I can not include this library to my application. Try to include it in the following way:
#include <QEvent>
#include <QKeyEvent>
However, it shows me the following error:
user \ filter \ filterofperfectpersonalized.cpp: 4: error: C1083: Do not know you can open the file include: 'QKeyEvent': No such file or directory
QKeyEvent is in the library GUI of Qt. If you do not incorporate this library into the project, you will not be able to use that class.
To include the library, simply add the following to the project:
QT += gui
It can also happen that you have something such that:
QT -= gui
With what in theory it would be enough to eliminate this line.
Greetings.