I have an inheritance tree like :

Qt Code: 
  1. BaseClass : QObject {
  2.    Q_OBJECT
  3.    // etc..
  4. } ;
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Qt Code: 
  1. ChildClass1 : BaseClass {
  2.    Q_OBJECT
  3.    // etc..
  4. } ;
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Qt Code: 
  1. ChildClass2 : BaseClass {
  2.    Q_OBJECT
  3.    // etc..
  4. } ;
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And for each class I declared and defined default constructor, copy constructor, assignment operator overload, and friend << and >> operators for QDataStream support.

Now, I have a list of BaseClass pointers used as follow :
Qt Code: 
  1. void saveData(QDataStream & stream)
  2. {
  3.    QList<BaseClass*> objList ;
  4.    objList.append( new ChildClass1() ) ;
  5.    objList.append( new ChildClass2() ) ;
  6.    stream << objList.length() ;
  7.    foreach(BaseClass *obj, objList)
  8.    {
  9.       stream << (*obj) ;
  10.    }
  11. }
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So when I serialize this list, how do I make sure it's actually ChildClass1 or ChildClass2 instances beeing serialized ? stream operators are non-member functions, so they cannot be virtual.

The same way when I de-serialize objects, (I must be blind but) I'm stuck with the following :
Qt Code: 
  1. void readData(QDataStream & stream)
  2. {
  3.    int i, count ;
  4.    QList<BaseClass*> someList ;
  5.    stream >> count ;
  6.    for(i=0; i<count; i++)
  7.    {
  8.       stream >> ...// now what do I do here ?
  9.    }
  10. }
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Long story short, how do I combine Qt serialization and class inheritance ?

Any pointer would be greatly appreciated