Joomla! Documentation - User contributions [en]

User:Veronika

2015-04-29T04:40:13Z

Veronika:

Hello I am Veronika Patel From Ahmedabad , Gujarat, India..I am study MCA at Ganpat University .Now I am Trainee at Tailored Solution Ahmedabad.

J3.x:Developing an MVC Component/Basic backend

2015-03-25T05:18:28Z

Veronika: /* Following Coding Standars*/

J3.x:Developing an MVC Component/Adding categories

2015-03-24T13:11:23Z

Veronika: /* Contributors */

{{:J3.1:Developing a MVC Component}}

{{review}}

This is a multiple-article series of tutorials on how to develop a Model-View-Contoller [[Component]] for Joomla! Version {{JVer|{{CurrentSTSVer|minor}}}}.

== Introduction ==
This tutorial is part of the [[J3.2:Developing a MVC Component | Developing a MVC Component for Joomla! 3.2]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.

The Joomla framework has implemented the use of categories for all components. Adding categorized ability to a component is fairly simple.

== Modifying the SQL ==
In order to manage categories, we have to change the SQL tables.

With your favorite editor, modify ''admin/sql/install.mysql.utf8.sql'' and put these lines:

<span id="admin/sql/install.mysql.utf8.sql">
''admin/sql/install.mysql.utf8.sql''
<source lang="sql" highlight="7">
DROP TABLE IF EXISTS `#__helloworld`;

CREATE TABLE `#__helloworld` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`greeting` VARCHAR(25) NOT NULL,
`published` tinyint(4) NOT NULL,
`catid` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`)
)
ENGINE =MyISAM
AUTO_INCREMENT =0
DEFAULT CHARSET =utf8;

INSERT INTO `#__helloworld` (`greeting`) VALUES
('Hello World!'),
('Good bye World!');

</source>
</span>

<span id="admin/sql/updates/mysql/0.0.12.sql">
''admin/sql/updates/mysql/0.0.12.sql''
<source lang="sql">
ALTER TABLE `#__helloworld` ADD `catid` int(11) NOT NULL DEFAULT '0';
</source>
</span>

== Modifying the form ==
A HelloWorld message can now belong to a category. We have to modify the editing form. In the ''admin/models/forms/helloworld.xml'' file, put these lines:

<span id="admin/models/forms/helloworld.xml">
''admin/models/forms/helloworld.xml''
<source lang="xml" highlight="21-32">
<?xml version="1.0" encoding="utf-8"?>
<form
addrulepath="/administrator/components/com_helloworld/models/rules"
>
<fieldset>
<field
name="id"
type="hidden"
/>
<field
name="greeting"
type="text"
label="COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_GREETING_DESC"
size="40"
class="inputbox validate-greeting"
validate="greeting"
required="true"
default=""
/>
<field
name="catid"
type="category"
extension="com_helloworld"
class="inputbox"
default=""
label="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC"
required="true"
>
<option value="0">JOPTION_SELECT_CATEGORY</option>
</field>
</fieldset>
</form>
</source>
</span>

Note that the category can be 0 (representing no category).

== Modifying the menu type ==
The HelloWorld menu type displays a drop down list of all messages. If the message is categorized, we have to add the category in this display.

In the ''admin/models/fields/helloworld.php'' file, put these lines:

<span id="admin/models/fields/helloworld.php">
''admin/models/fields/helloworld.php''
<source lang="php" highlight="38,40-42,51,52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

JFormHelper::loadFieldClass('list');

/**
* HelloWorld Form Field class for the HelloWorld component
*
* @since 0.0.1
*/
class JFormFieldHelloWorld extends JFormFieldList
{
/**
* The field type.
*
* @var string
*/
protected $type = 'HelloWorld';

/**
* Method to get a list of options for a list input.
*
* @return array An array of JHtml options.
*/
protected function getOptions()
{
$db = JFactory::getDBO();
$query = $db->getQuery(true);
$query->select('#__helloworld.id as id,greeting,#__categories.title as category,catid');
$query->from('#__helloworld');
$query->leftJoin('#__categories on catid=#__categories.id');
// Retrieve only published items
$query->where('#__helloworld.published = 1');
$db->setQuery((string) $query);
$messages = $db->loadObjectList();
$options = array();

if ($messages)
{
foreach ($messages as $message)
{
$options[] = JHtml::_('select.option', $message->id, $message->greeting .
($message->catid ? ' (' . $message->category . ')' : ''));
}
}

$options = array_merge(parent::getOptions(), $options);

return $options;
}
}

</source>
</span>

It will now display the category between parenthesis.
Note: We have added a where clause too to filter out unpublished items.

== Managing the submenu ==
The ''com_categories'' component allows to set the submenu using a helper file. With your favorite file manager and editor, put a ''admin/helpers/helloworld.php'' file containing these lines:

<span id="admin/helpers/helloworld.php">
''admin/helpers/helloworld.php''
<source lang="php">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorld component helper.
*
* @param string $submenu The name of the active view.
*
* @return void
*
* @since 1.6
*/
abstract class HelloWorldHelper
{
/**
* Configure the Linkbar.
*
* @return Bool
*/

public static function addSubmenu($submenu)
{
JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_MESSAGES'),
'index.php?option=com_helloworld',
$submenu == 'messages'
);

JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_CATEGORIES'),
'index.php?option=com_categories&view=categories&extension=com_helloworld',
$submenu == 'categories'
);

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-48-helloworld ' .
'{background-image: url(../media/com_helloworld/images/tux-48x48.png);}');
if ($submenu == 'categories')
{
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION_CATEGORIES'));
}
}
}

</source>
</span>
'''NOTE:''' You MUST use your component name (without com_) for the helper file name, or else your submenus won't show in category view.

To import the helper class, put these lines in the ''admin/helloworld.php'' file:

<span id="admin/helloworld.php">
''admin/helloworld.php''
<source lang="php" highlight="17-19">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-helloworld {background-image: url(../media/com_helloworld/images/tux-16x16.png);}');

// Require helper file
JLoader::register('HelloWorldHelper', JPATH_COMPONENT . '/helpers/helloworld.php');

// Get an instance of the controller prefixed by HelloWorld
$controller = JControllerLegacy::getInstance('HelloWorld');

// Perform the Request task
$input = JFactory::getApplication()->input;
$controller->execute($input->getCmd('task'));

// Redirect if set by the controller
$controller->redirect();

</source>
</span>

This function will be automatically called by the ''com_categories'' component. Note that it will
* change the submenu
* change some css properties (for displaying icons)
* change the browser title if the submenu is ''categories''
* change the title and add a ''preferences'' button

The ''.icon-48-helloworld'' css class is now set in the ''addSubmenu'' function.
We have now to call this function in the hellowords view:

<span id="admin/views/helloworlds/view.html.php">
''admin/views/helloworlds/view.html.php''
<source lang="php" highlight="50-52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorlds View
*
* @since 0.0.1
*/
class HelloWorldViewHelloWorlds extends JViewLegacy
{
/**
* Display the Hello World view
*
* @param string $tpl The name of the template file to parse; automatically searches through the template paths.
*
* @return void
*/

function display($tpl = null)
{

// Get application
$app = JFactory::getApplication();
$context = "helloworld.list.admin.helloworld";
// Get data from the model
$this->items = $this->get('Items');
$this->pagination = $this->get('Pagination');
$this->state = $this->get('State');
$this->filter_order = $app->getUserStateFromRequest($context.'filter_order', 'filter_order', 'greeting', 'cmd');
$this->filter_order_Dir = $app->getUserStateFromRequest($context.'filter_order_Dir', 'filter_order_Dir', 'asc', 'cmd');
$this->filterForm = $this->get('FilterForm');
$this->activeFilters = $this->get('ActiveFilters');

// Check for errors.
if (count($errors = $this->get('Errors')))
{
JError::raiseError(500, implode('<br />', $errors));

return false;
}

// Set the submenu
HelloWorldHelper::addSubmenu('helloworlds');

// Set the toolbar and number of found items
$this->addToolBar();

// Display the template
parent::display($tpl);

// Set the document
$this->setDocument();
}

/**
* Add the page title and toolbar.
*
* @return void
*
* @since 1.6
*/
protected function addToolBar()
{
$title = JText::_('COM_HELLOWORLD_MANAGER_HELLOWORLDS');

if ($this->pagination->total)
{
$title .= "<span style='font-size: 0.5em; vertical-align: middle;'>(" . $this->pagination->total . ")</span>";
}

JToolBarHelper::title($title, 'helloworld');
JToolBarHelper::addNew('helloworld.add');
JToolBarHelper::editList('helloworld.edit');
JToolBarHelper::deleteList('', 'helloworlds.delete');
}
/**
* Method to set up the document properties
*
* @return void
*/
protected function setDocument()
{
$document = JFactory::getDocument();
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION'));
}
}
</source>
</span>

== Adding some ACL ==
<span id="admin/access.xml">
''admin/access.xml''
<source lang="xml">
<?xml version="1.0" encoding="utf-8" ?>
<access component="com_helloworld">
<section name="component">
<action name="core.admin" title="JACTION_ADMIN" description="JACTION_ADMIN_COMPONENT_DESC" />
<action name="core.manage" title="JACTION_MANAGE" description="JACTION_MANAGE_COMPONENT_DESC" />
<action name="core.create" title="JACTION_CREATE" description="JACTION_CREATE_COMPONENT_DESC" />
<action name="core.delete" title="JACTION_DELETE" description="JACTION_DELETE_COMPONENT_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="JACTION_EDIT_COMPONENT_DESC" />
</section>
<section name="message">
<action name="core.delete" title="JACTION_DELETE" description="COM_HELLOWORLD_ACCESS_DELETE_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="COM_HELLOWORLD_ACCESS_EDIT_DESC" />
</section>
</access>
</source>
</span>

'''NOTE:''' If you don't add this file, buttons "New" "Edit" and ... don't show in category view . for more information read section Adding ACL on top of the page.

