Activity modules

Revision as of 16:28, 8 March 2012 by Seth Battin (talk | contribs)

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Activity modules reside in the /mod directory. Each module is in a separate subdirectory and consists of the following mandatory elements (plus extra scripts unique to each module):

  • mod_form.php - a form to set up or update an instance of this module
  • version.php - defines some meta-info
  • pix/icon.gif - a 16x16 icon for the module
  • db/install.xml - defines the structure of db tables for all database types. Is used during module installation
  • db/upgrade.php - defines changes in the structure of db tables. Is used during module upgrade
  • db/access.php - defines module capabilities
  • index.php - a page to list all instances in a course
  • view.php - a page to view a particular instance
  • lib.php - any/all functions defined by the module should be in here. If the module name is called widget, then the required functions include:
  • widget_install() - will be called during the installation of the module
  • widget_add_instance() - code to add a new instance of widget
  • widget_update_instance() - code to update an existing instance
  • widget_delete_instance() - code to delete an instance
  • widget_user_outline() - given an instance, return a summary of a user's contribution
  • widget_user_complete() - given an instance, print details of a user's contribution
  • widget_get_view_actions() / widget_get_post_actions() - Used by the participation report (course/report/participation/index.php) to classify actions in the logs table.
  • Other functions available but not required are:
  • To avoid possible conflict, any module functions should be named starting with widget_ and any constants you define should start with WIDGET_
  • backuplib.php and restorelib.php (optional)
  • settings.php or settingstree.php - (optional) a definition of an admin settings page for this module. mod/assignment/settings.php is a good simple example. mod/quiz/settingstree.php is a more complex example.
  • defaults.php - lets you easily define default values for your configuration variables. It is included by upgrade_activity_modules in lib/adminlib.php. It should define an array $defaults. These values are then loaded into the config table. Alternatively, if you set $defaults['_use_config_plugins'] to true, the values are instead loaded into the config_plugins table, which is better practice. See mod/quiz/defaults.php for an example. (This apparently only works with moodle 2.x branch.)
  • lang/en/widget.php - (optional) Lastly, each module will have some language files that contain strings for that module.


  • When creating a new module, the new name of the module must not contain numbers or other special characters!
  • You need a data base table with the same name as your module. This table must have at least three fields:
    1. id
    2. course
    3. name
  • You should also make sure that your activity module provides appropriate support for groups and meta-courses.

See also

Using Moodle forum discussions: