Extend Joomla Forms Using Plugins

Presentation “Extend Joomla Forms Using Plugins” - http://slideshare.net/yireoJisse Reitsma ([email protected]) - Twitter @yireo @jissereitsma #jwc14

Extend Joomla FormsUsing Plugins


My name is Jisse Reitsma

Developer

Owner of Yireo

Joomla! & Magento

Extensions & services

Tutorials & blogs

Sponsoring JWC2014


Plugins I wrote

Language Domains

Auto Login IP

Demo Site

Fancybox

HTTP Authenticatie

New Relic

Piwik

WebP

ScriptMerge

SEF Test

SSL Redirection

Static Content

Trademark

32+ MageBridge plugins

10+ SimpleLists plugins

8+ Dynamic404 plugins


Book release in November 2014

English

368 pages

Available through:

Yireo Shop (Europe)

Amazon (US & world wide)

#deadtreeformat (no ebook)


Extend Joomla Forms Using Plugins

Part I - Events & JForm

Part II - Code

Part III - Braindump

Presentation online: http://slideshare.net/yireo

Tweets: @yireo / @jissereitsma

Code: github.com/yireo/JoomlaPluginsBook


Part I:Events & JForm


Extensions

Component

Modules

Plugins

Libraries

Language files


Plugin groups

Authentication

Content

System

User

Editors

Editor Buttons

Search

Finder

CAPTCHA

Extension

Quick Icon


Content events

onContentPrepareForm

onContentAfterSave

onContentAfterDelete

onContentBeforeDisplay


JForm

Joomla core library for handling forms

XML form definition + PHP logic

Tasks

Form generation (HTML)

Validation

Filtering


MVC

Model

View

Controller


MVC workflow (simple)

User requests page

Controller calls view

View fetches data from model

View shows page


MVC workflow (form)

User requests form


View shows form

User submits form (POST)

Controller picks up on POST

Controller validates & filters form

Model stores form data

Controller redirects back to form or other page


MVC workflow (form)

User requests form


View shows form (JForm)

User submits form (POST)

Controller picks up on POST

Controller validates & filters form (JForm)

Model stores form data

Controller redirects back to form or other page


Part II:Code


Content events


onContentAfterSave

onContentAfterDelete



Goal

Add a custom field to backends article form

Store that fields value in a separate database table

Show that fields value in the same form again

Show that fields value in the frontend



Goal


Goal






Goal




onContentAfterSave






Content Plugin files

plugins/content/example/example.php

plugins/content/example/example.xml

plugins/content/exampe/form/default.xml

administrator/languages/en-GB/en-GB.plg_content_example.ini

administrator/languages/en-GB/en-GB.plg_content_example.sys.ini









Language files (1/2)

PLG_CONTENT_EXAMPLE="Content Example"PLG_CONTENT_EXAMPLE_DESC="An example Content Plugin"

PLG_CONTENT_EXAMPLE_FIELD_EXAMPLE_LABEL=”Test”PLG_CONTENT_EXAMPLE_FIELD_EXAMPLE_DESC=”New field”


Language files (2/2)

*.sys.ini = Always loaded

Add plugin title + description, but not much more

*.ini = Only loaded specifically

When editing a plugin in backend

When showing plugin in frontend ($autoLoadLanguage = true)

Add all language strings you need (backend + frontend)









XML manifest

<?xml version="1.0" encoding="utf8"?><extension version="3.0" type="plugin" group="content"> <name>PLG_CONTENT_EXAMPLE</name> <description>PLG_CONTENT_EXAMPLE_DESC</description> <version>0.0.1</version> <files> <filename plugin=”example”>example.php</filename> <folder>form</folder> </files> <languages> <language tag=”enGB”>enGB.plg_content_example.ini</language> <language tag=”enGB”>enGB.plg_content_example.sys.ini</language> </languages></extension>









XML form

<?xml version="1.0" encoding="utf8"?><form> <fields> <fieldset name="jmetadata"> <field name="example" type="text" label="PLG_CONTENT_EXAMPLE_FIELD_EXAMPLE_LABEL" description="PLG_CONTENT_EXAMPLE_FIELD_EXAMPLE_DESC" /> </fieldset> </fields></form>









