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Using DLLs made with MFC in a non-MFC app

We would like to be able to use MFC (VC++ 5.0) to make dlls that contain multiple Active X and standard controls and some associated dialogs. We would then need to be able to link to these dll's from other non-MFC programs
that were created by an outside company.
These other programs have well documented pre-defined interfaces that they provide to allow the use of external dll's.
We would need to make the layer that both provides the required environment for the Active X controls and maps the requests from the outside program to the appropiate functions of the Active X controls. Our dll can link to the
MFC dll and any other dll it requires.
Our dlls would typically contain a dialog that had Active X controls in it, much like a "FormView" (dialog) application.

Is this possible and practical?

If so, how do you build a simple prototype for this (for example, a simple non-MFC program that uses a dll
that has a dialog containing an Active X control)?

Since our experience with MFC dll's and Active controls is limited to the basic design methods that the AppWizard
supports, we would need a detailed example or detailed instructions on exactly how to do this.

Paul Titchener

chensu

>Is this possible and practical?
Yes, definitely.

Look into the two MFC samples that come with Visual C++.

DLLTRACE: Writes a DLL Statically Linked to the Framework Library
DLLHUSK: Dynamically Links the MFC Library

yonat

You just need to remember to call AFX_MANAGE_STATE(AfxGetStaticModuleState( )) in each of the DLLs entry points. Other than that, just do everything as usual.

titchener

ASKER

I looked at these 2 examples (DLLTRACE and DLLHUSK) but its not clear to me
that they do what we need. The first example, the dll itself seems to be built outside
the MFC IDE environment using a makefile, and it has no Active X controls.

In the second example the DLL seems to have been built using the IDE, but it doesn't have Active X controls, and its called by a program built using MFC.

Anybody interested in putting together the simple example I described above in
the original question (I'm not being lazy, I've tried to do it and can't get it to work)?

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lucidity

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titchener

ASKER

I've been trying to follow the example mentioned above (http://www.codeguru.com/dll/dialog_in_dll.shtml ). I made a MFC dll that
has two simple dialogs, one with an Active X control, one without. I also made an
MFC app that tries to bring up these dialogs by calling the function below that is
in the DLL:

extern __declspec(dllexport) void ShowNonActiveX(void)
{
      //Ensures that we are using our own resources
      AFX_MANAGE_STATE(AfxGetStaticModuleState());
      CNonActiveX dlg;
      dlg.DoModal();
}

I can step into the function, but when it executes the dlg.DoModal, I get a pop-up
dialog box with the messages:

Debug Assertion Failed:

Program: C:\testdll\debug\testdll.exe
File: afxwin1.inl
Line: 22

I get this message in either Release or Debug mode, when I try to bring
up either dialog (with and without Active X).
Any idea what I'm doing wrong here?