Re: Call functions in parent from a runtime loaded DLL

From:
David Wilkinson <no-reply@effisols.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Fri, 25 Aug 2006 09:29:28 -0400
Message-ID:
<OMNs4pEyGHA.4372@TK2MSFTNGP06.phx.gbl>
Ajay Kalra wrote:

"David Ching" <dc@remove-this.dcsoft.com> wrote in message
news:D6wHg.10897$%j7.7628@newssvr29.news.prodigy.net...

"Ajay Kalra" <ajaykalra@yahoo.com> wrote in message
news:uFhkoSAyGHA.1340@TK2MSFTNGP05.phx.gbl...

I thought I tried to explained that its not an alternative. There is no
CWinApp in the main app or MFC for that matter or C++. Essentially there
is
no access to app source for plugin writers that includes header files.


You

typically program thru a type library which has pre-defined interfaces,
events, enums etc.


I don't understand the issue here. The OP said, "I am developing a


'plugin'

for a MFC-based GUI". Given this, the scheme I proposed is valid and much
lighter weight than COM automation. I'm not saying you should never use


COM

or automation, but neither would I use it as a first choice unless simpler
schemes wouldn't work for one reason or another. The OP can determine if
that's the case and act accordingly.


If I understood your suggestion, you proposed modifying source of main
application. For a plugin developer, this choice is typically not available.

--
Ajay Kalra [MVP - VC++]
ajaykalra@yahoo.com


Ajay:

Yes, if you cannot control the application code you have to make do with
what is provided. But if you can, I agree with David that a non-COM
abastract interface is the way to go. I do it exactly the way David
says, with multiple inheritance (with the MFC base class in the
left-most position).

David Wilkinson

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