Question

When I created a new Mobile application in Qt Creator, I noticed that in the autogenerated code they use #include <QtCore/QCoreApplication> instead of #include <QCoreApplication>, even though both should work the same.

Since Qt Creator itself does that, I assume it’s the recommended convention. But is there any reason why this is so, can someone explain what is the point to using #include <QtCore/QCoreApplication> instead of #include <QCoreApplication>?

Answer 1

There are multiple reason for using such convention :-

1. If path included in the compiler is at the directory level of QtCore then it will trace the include file QCoreApplication from there.
2. Since there are multiple version of Qt existing in same directory,it is preferred to use a convention that discards ambiguity.(Since two QCoreApplication one belonging to Qt3 and other Qt4 will mislead compiler)

I have two directories in /usr/include/

• QtCore
• Qt

both of them have QCoreApplication in them.