This is an introduction to plugin and module extension development for Joomla 3. It was presented at Sydney JUG in April 2013, and was accompanied with some live demos of a simple content plugin and simple module. If you want the source code from the live demos, feel free to get in touch with me.

1. Joomla Plugin & Module
Develpment
Tim Plummer
http://twitter.com/bfsurvey
Presented at Sydney JUG 09/04/2013

2. What is a plugin?

3. What is a module?

4. Tools you need
• Web Server & PHP & MySQL
(XAMPP)
• Text editor or IDE (Textpad /
Notepad++ or Eclipse / Netbeans)
• Web browser (Firefox with firebug)

5. Getting started with plugins
• Can be as simple as two files
– yourplugin.xml
– yourplugin.php
• Located in /plugins/plugintype/yourplugin
• Triggered by events

6. Installation XML (aka manifest)
• yourplugin.xml file located in your
plugin folder
• Used when installing your plugin –
tells Joomla all the files used, and
the type of plugin it is.
• Contains information about the
plugin, such as it’s name, author,
version number etc.
• Has all the parameters (aka options)

7. Entry point
• yourplugin.php file located in your plugin
folder
• This code is executed when the plugin runs,
and can call other files.
• Does all the hard work

8. Types of plugins
• Authentication • Quick Icon
• Captcha • Search
• Content • Smart Search (finder)
• Editors • User
• Editors-XTD • System
• Extension

9. Plugin Event Triggers
• Authentication • Content
– onUserAuthenticate – onContentAfterDelete
– onUserAuthorisationFail – onContentAfterDisplay
ure – onContentAfterSave
• Captcha – onContentAfterTitle
– onCheckAnswer – onContentBeforeDelete
– onDisplay – onContentBeforeDisplay
– onInit – onContentBeforeSave
– onContentChangeState
– onContentPrepare
– onContentPrepareData
– onContentPrepareForm
– onContentSearch
– onContentSearchAreas

10. Plugin Event Triggers…cont
• Editors • Extension
– onDisplay – onExtensionAfterInstall
– onGetContent – onExtensionAfterSave
– onGetInsertMethod – onExtensionAfterUninstall
– onInit
– onExtensionAfterUpdate
– onSave
– onExtensionBeforeInstall
– onSetContent
– onExtensionBeforeSave
• Editors-XTD
– onDisplay – onExtensionBeforeUninstall
– onExtensionBeforeUpdate

11. Plugin Event Triggers…cont
• Quick Icon • System
– onGetIcons – onAfterDispatch
• Search – onAfterInitialise
– onAfterRender
– onContentSearchAreas
– onAfterRoute
– onContentSearch
• User
• Smart Search – onUserAfterDelete
– onFinderAfterDelete – onUserAfterSave
– onFinderAfterSave – onUserBeforeDelete
– onFinderBeforeSave – onUserBeforeSave
– onFinderCategoryChangeState – onUserLogin
– onFinderChangeState – onUserLogout

12. plg_content_joomlarocks
• Hello World sucks, so instead tonight we are
going to create a plugin called
plg_content_joomlarocks
• This plugin will find all the “Joomla!” text in
articles and replace it with “Joomla Rocks” and
turn this into a link that goes to
www.joomla.org

13. Set Error Reporting to Maximum

14. Demo time…

15. Getting Started with modules
• Slightly more complex than plugins,
but still way simpler than
components.
• Can be as little as three files (but
usually 4+)
– mod_yourmodule.xml
– mod_yourmodule.php
– helper.php
– /tmpl/default.php

16. Types of modules
• Two types
– Frontend Module (aka site)
• /modules/yourmodule
– Backend Module (aka administrator)
• /administrator/modules/yourmodule

17. Installation XML (aka manifest)
• mod_yourmodule.xml file located in
your module folder
• Used when installing your module –
tells Joomla all the files used, and the
type of module it is.
• Contains information about the
module, such as it’s name, author,
version number etc.
• Has all the parameters (aka options)

18. Entry Point
• mod_yourmodule.php file located in your
module folder
• This code is executed when the plugin runs,
and can call other files.
• Is lazy and makes the helper and view do all
the work.

19. Helper
• helper.php file located in module folder
• Talks to the database and prepares data for
the view.

20. The View
• Located in /tmpl/default.php in the module
folder
• Presents the data to the user
• Doesn’t know where the data came from or
how it is stored and doesn’t care (as Sargent
Schultz would say, I know nothing!).

21. mod_random_article
• Tonight we are going to create an article
mod_random_article
• This will randomly select an article and show
the title with a link.

22. Demo time…

23. Now you are ready to start creating
your own plugins and modules

24. Questions?

25. Tim Plummer
@bfsurvey
tim@tamlyncreative.com.au