help regarding circle

i developed one Gui using Qt designer in windows.the steps what i did are mentioned below,
step1: i have taken main window.

step2:i placed the tab widget in the mainwindow from qt designer widget list.

what i need exactly is, the circle which is able to display on my tab widget.

for this, i developed some code,by this i am able to display the circle on mainwindow,but i cant display the circle on tabwidget.

in mainwindow.cpp: (i defined function of circle like this)

void MainWindow:: paintEvent(QPaintEvent *event)
{

QPainter painter(this);
painter.setRenderHint(QPainter::Antialiasing, true);
painter.setPen(QPen(Qt::black, 1, Qt::SolidLine, Qt::RoundCap));
painter.setBrush(QBrush(Qt::green, Qt::SolidPattern));
painter.drawEllipse(190, 30, 30, 30);
}

in mainwindow .h: (where i called the circle)

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include "ui_mainwindow.h"
class MainWindow : public QMainWindow, public Ui::MainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = 0);
void paintEvent(QPaintEvent *event);

};
#endif


i need to display circle in the tabwidget,plz kindly help me,

thanx in advance.

Reimplement paintEvent() of the widget you want to draw on. If you want to draw on QTabWidget, reimplement its paintEvent() instead of main window's. If you want to draw on a page of tab widget, reimplement its paintEvent().

first thanks for ur kind response.

If you want to draw on QTabWidget, reimplement its paintEvent() instead of main window's.
in my code where i want to change.i tried in many ways but am not getting,plz provide some detailed explanation about this issue.i am totally getting confused with this.
thanks in advance.