objects. In fact, it makes little sense to have your registration
I can't create an insternal instance of my object.
I have a capture card that can only be accessed by one app
at a time, and we need the video in several places.
So I wrote a COM (out-of-proc) Service that
when it is created, starts grabbing frames from the capture
card and hands them to the programs that implemented
instances of the object through events. Then if
another app creates an instance, it starts handing the
new app frames. I want to register the category so the
applications can choose which capture card frame server
to create an instance of by enumerating installed COM
"Frame Servers". The application and frame servers
are already working fine. I can open up 6 applications
that CoCreate my frame servers, and they all get and
display video fine. I just need to have a way to
enumerate installed frame servers. I can simply do
this through the registry, but since we've been using
categories for some time to state what of our software
is installed, I was following our convention. The rest
of our objects are housed in DLLs (in-proc) though.
Steven
"Alexander Nickolov" <agnickolov@mvps.org> wrote in message
news:uvdQtSFdGHA.3388@TK2MSFTNGP05.phx.gbl...
If I read this correctly, you use the COM runtime to create
an instance of a COM object serverd by your module, am I
right? Besides being wasteful, note this may not work in an
executable since you don't register a class object during
registration. COM has to start a new instance of your EXE
server to provide your object (assuming its registration has
passed already, but otherwise your DLL wouldn't work either).
Then the interface must have marshaling support and here's
where you most likely fail (another possibility is you not allowing
multiple instances of your executable running simultaneously).
I'd suggest you simply create an internal instance of your object
without going through the COM runtime.
--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@mvps.org
MVP VC FAQ: http://www.mvps.org/vcfaq
=====================================
"Steven Edison" <EdisonCPP@newsgroups.nospam> wrote in message
news:%238oWh2EcGHA.3348@TK2MSFTNGP03.phx.gbl...
I'm creating several catagories to house my company's functionality, so
we can enumerate these on a machine to see what's available.
For the longest time, this has been working fine with my ATL (in-proc)
DLLs, using RegisterClassImplCategories, however, now I'm trying to use
it on an (out-of-proc) service, and RegisterClassImplCategories returns
S_OK, but OLE/COM Object Viewer doesn't display the addition.
Futhermore, I manually went to the registery and added the Implemented
Categories key, and vuala, it showed up in the viewer. I recompiled
which, of course, reregistered it, running through my
RegisterClassImplCategories() again, and it removed my registry entry,
while still returning S_OK.
I have a wrapper interface that handles the naming convention of my
categories, here's the code for the RegisterClassImplCategories()
function call:
//Simple function that really just calls RegisterClassImplCategories()
STDMETHODIMP CProCatRegister::RegisterClassInCategory(REFCLSID clsid,
GUID catid)
{
RPC_STATUS status;
if(::UuidIsNil(&catid, &status)) return DISP_E_PARAMNOTOPTIONAL;
if(::UuidIsNil((UUID*)&clsid, &status)) return
DISP_E_PARAMNOTOPTIONAL;
HRESULT hr = E_FAIL;
if(FAILED(m_hrCreate)) return m_hrCreate; //Checks that
m_pCatRegister was created properly in constructor
if(m_pCatRegister)
{
CATID Catid[1] = { catid };
hr = m_pCatRegister->RegisterClassImplCategories(clsid, 1,
Catid);
}
return hr;
}
Then in my ATL service's RegisterAppId() function for registering the
service:
HRESULT RegisterAppId(bool bService = false)
{
HRESULT hr = __super::RegisterAppId(bService);
if(SUCCEEDED(hr))
{
CComPtr<IProCatRegister> pCatReg = NULL;
if(SUCCEEDED(pCatReg.CoCreateInstance(CLSID_ProCatRegister)))
{
hr = pCatReg->RegisterCategory(CATID_VideoSource,
(char*)szVideoSrcName); //works fine
if(FAILED(hr)) return hr;
hr =
pCatReg->RegisterClassInCategory(CLSID_ReceiveFrameContainer,
CATID_VideoSource);
if(FAILED(hr)) return hr;
}
}
return hr;
}
Any ideas why all of this works fine for my ATL DLLs, but not this
service? Thanks.