The menu form field type provides a drop down list of the available menus from Joomla site. If the field has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected. The first option on the list is always '- Select Menu -' (which is a translatable string) and is given the value 0.
Example XML field definition:
<field name="mymenu" type="menu" default="mainmenu" label="Select a menu" description="" />
- type must be menu.
- name is the unique name of the field.
- label (translatable) is the descriptive title of the field.
- default is the default menu. This is the name of the menu shown in the Type column on the Menu Manager screen and not the menu ID number.
- description (translatable) is text that will be shown as a tooltip when the user moves the mouse over the drop-down box.