Module assignments in Joomla
Steven Matz made his MLB debut for the Mets earlier today. I think the kid’s going to be all right.
A couple of weeks ago I made a Joomla component for managing menu-module relationships from a per-menu perspective rather than a per-module one. Since this required research on how Joomla records these relationships I figured it’d be worth sharing this information.
Joomla uses a table #__modules_menu with two columns, menuid and moduleid. When configuring the Menu Assignment section of a Joomla module there are four options to choose from in the “Module Assignment” dropdown:
- On all pages
- No pages
- Only on the pages selected
- On all pages except those selected
The rules for storing rows in the #__modules_menu table for each selection are as follows:
- For all pages, store one row with this module id and 0 as the menu id
- For no pages, do not store any row with this module id
- For only selected pages, store one row per menu id with this module id
- For on all pages except selected, store the negative menu id of each selection with this module id
For example, if I had three menu items 1, 2, and 3 and a module with an id of 10 and I choose “Only on the pages selected” with menu 1 selected, the table would look like this:
| moduleId | menuId |
|---|---|
| 10 | 1 |
If I choose “All except selected” with menus 2 and 3 selected, the table would look like this:
| moduleId | menuId |
|---|---|
| 10 | -2 |
| 10 | -3 |
Pretty simple, but considering I could not find this information in any official documentation I’m hoping I can save someone else a trip through the Joomla source code.