I have a problem serializing and reading back a QMap that holds a collection of my class called PID.

In this class I implemented operators << and >> as below, with the help of some good fellas here in this forum.
Qt Code: 
  1. QDataStream &operator <<(QDataStream &out, const PID &pid)
  2. {
  3.     out << pid.getKp() << pid.getKi() << pid.getKd();
  4.     return out;
  5. }
  6.  
  7.  
  8. QDataStream &operator >>(QDataStream &in, PID *pid)
  9. {
  10.     double kp;
  11.     double ki;
  12.     double kd;
  13.     in >> kp >> ki >> kd;
  14.     pid = new PID();
  15.     pid->setKp(kp);
  16.     pid->setKi(ki);
  17.     pid->setKd(kd);
  18.     return in;
  19. }
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Latter the map is serialized like this
Qt Code: 
  1. PID pid;
  2.     pid.setKp(34);
  3.     pid.setKi(45);
  4.     pid.setKd(54);
  5. QString path = appDir.path() + QDir::separator()
  6.             + name + TXT_FILE_EXT;
  7.     QFile pidFile(path);
  8.     pidFile.open(QIODevice::ReadWrite);
  9.     QDataStream stream(&pidFile);
  10.     QMap<quint8, PID*> pidList; 
  11. stream << pidList;
  12.  
  13.     pidList.clear();
  14.     stream.device()->reset();
  15.  
  16.     stream >> pidList;
  17.  
  18.     qDebug() << "Pid map size: " << pidList.size() << " File Size: "<< pidFile.size();
  19.     pidFile.close();
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when I run this I get the same "Pid map size: 0 File Size: 8 " even when the map's size is changed in the code. Any Idea how I can get to my goal of serializing the collection of PIDs to a file and read back?
Thanks.