Nav Drawer
EuiNavDrawer provides a side navigation feature that is complete with interactions and a mobile-friendly design. It can contain one or more EuiNavDrawerGroup components and is designed to be used in conjunction with EuiHeader.
Note about displaying flyout menus
Providing a flyoutMenu prop on the listItems object of an EuiNavDrawerGroup will result in that link opening a secondary menu. Note that this will also override the onClick event. See sample data in the Demo JS tab.