why we have need of QApplication

[nupul]

do the following:
1. Read the docs
2. I feel your constructors are not in the correct form:

QFont ()
QFont ( const QString & family, int pointSize = -1, int weight = -1, bool italic = false )
QFont ( const QFont & font, QPaintDevice * pd )
QFont ( const QFont & font )

QFont ()
QFont ( const QString & family, int pointSize = -1, int weight = -1, bool italic = false )
QFont ( const QFont & font, QPaintDevice * pd )
QFont ( const QFont & font )

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These are from my qt4 doc...i don't think this has changed since qt3...but you can confirm

3. Read a Qt book...whenever you create a QApplication obj, you also need to call show and exec functions:

//include files
 
int main(int argc, char *argv[])
{
   QApplication app(argc, argv);
 
// your code...
 
  app.show()               //actually shows the app window on screen!
 
  return app.exec();       //you don't return 0, when using Qt!!
}

//include files

int main(int argc, char *argv[])
{
   QApplication app(argc, argv);

// your code...

  app.show()               //actually shows the app window on screen!

  return app.exec();       //you don't return 0, when using Qt!!
}

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4. you are creating font etc objs on the stack....thus you need to pass them by reference to the constructors above and not by value.

5. You "seldom" need to use C++ in its true form with Qt...eg when you wish to use "cout" etc...try understanding qt and recoding ur prog...

6. If there is no harm upgrade to qt4! please

7. enclose your code in [ code] [ / code] blocks

8. comment your code!!