Qt--窗口居中显示

#include <QApplication>
#include <QDesktopWidget>

int main(int argc, char *argv[])
{

 QApplication a(argc, argv);

 QDesktopWidget *pDesk = QApplication::desktop();
 MainWindow w(pDesk);
 w.move((pDesk->width() - w.width()) / 2, (pDesk->height() - w.height()) / 2);
 w.show();
 return a.exec();
}