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The question as it stands is probably unanswerable; you'll probably end up with a list of people's interpretation of "framework" with no real way for distinguishing them.
Perhaps we need a definition of framework? I suggest it is a library that in some way determines the architecture of an entire application. However that is perhaps a definition of "Application Framework", but if you mean the term more broadly, then the question is probably too broad. This definition however makes say Qt a framework, while Boost remains just a library. That makes Boost no more or less useful, so I really don't understand what you are trying to discover from the question.
Here's a list of UI related libraries that might be considered "frameworks":
The most notable distinguishing feature is that some of them are cross-platform, and some are platform specific. Gnome is perhaps distinguished by having a C API (GTK+). .Net supports multiple languages, but requires C++/CLI rather than ISO C++ (but that is no worse than Qt's pre-processor IMO). MFC is a bit long in the tooth and not supported by free or third-party tools. TurboVision is antique and included for my amusement and geek nostal