Shortcut of QAction in contextMenu has no response

[sonichy]

connect(ui->listWidget, SIGNAL(customContextMenuRequested(QPoint)), this, SLOT(customContextMenu(QPoint)));

void MainWindow::customContextMenu(const QPoint &pos)
    QAction *action_rename;
    QList<QAction *> actions;
    ......
    action_rename = new QAction(this);
    action_rename->setText("重命名");
    action_rename->setShortcut(QKeySequence(Qt::Key_M));
    actions.append(action_rename);
    ......
    foreach(QAction *action, actions){
        action->setShortcutVisibleInContextMenu(true);
    }

    QAction *result_action = QMenu::exec(actions, ui->listWidget->mapToGlobal(pos));
    ......
    if (result_action == action_rename) {
        ......
    }
}