multi level menu popup

I want to have a multi level context menu popup when I right click
in myWidget.

Right clicking shows 'Display', which when moved to with the cursor
then shows the option menu items...

Display >
Option 1
Option 2
Option 3

I've got the 'Display' to popup, but how to I get the second
level of popup?

Devices_table->setContextMenuPolicy( Qt::CustomContextMenu );
m_Columnmenu = new QMenu( this );
m_ColumnDisplayAction = new QAction(tr("Display"), this);
m_Columnmenu->addAction( m_ColumnDisplayAction );

Mark

QMenu::addMenu():

Code:

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m_Displaymenu = m_Columnmenu->addMenu(tr("Display"));
m_Displaymenu->addAction("...");

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