Russian Qt Forum

 void paintEvent(QPaintEvent *event)
    {
        QPainter painter(this);

        QPen blackpen( Qt::black );
        blackpen.setWidth(1);
        QPen greenpen( Qt::green );
        blackpen.setWidth(1);

        QBrush br( Qt::white );

        painter.setPen(blackpen);
        painter.setBrush(br);
        painter.drawRect(QRect(50, 50, 200, 200));
        painter.setPen(greenpen);
        QRect rct(50, 100, 200, 100);
        painter.drawRect(rct);
        painter.setPen(blackpen);
        painter.drawLine(50, 50, 250, 250);
        painter.drawLine(50, 250, 250, 50);
        painter.drawLine(50, 150, 250, 150);
        painter.setPen(greenpen);
        painter.drawLine(150, 150, 250, 100);
        painter.drawLine(150, 150, 50, 100);
        painter.drawArc(rct, 45 * 16, 90 * 16);
    }