Ok I found which is the problem and I'm posting the solution as well:
There is a QT5 installation at :
/usr/lib/x86_64-linux-gnu/qt5/ (version 5.0.2)
This installation may be a part of ubuntu SDK or is build-in in Ubuntu 14.04.
Our Installation is usually at home folder. For me it was at :
~/Qt5.2.1/5.2.1/gcc_64/
The problem is that when I start a project at QtCreator it searches the first path for qml modules and other files instead of my installation.
How to fix it:
- On the top menu select Tools->Options.
- Select Build & Run and then select the Qt Version tab on the right
- There should be 2 entries here. One under auto detect and one under Manual. Keep only the one that its qmake path is from your qt installation instead of the one inside /usr/lib... I kept the auto detect one.
- Apply and now QtCreator should work.
These are my settings after the fix: