Qt::Window | Qt::WindowTitleHint | Qt::WindowMinimizeButtonHint | Qt::WindowCloseButtonHint | Qt::CustomizeWindowHint

setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
...
connect(QApplication::desktop(), SIGNAL(workAreaResized(int)), SLOT(setFullScreen(int)));

void MainWindow::showEvent(QShowEvent *e)
{
	QWidget::showEvent(e);
	QSize size = sizeHint();
	setFixedSize(size);
	resize(size);
	move(0, 0);
}

QSize MainWindow::sizeHint() const
{
	QRect screenRect = QApplication::desktop()->availableGeometry(QApplication::desktop()->screenNumber(this));
	QSize deltaSize = frameGeometry().size() - geometry().size();
	return (screenRect.size() - deltaSize);
}

void MainWindow::setFullScreen(int screen)
{
	if (screen == QApplication::desktop()->screenNumber(this)) {
		QSize size = sizeHint();
		setFixedSize(size);
		resize(size);
	}
}