probably after the context member is destroyed...
hope this helps.
regards
chudomir
ever so many thanks, it took some doing, but i got the db conext to live londer than the device and all is happy now.
thank you,
steven.
just my pennies worth :-)
i have a similar experience with bcb version 6 also exiting with pure virtual error.
problem was solved by manually setting pdb pointer to null prior to calling oduninitialize();
not certain why it works but it does.
regards
keith