provides data to a popup menu controller implementation to
fill and update a popup menu dynamically.
A popup menu controller gets a ::com::sun::star::awt::XPopupMenu
from its parent menu implementation. The controller has to fill this popup
menu with a set of menu items and/or sub menus. The parent menu implementation
briefs the controller whenever the popup menu gets activated by a user.
briefs the popup menu controller to update the contents of the provided
popup menu to reflect the current state.
A controller should never update the popup menu structure on its
own to prevent performance problems. A better way would be that a controller
registers itself as status listener to for a command URL and immediately
deregister after that. Therefor status updates will not be send regularly
for a non visible popup menu.