== Adding some translation strings ==
Some strings have to be translated. In the ''admin/language/en-GB/en-GB.com_helloworld.ini'' file, put these lines:

<span id="admin/language/en-GB/en-GB.com_helloworld.ini">
''admin/language/en-GB/en-GB.com_helloworld.ini''
<source lang="ini" highlight="7,17-19,34,35">
; Joomla! Project
; Copyright (C) 2005 - 2015 Open Source Matters. All rights reserved.
; License GNU General Public License version 2 or later; see LICENSE.txt, see LICENSE.php
; Note : All ini files need to be saved as UTF-8

COM_HELLOWORLD_ADMINISTRATION="HelloWorld - Administration"
COM_HELLOWORLD_ADMINISTRATION_CATEGORIES="HelloWorld - Categories"
COM_HELLOWORLD_NUM="#"
COM_HELLOWORLD_HELLOWORLDS_FILTER="Filters"
COM_HELLOWORLD_PUBLISHED="Published"
COM_HELLOWORLD_HELLOWORLDS_NAME="Name"
COM_HELLOWORLD_ID="Id"

COM_HELLOWORLD_HELLOWORLD_CREATING="HelloWorld - Creating"
COM_HELLOWORLD_HELLOWORLD_DETAILS="Details"
COM_HELLOWORLD_HELLOWORLD_EDITING="HelloWorld - Editing"
COM_HELLOWORLD_HELLOWORLD_ERROR_UNACCEPTABLE="Some values are unacceptable"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC="The category the messages belongs to"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL="Category"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_DESC="This message will be displayed"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_LABEL="Message"
COM_HELLOWORLD_HELLOWORLD_HEADING_GREETING="Greeting"
COM_HELLOWORLD_HELLOWORLD_HEADING_ID="Id"
COM_HELLOWORLD_MANAGER_HELLOWORLD_EDIT="HelloWorld manager: Edit Message"
COM_HELLOWORLD_MANAGER_HELLOWORLD_NEW="HelloWorld manager: New Message"
COM_HELLOWORLD_MANAGER_HELLOWORLDS="HelloWorld manager"
COM_HELLOWORLD_EDIT_HELLOWORLD="Edit message"
COM_HELLOWORLD_N_ITEMS_DELETED_1="One message deleted"
COM_HELLOWORLD_N_ITEMS_DELETED_MORE="%d messages deleted"
COM_HELLOWORLD_N_ITEMS_PUBLISHED="%d message(s) published"
COM_HELLOWORLD_N_ITEMS_UNPUBLISHED="%d message(s) unpublished"
COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL="Greeting"
COM_HELLOWORLD_HELLOWORLD_GREETING_DESC="Add Hello World Greeting"
COM_HELLOWORLD_SUBMENU_MESSAGES="Messages"
COM_HELLOWORLD_SUBMENU_CATEGORIES="Categories"

</source>
</span>

== Packaging the component ==

Content of your code directory
* ''[[#helloworld.xml|helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/helloworld.php|site/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/controller.php|site/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/views/helloworld/tmpl/default.xml|site/views/helloworld/tmpl/default.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/models/helloworld.php|site/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/en-GB/index.html]]''
* [[J3.x:Developing a MVC Component/Adding language management#site.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|site/language/en-GB/en-GB.com_helloworld.ini]]
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/helloworld.php|admin/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/controller.php|admin/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/access.xml|admin/access.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/helpers/helloworld.php|admin/helpers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/helpers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/install.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/uninstall.mysql.utf8.sql|admin/sql/uninstall.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/mysql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/sql/updates/mysql/0.0.1.sql|admin/sql/updates/mysql/0.0.1.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/updates/mysql/0.0.6.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/sql/updates/mysql/0.0.12.sql|admin/sql/updates/mysql/0.0.12.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/fields/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/models/fields/helloworld.php|admin/models/fields/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/models/helloworlds.php|admin/models/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/helloworlds.php|admin/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/forms/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/forms/helloworld.js|admin/models/forms/helloworld.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/forms/helloworld.xml|admin/models/forms/helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/rules/greeting.php|admin/models/rules/greeting.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/rules/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworld.php|admin/controllers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworlds.php|admin/controllers/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/controllers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/view.html.php|admin/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/tmpl/edit.php|admin/views/helloworld/tmpl/edit.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/views/helloworld/submitbutton.js|admin/views/helloworld/submitbutton.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/view.html.php|admin/views/helloworlds/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/tmpl/default.php|admin/views/helloworlds/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/tables/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/tables/helloworld.php|admin/tables/helloworld.php]]''
* ''[[#admin/language/index.html|admin/language/index.html]]''
* ''[[#admin/language/en-GB/index.html|admin/language/en-GB/index.html]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|admin/language/en-GB/en-GB.com_helloworld.ini]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.sys.ini|admin/language/en-GB/en-GB.com_helloworld.sys.ini]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/images/index.html]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-16x16.png]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-48x48.png]]''

Create a compressed file of this directory or directly download the [https://github.com/scionescire/Joomla-3.2-Hello-World-Component/archive/step-12-adding-categories.zip archive] and install it using the extension manager of Joomla. You can add a menu item of this component using the menu manager in the backend.

