Hands-On GUI Programming with C++ and Qt5

Platform-specific settings

You can set different configurations or settings for different platforms, since not every setting can fit all use cases. For example, if we want to include different header paths for different operating systems, we can do the following:

win32:INCLUDEPATH += "C:/mylibs/extra headers" 
unix:INCLUDEPATH += "/home/user/extra headers" 

Alternatively, you can also put your settings in curly braces which behave like the if statements in a programming language:

win32 { 
    SOURCES += extra_code.cpp 
} 

You can check out all the settings you can use in your project file by visiting the following link: http://doc.qt.io/qt-5/qmake-variable-reference.html.