MFC Extension DLL with OLE

Posted on 1998-04-20
Last Modified: 2013-11-25
I am building dialog based Dynamic Link Library.  In the dialog there are some ActiveX controls.  Everytime I call a function which is refering some of the ActiveX controls I got some assertion failure saying that the m_CtrlSite is NULL.  Please help solve this probelm.


S. Sun.
Question by:shaozhuang
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Expert Comment

ID: 1300720
If you are building shared DLL did you call AgxOleInit and AfxEnableControlContainer from DLL's InitInstance? If you are building MFC extension DLL you must call these two function insede application's InitInstance

Author Comment

ID: 1300721
I checked  Galkin idea, it did not work. I also tried using AfxLockOleControl(), it did not work either.  There are must be some ways to do it.  Could somebody help?



Expert Comment

ID: 1300722
Could you post a piece of code how you create ActiveX controls

Author Comment

ID: 1300723
Hi galkin: Thanks for the help.  The ActiveX controls reside in the dialog and I asign(using calsswizard) a name for it.  In my code I call this name for some of the subroutines. WHen I call it, it give me an error saying that the m_CtrlSIte is NULL.  Do you think I need to implement a subroutine to initialize the DLL(even I use implicit initialization.

Thanks again

S. Sun


Accepted Solution

galkin earned 100 total points
ID: 1300724
m_pCtrlSite is a member of CWnd class that is wrapper of ActiveX control. When control is created using by CreateControl function or from dialog template this member becomes not NULL. If creating control failed this member remains NULL. Your probelm I guess is that your ActiveX control(s) failed to be created by some reason. Check it. Enable OLE tracing and see output.  

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