<span id="helloworld.xml">
''helloworld.xml''
<source lang="xml" highlight="13,66,77,78">
<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.2.0" method="upgrade">

<name>COM_HELLOWORLD</name>

<creationDate>February 2015</creationDate>
<author>John Doe</author>
<authorEmail>john.doe@example.org</authorEmail>
<authorUrl>http://www.example.org</authorUrl>
<copyright>Copyright Info</copyright>
<license>License Info</license>

<version>0.0.12</version>

<description>COM_HELLOWORLD_DESCRIPTION</description>

<install> 
<sql>
<file driver="mysql" charset="utf8">sql/install.mysql.utf8.sql</file>
</sql>
</install>
<uninstall> 
<sql>
<file driver="mysql" charset="utf8">sql/uninstall.mysql.utf8.sql</file>
</sql>
</uninstall>
<update> 
<schemas>
<schemapath type="mysql">sql/updates/mysql</schemapath>
</schemas>
</update>



<files folder="site">
<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<folder>views</folder>
<folder>models</folder>
</files>

<languages folder="site/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
</languages>

<media destination="com_helloworld" folder="media">
<filename>index.html</filename>
<folder>images</folder>
</media>

<administration>

<menu link='index.php?option=com_helloworld' img="../media/com_helloworld/images/tux-16x16.png">COM_HELLOWORLD_MENU</menu>


<files folder="admin">

<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<filename>access.xml</filename>

<folder>sql</folder>

<folder>tables</folder>

<folder>models</folder>

<folder>views</folder>

<folder>controllers</folder>

<folder>helpers</folder>
</files>
<languages folder="admin/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
<language tag="en-GB">en-GB/en-GB.com_helloworld.sys.ini</language>
</languages>
</administration>

</extension>
</source>
</span>
{{:J3.2:Developing a MVC Component/Navigate
|prev=Adding verifications 

|next=Adding configuration }}

== Contributors ==
*[[User:cdemko|Christophe Demko]]
*[[User:oaksu|Ozgur Aksu]]
*[[User:Anibal.sanchez|Anibal Sanchez]] // Just a fix
*[[User:Postema|Hans Postema]] // Just another fix
*[[User:Scionescire|Scionescire]]
*[[User:Veronika|Veronika Patel]]

[[Category:Joomla! 3.0]]
[[Category:Joomla! 3.1]]
[[Category:Joomla! 3.2]]
[[Category:Beginner Development]]
[[Category:Component Development]]

J3.x:Developing an MVC Component/Adding categories

2015-03-24T13:10:30Z

Veronika: /* Contributors */

{{:J3.1:Developing a MVC Component}}

{{review}}

This is a multiple-article series of tutorials on how to develop a Model-View-Contoller [[Component]] for Joomla! Version {{JVer|{{CurrentSTSVer|minor}}}}.

== Introduction ==
This tutorial is part of the [[J3.2:Developing a MVC Component | Developing a MVC Component for Joomla! 3.2]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.

The Joomla framework has implemented the use of categories for all components. Adding categorized ability to a component is fairly simple.

== Modifying the SQL ==
In order to manage categories, we have to change the SQL tables.

With your favorite editor, modify ''admin/sql/install.mysql.utf8.sql'' and put these lines:

<span id="admin/sql/install.mysql.utf8.sql">
''admin/sql/install.mysql.utf8.sql''
<source lang="sql" highlight="7">
DROP TABLE IF EXISTS `#__helloworld`;

CREATE TABLE `#__helloworld` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`greeting` VARCHAR(25) NOT NULL,
`published` tinyint(4) NOT NULL,
`catid` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`)
)
ENGINE =MyISAM
AUTO_INCREMENT =0
DEFAULT CHARSET =utf8;

INSERT INTO `#__helloworld` (`greeting`) VALUES
('Hello World!'),
('Good bye World!');

</source>
</span>

<span id="admin/sql/updates/mysql/0.0.12.sql">
''admin/sql/updates/mysql/0.0.12.sql''
<source lang="sql">
ALTER TABLE `#__helloworld` ADD `catid` int(11) NOT NULL DEFAULT '0';
</source>
</span>

== Modifying the form ==
A HelloWorld message can now belong to a category. We have to modify the editing form. In the ''admin/models/forms/helloworld.xml'' file, put these lines:

