To add an external library to Qt project, you should know the answer to the following questions:
how to add lib search path in qt project?
LIBS += -L d:/dev/externallib/lib -l externallib.lib
how to add header file search path in qt project?
INCLUDEPATH += d:/dev/externallib/include
how to add compiler option to qt project?
QMAKE_CXXFLAGS += -std=c++0x
The macros are added to the .pro file of the project.