I would like to be able to create a navigation menu in WordPress in which the top-level nav items are not pages, but rather menu headings, which expand the sub menu when clicked.
The default WP menu behavior is that all menu items are links to content (pages, posts, etc), and that sub-items are viewed upon hover.
I’m looking for a way to make it work more like the menu behavior built into Twitter Bootstrap (and for the same usability reason).
I’m looking for a solution that either already exists as a plugin, or which I can build into a plugin, so that anyone can create a new menu like this in the WordPress menu editor.
checkout this tutorial :
https://digwp.com/2011/11/html-formatting-custom-menus/
If you dont want any custom html structure than you can simply add the classed to menu and for top level menu create a custom link with # as href.