<span id="admin/models/forms/helloworld.xml">
''admin/models/forms/helloworld.xml''
<source lang="xml" highlight="21-32">
<?xml version="1.0" encoding="utf-8"?>
<form
addrulepath="/administrator/components/com_helloworld/models/rules"
>
<fieldset>
<field
name="id"
type="hidden"
/>
<field
name="greeting"
type="text"
label="COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_GREETING_DESC"
size="40"
class="inputbox validate-greeting"
validate="greeting"
required="true"
default=""
/>
<field
name="catid"
type="category"
extension="com_helloworld"
class="inputbox"
default=""
label="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC"
required="true"
>
<option value="0">JOPTION_SELECT_CATEGORY</option>
</field>
</fieldset>
</form>
</source>
</span>

Note that the category can be 0 (representing no category).

== Modifying the menu type ==
The HelloWorld menu type displays a drop down list of all messages. If the message is categorized, we have to add the category in this display.

In the ''admin/models/fields/helloworld.php'' file, put these lines:

<span id="admin/models/fields/helloworld.php">
''admin/models/fields/helloworld.php''
<source lang="php" highlight="38,40-42,51,52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

JFormHelper::loadFieldClass('list');

/**
* HelloWorld Form Field class for the HelloWorld component
*
* @since 0.0.1
*/
class JFormFieldHelloWorld extends JFormFieldList
{
/**
* The field type.
*
* @var string
*/
protected $type = 'HelloWorld';

/**
* Method to get a list of options for a list input.
*
* @return array An array of JHtml options.
*/
protected function getOptions()
{
$db = JFactory::getDBO();
$query = $db->getQuery(true);
$query->select('#__helloworld.id as id,greeting,#__categories.title as category,catid');
$query->from('#__helloworld');
$query->leftJoin('#__categories on catid=#__categories.id');
// Retrieve only published items
$query->where('#__helloworld.published = 1');
$db->setQuery((string) $query);
$messages = $db->loadObjectList();
$options = array();

if ($messages)
{
foreach ($messages as $message)
{
$options[] = JHtml::_('select.option', $message->id, $message->greeting .
($message->catid ? ' (' . $message->category . ')' : ''));
}
}

$options = array_merge(parent::getOptions(), $options);

return $options;
}
}

</source>
</span>

It will now display the category between parenthesis.
Note: We have added a where clause too to filter out unpublished items.

== Managing the submenu ==
The ''com_categories'' component allows to set the submenu using a helper file. With your favorite file manager and editor, put a ''admin/helpers/helloworld.php'' file containing these lines:

<span id="admin/helpers/helloworld.php">
''admin/helpers/helloworld.php''
<source lang="php">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorld component helper.
*
* @param string $submenu The name of the active view.
*
* @return void
*
* @since 1.6
*/
abstract class HelloWorldHelper
{
/**
* Configure the Linkbar.
*
* @return Bool
*/

public static function addSubmenu($submenu)
{
JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_MESSAGES'),
'index.php?option=com_helloworld',
$submenu == 'messages'
);

JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_CATEGORIES'),
'index.php?option=com_categories&view=categories&extension=com_helloworld',
$submenu == 'categories'
);

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-48-helloworld ' .
'{background-image: url(../media/com_helloworld/images/tux-48x48.png);}');
if ($submenu == 'categories')
{
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION_CATEGORIES'));
}
}
}

</source>
</span>
'''NOTE:''' You MUST use your component name (without com_) for the helper file name, or else your submenus won't show in category view.

To import the helper class, put these lines in the ''admin/helloworld.php'' file:

<span id="admin/helloworld.php">
''admin/helloworld.php''
<source lang="php" highlight="17-19">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-helloworld {background-image: url(../media/com_helloworld/images/tux-16x16.png);}');

// Require helper file
JLoader::register('HelloWorldHelper', JPATH_COMPONENT . '/helpers/helloworld.php');

// Get an instance of the controller prefixed by HelloWorld
$controller = JControllerLegacy::getInstance('HelloWorld');

// Perform the Request task
$input = JFactory::getApplication()->input;
$controller->execute($input->getCmd('task'));

// Redirect if set by the controller
$controller->redirect();

</source>
</span>

This function will be automatically called by the ''com_categories'' component. Note that it will
* change the submenu
* change some css properties (for displaying icons)
* change the browser title if the submenu is ''categories''
* change the title and add a ''preferences'' button

The ''.icon-48-helloworld'' css class is now set in the ''addSubmenu'' function.
We have now to call this function in the hellowords view:

<span id="admin/views/helloworlds/view.html.php">
''admin/views/helloworlds/view.html.php''
<source lang="php" highlight="50-52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorlds View
*
* @since 0.0.1
*/
class HelloWorldViewHelloWorlds extends JViewLegacy
{
/**
* Display the Hello World view
*
* @param string $tpl The name of the template file to parse; automatically searches through the template paths.
*
* @return void
*/

function display($tpl = null)
{

// Get application
$app = JFactory::getApplication();
$context = "helloworld.list.admin.helloworld";
// Get data from the model
$this->items = $this->get('Items');
$this->pagination = $this->get('Pagination');
$this->state = $this->get('State');
$this->filter_order = $app->getUserStateFromRequest($context.'filter_order', 'filter_order', 'greeting', 'cmd');
$this->filter_order_Dir = $app->getUserStateFromRequest($context.'filter_order_Dir', 'filter_order_Dir', 'asc', 'cmd');
$this->filterForm = $this->get('FilterForm');
$this->activeFilters = $this->get('ActiveFilters');

// Check for errors.
if (count($errors = $this->get('Errors')))
{
JError::raiseError(500, implode('<br />', $errors));

return false;
}

// Set the submenu
HelloWorldHelper::addSubmenu('helloworlds');

// Set the toolbar and number of found items
$this->addToolBar();

// Display the template
parent::display($tpl);

// Set the document
$this->setDocument();
}

/**
* Add the page title and toolbar.
*
* @return void
*
* @since 1.6
*/
protected function addToolBar()
{
$title = JText::_('COM_HELLOWORLD_MANAGER_HELLOWORLDS');

if ($this->pagination->total)
{
$title .= "<span style='font-size: 0.5em; vertical-align: middle;'>(" . $this->pagination->total . ")</span>";
}

JToolBarHelper::title($title, 'helloworld');
JToolBarHelper::addNew('helloworld.add');
JToolBarHelper::editList('helloworld.edit');
JToolBarHelper::deleteList('', 'helloworlds.delete');
}
/**
* Method to set up the document properties
*
* @return void
*/
protected function setDocument()
{
$document = JFactory::getDocument();
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION'));
}
}
</source>
</span>

== Adding some ACL ==
<span id="admin/access.xml">
''admin/access.xml''
<source lang="xml">
<?xml version="1.0" encoding="utf-8" ?>
<access component="com_helloworld">
<section name="component">
<action name="core.admin" title="JACTION_ADMIN" description="JACTION_ADMIN_COMPONENT_DESC" />
<action name="core.manage" title="JACTION_MANAGE" description="JACTION_MANAGE_COMPONENT_DESC" />
<action name="core.create" title="JACTION_CREATE" description="JACTION_CREATE_COMPONENT_DESC" />
<action name="core.delete" title="JACTION_DELETE" description="JACTION_DELETE_COMPONENT_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="JACTION_EDIT_COMPONENT_DESC" />
</section>
<section name="message">
<action name="core.delete" title="JACTION_DELETE" description="COM_HELLOWORLD_ACCESS_DELETE_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="COM_HELLOWORLD_ACCESS_EDIT_DESC" />
</section>
</access>
</source>
</span>

'''NOTE:''' If you don't add this file, buttons "New" "Edit" and ... don't show in category view . for more information read section Adding ACL on top of the page.

== Adding some translation strings ==
Some strings have to be translated. In the ''admin/language/en-GB/en-GB.com_helloworld.ini'' file, put these lines:

<span id="admin/language/en-GB/en-GB.com_helloworld.ini">
''admin/language/en-GB/en-GB.com_helloworld.ini''
<source lang="ini" highlight="7,17-19,34,35">
; Joomla! Project
; Copyright (C) 2005 - 2015 Open Source Matters. All rights reserved.
; License GNU General Public License version 2 or later; see LICENSE.txt, see LICENSE.php
; Note : All ini files need to be saved as UTF-8

COM_HELLOWORLD_ADMINISTRATION="HelloWorld - Administration"
COM_HELLOWORLD_ADMINISTRATION_CATEGORIES="HelloWorld - Categories"
COM_HELLOWORLD_NUM="#"
COM_HELLOWORLD_HELLOWORLDS_FILTER="Filters"
COM_HELLOWORLD_PUBLISHED="Published"
COM_HELLOWORLD_HELLOWORLDS_NAME="Name"
COM_HELLOWORLD_ID="Id"

