gio:menu-insert-item (menu pos item)

menu -- a g:menu object
pos -- an integer with the position at which to insert item
item -- a g:menu-item object to insert

Inserts a menu item into the menu. The "insertion" is actually done by copying all of the attribute and link values of item and using them to form a new menu item within the menu. As such, item itself is not really inserted, but rather, a menu item that is exactly the same as the one presently described by item.

This means that item is essentially useless after the insertion occurs. Any changes you make to it are ignored unless it is inserted again, at which point its updated values will be copied.

There are many convenience functions to take care of common cases. See the g:menu-insert, g:menu-insert-section and g:menu-insert-submenu functions as well as "prepend" and "append" variants of each of these functions.