Error Including QGeoPositionInfo

I am new to Qt ,

I have been given this task where i should use GPS

so to use to GPS ,i only did this one line of code

 #include <QGeoPositionInfo>

and the following error appeared

In file included from ..\Project\mainwindow.cpp:3:
..\Project\/form.h:7:28: error: QGeoPositionInfo: No such file or directory

how can i solve this issue ? how can i get this file ?

please note that i have tried re installing Qt Creator...

Please be specific i would really appreciate that...开发者_StackOverflow社区

QGeoPositionInfo is part of Qt Mobility, which is an extension to Qt.

in .pro file add:

{CONFIG += mobility
MOBILITY +=location}

2:in header add:

{using namespace QTMobility}