COM / DLL / ActiveQt

paulanon

Sadly new to Qt and COM/DLL. But ActiveQt to save the day!? Sadly, I can't find good examples for loading a DLL dynamically (when needed) in my C++/Qt program and calling functions in the DLL (parameters and return values). Much appreciate guidance. Thank you.

Franzk

The "QLibrary":http://doc.qt.nokia.com/latest/qlibrary.html documentation is actually pretty good.

Just for finding a bunch of C functions in a library you don't need ActiveQt. Use ActiveQt just for COM or ActiveX components.

paulanon

To clarify my question, if I have a dll that is COM/Activex and I want to call the functions, I can use the resolve function in QLibrary? That sounds less painful, but still not clear how I can do that without given the header file associated with the dll; I do have documentation with it. Thank you.

Edit: This dll is used for reading in a proprietary file format. So, it's not a simple function call (like a math function). I need to connect to the dll, open the file through a function in the dll, then call various functions to access data through the dll, close the file, and disconnect from the dll.

Franzk

I've never tried to actually use a COM object in a C/C++ project. Did you actually look through the "ActiveQt Container documentation":http://doc.qt.nokia.com/latest/activeqt-container.html?

paulanon

I've quickly looked through it. I wish there were some sample code to get me started. But yes, I should definitely look at the doc more carefully.

Franzk

How about the "ActiveQt examples":http://doc.qt.nokia.com/main-snapshot/examples-activeqt.html?

paulanon

Thank you for looking into this. But I believe all of them are for creating an activex component, not using it.

Franzk

The Qutlook example uses the Outlook COM object.

paulanon

I feel silly. That was the ones I didn't bother looking. Yes, it does use COM, but it doesn't seem to be calling the DLL directly. I'll need to look at what msoutl.h/cpp contains.

paulanon

Just in case you're interested, I've gotten a bit further. New thread posted here:
http://developer.qt.nokia.com/forums/viewthread/9957/