1. void MainWindow::contextMenuEvent(QContextMenuEvent *event)
    2. {
    3.     QMenu* menu = new QMenu;
    4.     menu->setAttribute(Qt::WA_DeleteOnClose);
    6.     menu->addAction(QIcon(":/icon"), tr("create"));
    7.     menu->addAction(QIcon(":/icon"), tr("retrive"));
    8.     menu->addAction(QIcon(":/icon"), tr("update"));
    9.     menu->addAction(QIcon(":/icon"), tr("delete"));
    11.     menu->popup(QCursor::pos());
    12. }

    值得注意的是需要设置 menu->setAttribute(Qt::WA_DeleteOnClose);否则会有内存泄露。
    测试不加此属性，每弹出一次菜单，都会泄露0.1MB的内存，耗费还是比较大的.