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
  • 3
  • 2

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.  

Featured Post

Courses: Start Training Online With Pros, Today

Brush up on the basics or master the advanced techniques required to earn essential industry certifications, with Courses. Enroll in a course and start learning today. Training topics range from Android App Dev to the Xen Virtualization Platform.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction: Ownerdraw of the grid button.  A singleton class implentation and usage. Continuing from the fifth article about sudoku.   Open the project in visual studio. Go to the class view – CGridButton should be visible as a class.  R…
For a while now I'v been searching for a circular progress control, much like the one you get when first starting your Silverlight application. I found a couple that were written in WPF and there were a few written in Silverlight, but all appeared o…
This video will show you how to get GIT to work in Eclipse.   It will walk you through how to install the EGit plugin in eclipse and how to checkout an existing repository.
This is Part 3 in a 3-part series on Experts Exchange to discuss error handling in VBA code written for Excel. Part 1 of this series discussed basic error handling code using VBA.…

816 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

8 Experts available now in Live!

Get 1:1 Help Now