qt中设置菜单高度

如题所示，我建立一个菜单，代码如下，但是菜单项的高度太小了，
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popupMenu = new QMenu(this);
QAction *action1 = new QAction(tr(“&New1”), this);
QAction *action2 = new QAction(tr(“&New2”), this);
QAction *action3 = new QAction(tr(“&New3”), this);
QAction *action4 = new QAction(QIcon(“./load.png”), tr(“Bookstore”), this);
popupMenu->addAction(action1);
popupMenu->addAction(action2);
popupMenu->addAction(action3);
popupMenu->addAction(action4);
popupMenu->exec();
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