The new course editing UX uses submenus to group status options like availability (visible, hidden, stealth) and group mode (no groups, separate, visible).

This issue will implement all the generic classes to implement one level submenus inside the standard action_menu.

Example of the availability submenu:

Example of the group mode

Technical shaping

Currently, the action_menu class has a method "add" which accepts:

• action_menu_link: depending on some inner attribute the link will be rendered as a secondary or primary action item
• pix_icon: will be used a a primary action item
• Any other renderable: will be used a secondary item and rendered freely inside the menu.

A new class core\output\local\action_menu\subpanel will appear to render menu items with a subpanel. The class will be similar to a regular action_menu_link but accepting a renderable for the panel content.

When a subpanel is passed to "action_menu::add":

• Set the element as a secondary element
• To render the action menu item, the class will export a pre-rendered version to the panel to the template data. It will use a standard render like any other output component to render the submenu content.

This issue will also provide a fixture page to test the component.