how to add a submenu to a context menu of a QTableWidget

[berlinud]

I once use

QTableWidget->setContextMenuPolicy(Qt::ActionsContextMenu);

QTableWidget->setContextMenuPolicy(Qt::ActionsContextMenu);

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but now I need a submenu in my context menu,what should I change?
best wishes,everyone!

[high_flyer]

Have a look at the QMenu doc.
Specifically QMenu::addMenu().