Hi all,

I have a problem with a singleton, I created a singleton
with the:

 DECLARE_CLASSFACTORY_SINGLETON(MySingletonObj)

and it is ok, there is only one instance of the component
interface MySingletonObj. This way each time it is
requested an instance by COM, CoCreateInstanceEx it will
effectivelly create/return the only one instance.

The problem arises when I try to make this object global
(TopLevelObject) for easing the access from a Visual Basic
client. I created an additional interface TopLevelObject
that has a property that creates and returns an instance of
MySingletonObj (created with the "within component way"):

CComObject<MySingletonObj> *pMySingletonObj;
CComObject<MySingletonObj>::CreateInstance(&pMySingletonObj);
hr = pMySingletonObj->QueryInterface(IID_IDispatch,(void**)pVal);

this obviously bypass the Class factory and enables having several
instances of the MySingletonObj object.

Any workarounds to this problem? I don't want to renounce to the
ToLevelObject...

Thanks in advance,
Giovanni

Use CComObjectGlobal - what the singleton class factory uses.
It must be a global variable instance of course... Or if you want
the object public as well - use CoCreateInstance.

--
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Alexander Nickolov
Microsoft MVP [VC], MCSD

MVP VC FAQ: http://www.mvps.org/vcfaq
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