QWindow::setScreen has no effect

  QLabel* widget = new QLabel();
    widget->show();
    widget->windowHandle()->setScreen(screen);
    widget->setText("This should be shown in the screen " + screen->name());
    widget->resize(300,50);
    widget->show();

    QRect screenres = QApplication::desktop()->screenGeometry(item->text().toInt());
    widget->move(QPoint(screenres.center().x() - widget->width()/2,
                   screenres.center().y() - widget->height()/2));