Adding a control to the OS file selector is possible under most operating systems, but wxWidgets does not give us a handle to the dialog, so there is no going. The only way to show anything different than the standard thing, you have to write your own.
You use standard file selector? Ugggrrrh.
You're right, I really don't know anything about wxWidgets.
But, then , if it's so hard to do stuff like that, then it was a really bad move to choose that framework, and I'm glad I don't know anything about it.
This is usually considered to be a very easy task.
So far , I've been working in Qt, GTK+ , VCL , CLX , MFC and Swing.
Qt is free , cross-platform and works with C++ .
In all of them, making such functionality ( without plugins ) is trivial.
If you can't make a new Form window, put a few buttons on it, and connect them with events,
and to call it with form->showModal() , there is nothing to discuss.
I don't work with interface much, I work with server apps,
but I would need 60 minutes max, to create such window with frameworks mentioned.
And that's making the completely new form.
I'm not going to debate over this anymore. If it's hard to do it , and you know wxWidgets better than me ,
just put it somewhere in somewhere in TODO list.
Thanks for your time, anyway.