Development:Modules

Activity modules

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
• 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:
  • widget_delete_course() - code to clean up anything that would be leftover after all instances are deleted
  • widget_process_options() - code to pre-process the form data from module settings
  • widget_reset_course_form() and widget_delete_userdata() - used to implement Reset course feature.
• 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_utf8/widget.php - (optional) Lastly, each module will have some language files that contain strings for that module.

IMPORTANT:

• 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

• Development:Blocks
• Development:Backup
• Tracker issue [https://tracker.moodle.org/browse/CONTRIB-52 CONTRIB-52 Improvements to make NEWMODULE really useful] - including download link for new module template supporting roles, formslib etc. (unfinished)
• http://download.moodle.org/plugins16/mod/NEWMODULE.zip - new module template for versions of Moodle prior to 1.7. Please follow the README instructions inside the zip.
• Development:NEWMODULE_Documentation

Using Moodle forum discussions:

• A new resource type: where do I put the language strings?
• New Module Template Code for Moodle 1.7
• LEGACY roles and capabilities