Content Plugin - basic structure

<?phpdefined('_JEXEC') or die();

class plgContentExample extends JPlugin{}


Content Plugin - basic structure

<?phpdefined('_JEXEC') or die();

class plgContentExample extends JPlugin{ public function onContentPrepareForm($form, $data) {} public function onContentAfterSave($context, $item, $isNew) {} public function onContentBeforeDisplay($context, $item, $params, $page) {}}


Goal




onContentAfterSave







public function onContentPrepareForm($form, $data){ ... JForm::addFormPath(__DIR__.'/form'); // subfolder “form” $form>loadFile('default'); // file “form/default.xml” ... return true;}



public function onContentPrepareForm($form, $data){ if (!($form instanceof JForm)) { $this>_subject>setError('JERROR_NOT_A_FORM'); return false; }

$name = $form>getName(); if (!in_array($name, array('com_content.article'))) { return true; }

...



... if(!empty($data>id))

{

$data = $this>loadExample($data);

}

return true;}


loadExample

protected function loadExample($data){ $db = JFactory::getDbo(); $query = $db>getQuery(true); $query>select('*') >from($db>quoteName('#__example')) >where($db>quoteName('content_id') . ' = '.$data>id); $db>setQuery($query);

$exampleData = $db>loadAssoc(); $data>example = $exampleData['example']; return $data;}


Goal




onContentAfterSave






onContentAfterSave

public function onContentAfterSave( $context, $article, $isNew) { if (!in_array($context, array('com_content.article'))) { return true; }

...


onContentAfterSave

... $jinput = JFactory::getApplication()>input; $form = $jinput>post>get('jform', null, 'array'); if (is_array($form) && isset($form['example'])) { $example = $form['example']; } else { return true; } ...


onContentAfterSave

... $content_id = $article>id; $this>saveExample($content_id, $context, $example); return true;

}


saveExample

protected function saveExample($content_id, $context, $test){ $db = JFactory::getDbo();

$query = $db>getQuery(true); $query>select($db>quoteName('content_id')) >from($db>quoteName('#__example')) >where($db>quoteName('content_id').'='.$content_id);

$db>setQuery($query); $db>execute() $exists = (bool)$db>getNumRows(); ...


saveExample

... $data = new stdClass(); $data>content_id = $content_id; $data>context = $context; $data>example = $example; if($exists) { $result = $db>updateObject('#__example', $data, 'content_id'); } else { $result = $db>insertObject('#__example', $data); }

return true;}


Goal




onContentAfterSave







public function onContentBeforeDisplay( $context, &$row, &$params, $page = 0){ if(!empty($row>id)) { $row = $this>loadExample($row); }

if (!empty($row>example)) { $row>text .= '<p>EXAMPLE: '.$row>example.'<p>'; }}


Part 3:Braindump


Forms are everywhere

Article form

Category form

User profile form

Menu-Item form

Contact form


JForm manipulation

$form->load($xml)

$form->loadFile($file)

$form->bind($data)

$form->getField($name, $group, $value)

$form->removeField($field)

$form->setField($xml)


JForm output

$form->getInput($field, $group)

$form->getLabel($field, $group)

$form->getName($field, $group)

$form->getValue($field, $group)

$form->renderField($field, $group)

$form->getFieldset($fieldset)

$form->getFieldsets($group)


Showing new field values

4 times the same event

onContentPrepare

onContentAfterTitle


onContentAfterDisplay

Template override


Loading a language file - Joomla! 2.5

public function __construct(& $subject, $config){ parent::__construct($subject, $config); $this>loadLanguage();}


Loading a language file - Joomla! 3.x

protected $autoloadLanguage = true;


github.com/yireo/JoomlaPluginsBook/chapter05

https://github.com/yireo/JoomlaPluginsBook/tree/master/chapter05


@yireo

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Extend Joomla Forms Using Plugins