Probelm after porting from Qt 3.3.4 to Qt 4.2.2

[joseph]

Hai

In our application we have developed a "Chemisty Molecule Drawing Chanvas" ,with some other features.
We are now porting the application from Qt3.3.4 to Qt4.2.2.

Here am attaching my code snippet which explains our framework ( precised ). main.cpp will explain the whole thing what we are trying to achive
This is working in Qt3 , but in Qt4 it gives run time exceptions.


Could you please help me out to port the same senario in Qt4.
thanks in advance.

N:B . This code snippet will work only in Qt3.3.4 .