Can not use QGLWidget.

[Teuniz]

Do you have QT+=opengl to your .pro file?

Yes, I have.
But that's not the problem. The problem is that there are no headerfiles in my Qt dir, like Qt was installed with the option "-no-opengl".

When you decompress the tarbal after downloading Qt from Trolltech, there is a dir /home/teuniz/software/Qt/qt-x11-opensource-src-4.3.1/include/QtOpenGL with all the necesary headerfiles.

After installing Qt, when I look in the dir /usr/local/Trolltech/Qt-4.3.1/include there are only the subdir's:
Qt
QtCore
QtGui
QtNetwork
QtScript
QtSql
QtSvg
QtXml

My question is: Why does the cmd "make install" copy all the necessary dirs containing the headerfiles except for the dir QtOpenGL?
I did not use the option "-no-opengl" when configuring Qt.

Regards.