COM_HELLOWORLD_HELLOWORLD_CREATING="HelloWorld - Creating"
COM_HELLOWORLD_HELLOWORLD_DETAILS="Details"
COM_HELLOWORLD_HELLOWORLD_EDITING="HelloWorld - Editing"
COM_HELLOWORLD_HELLOWORLD_ERROR_UNACCEPTABLE="Some values are unacceptable"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC="The category the messages belongs to"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL="Category"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_DESC="This message will be displayed"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_LABEL="Message"
COM_HELLOWORLD_HELLOWORLD_HEADING_GREETING="Greeting"
COM_HELLOWORLD_HELLOWORLD_HEADING_ID="Id"
COM_HELLOWORLD_MANAGER_HELLOWORLD_EDIT="HelloWorld manager: Edit Message"
COM_HELLOWORLD_MANAGER_HELLOWORLD_NEW="HelloWorld manager: New Message"
COM_HELLOWORLD_MANAGER_HELLOWORLDS="HelloWorld manager"
COM_HELLOWORLD_EDIT_HELLOWORLD="Edit message"
COM_HELLOWORLD_N_ITEMS_DELETED_1="One message deleted"
COM_HELLOWORLD_N_ITEMS_DELETED_MORE="%d messages deleted"
COM_HELLOWORLD_N_ITEMS_PUBLISHED="%d message(s) published"
COM_HELLOWORLD_N_ITEMS_UNPUBLISHED="%d message(s) unpublished"
COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL="Greeting"
COM_HELLOWORLD_HELLOWORLD_GREETING_DESC="Add Hello World Greeting"
COM_HELLOWORLD_SUBMENU_MESSAGES="Messages"
COM_HELLOWORLD_SUBMENU_CATEGORIES="Categories"

</source>
</span>

== Packaging the component ==

Content of your code directory
* ''[[#helloworld.xml|helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/helloworld.php|site/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/controller.php|site/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/views/helloworld/tmpl/default.xml|site/views/helloworld/tmpl/default.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/models/helloworld.php|site/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/en-GB/index.html]]''
* [[J3.x:Developing a MVC Component/Adding language management#site.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|site/language/en-GB/en-GB.com_helloworld.ini]]
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/helloworld.php|admin/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/controller.php|admin/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/access.xml|admin/access.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/helpers/helloworld.php|admin/helpers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/helpers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/install.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/uninstall.mysql.utf8.sql|admin/sql/uninstall.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/mysql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/sql/updates/mysql/0.0.1.sql|admin/sql/updates/mysql/0.0.1.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/updates/mysql/0.0.6.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/sql/updates/mysql/0.0.12.sql|admin/sql/updates/mysql/0.0.12.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/fields/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/models/fields/helloworld.php|admin/models/fields/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/models/helloworlds.php|admin/models/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/helloworlds.php|admin/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/forms/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/forms/helloworld.js|admin/models/forms/helloworld.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/forms/helloworld.xml|admin/models/forms/helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/rules/greeting.php|admin/models/rules/greeting.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/rules/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworld.php|admin/controllers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworlds.php|admin/controllers/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/controllers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/view.html.php|admin/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/tmpl/edit.php|admin/views/helloworld/tmpl/edit.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/views/helloworld/submitbutton.js|admin/views/helloworld/submitbutton.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/view.html.php|admin/views/helloworlds/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/tmpl/default.php|admin/views/helloworlds/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/tables/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/tables/helloworld.php|admin/tables/helloworld.php]]''
* ''[[#admin/language/index.html|admin/language/index.html]]''
* ''[[#admin/language/en-GB/index.html|admin/language/en-GB/index.html]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|admin/language/en-GB/en-GB.com_helloworld.ini]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.sys.ini|admin/language/en-GB/en-GB.com_helloworld.sys.ini]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/images/index.html]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-16x16.png]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-48x48.png]]''

Create a compressed file of this directory or directly download the [https://github.com/scionescire/Joomla-3.2-Hello-World-Component/archive/step-12-adding-categories.zip archive] and install it using the extension manager of Joomla. You can add a menu item of this component using the menu manager in the backend.

<span id="helloworld.xml">
''helloworld.xml''
<source lang="xml" highlight="13,66,77,78">
<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.2.0" method="upgrade">

<name>COM_HELLOWORLD</name>

<creationDate>February 2015</creationDate>
<author>John Doe</author>
<authorEmail>john.doe@example.org</authorEmail>
<authorUrl>http://www.example.org</authorUrl>
<copyright>Copyright Info</copyright>
<license>License Info</license>

<version>0.0.12</version>

<description>COM_HELLOWORLD_DESCRIPTION</description>

<install> 
<sql>
<file driver="mysql" charset="utf8">sql/install.mysql.utf8.sql</file>
</sql>
</install>
<uninstall> 
<sql>
<file driver="mysql" charset="utf8">sql/uninstall.mysql.utf8.sql</file>
</sql>
</uninstall>
<update> 
<schemas>
<schemapath type="mysql">sql/updates/mysql</schemapath>
</schemas>
</update>



<files folder="site">
<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<folder>views</folder>
<folder>models</folder>
</files>

<languages folder="site/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
</languages>

<media destination="com_helloworld" folder="media">
<filename>index.html</filename>
<folder>images</folder>
</media>

<administration>

<menu link='index.php?option=com_helloworld' img="../media/com_helloworld/images/tux-16x16.png">COM_HELLOWORLD_MENU</menu>


<files folder="admin">

<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<filename>access.xml</filename>

