PaintedWidget::PaintedWidget(QWidget *parent)
:QWidget(parent)
{
resize(400, 400);
setWindowTitle("Paint Demo");
}
void PaintedWidget::paintEvent(QPaintEvent *)
{
QPainter painter(this);
painter.setViewport(0, 0, 200, 200);
painter.fillRect(0, 0, 200, 200, Qt::red);
}