Problem solved......Inside my class i added QGraphicsScene pointer (scene) and made it to point to parent class member function scene()..Then i added one line inside paint()

the code :

Qt Code:
  1. void Text_Display::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
  2. {
  3. painter->setFont(font);
  4. painter->setPen(pen);
  5. painter->drawText(pos.x(),pos.y(),text);
  6. scene->update(); // Just this line
  7. }
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Now my text is getting updated as i wish...

Thanks for ur help...........