<folder>sql</folder>

<folder>tables</folder>

<folder>models</folder>

<folder>views</folder>

<folder>controllers</folder>

<folder>helpers</folder>
</files>
<languages folder="admin/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
<language tag="en-GB">en-GB/en-GB.com_helloworld.sys.ini</language>
</languages>
</administration>

</extension>
</source>
</span>
{{:J3.2:Developing a MVC Component/Navigate
|prev=Adding verifications 

|next=Adding configuration }}

== Contributors ==
*[[User:cdemko|Christophe Demko]]
*[[User:oaksu|Ozgur Aksu]]
*[[User:Anibal.sanchez|Anibal Sanchez]] // Just a fix
*[[User:Postema|Hans Postema]] // Just another fix
*[[User:Scionescire|Scionescire]]
*[[User:Veronika]]

[[Category:Joomla! 3.0]]
[[Category:Joomla! 3.1]]
[[Category:Joomla! 3.2]]
[[Category:Beginner Development]]
[[Category:Component Development]]

J3.x:Developing an MVC Component/Adding categories

2015-03-24T13:09:39Z

Veronika: /* Contributors */

{{:J3.1:Developing a MVC Component}}

{{review}}

This is a multiple-article series of tutorials on how to develop a Model-View-Contoller [[Component]] for Joomla! Version {{JVer|{{CurrentSTSVer|minor}}}}.

== Introduction ==
This tutorial is part of the [[J3.2:Developing a MVC Component | Developing a MVC Component for Joomla! 3.2]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.

The Joomla framework has implemented the use of categories for all components. Adding categorized ability to a component is fairly simple.

== Modifying the SQL ==
In order to manage categories, we have to change the SQL tables.

With your favorite editor, modify ''admin/sql/install.mysql.utf8.sql'' and put these lines:

<span id="admin/sql/install.mysql.utf8.sql">
''admin/sql/install.mysql.utf8.sql''
<source lang="sql" highlight="7">
DROP TABLE IF EXISTS `#__helloworld`;

CREATE TABLE `#__helloworld` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`greeting` VARCHAR(25) NOT NULL,
`published` tinyint(4) NOT NULL,
`catid` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`)
)
ENGINE =MyISAM
AUTO_INCREMENT =0
DEFAULT CHARSET =utf8;

INSERT INTO `#__helloworld` (`greeting`) VALUES
('Hello World!'),
('Good bye World!');

</source>
</span>

<span id="admin/sql/updates/mysql/0.0.12.sql">
''admin/sql/updates/mysql/0.0.12.sql''
<source lang="sql">
ALTER TABLE `#__helloworld` ADD `catid` int(11) NOT NULL DEFAULT '0';
</source>
</span>

== Modifying the form ==
A HelloWorld message can now belong to a category. We have to modify the editing form. In the ''admin/models/forms/helloworld.xml'' file, put these lines:

<span id="admin/models/forms/helloworld.xml">
''admin/models/forms/helloworld.xml''
<source lang="xml" highlight="21-32">
<?xml version="1.0" encoding="utf-8"?>
<form
addrulepath="/administrator/components/com_helloworld/models/rules"
>
<fieldset>
<field
name="id"
type="hidden"
/>
<field
name="greeting"
type="text"
label="COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_GREETING_DESC"
size="40"
class="inputbox validate-greeting"
validate="greeting"
required="true"
default=""
/>
<field
name="catid"
type="category"
extension="com_helloworld"
class="inputbox"
default=""
label="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC"
required="true"
>
<option value="0">JOPTION_SELECT_CATEGORY</option>
</field>
</fieldset>
</form>
</source>
</span>

Note that the category can be 0 (representing no category).

== Modifying the menu type ==
The HelloWorld menu type displays a drop down list of all messages. If the message is categorized, we have to add the category in this display.

In the ''admin/models/fields/helloworld.php'' file, put these lines:

<span id="admin/models/fields/helloworld.php">
''admin/models/fields/helloworld.php''
<source lang="php" highlight="38,40-42,51,52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

JFormHelper::loadFieldClass('list');

/**
* HelloWorld Form Field class for the HelloWorld component
*
* @since 0.0.1
*/
class JFormFieldHelloWorld extends JFormFieldList
{
/**
* The field type.
*
* @var string
*/
protected $type = 'HelloWorld';

/**
* Method to get a list of options for a list input.
*
* @return array An array of JHtml options.
*/
protected function getOptions()
{
$db = JFactory::getDBO();
$query = $db->getQuery(true);
$query->select('#__helloworld.id as id,greeting,#__categories.title as category,catid');
$query->from('#__helloworld');
$query->leftJoin('#__categories on catid=#__categories.id');
// Retrieve only published items
$query->where('#__helloworld.published = 1');
$db->setQuery((string) $query);
$messages = $db->loadObjectList();
$options = array();

if ($messages)
{
foreach ($messages as $message)
{
$options[] = JHtml::_('select.option', $message->id, $message->greeting .
($message->catid ? ' (' . $message->category . ')' : ''));
}
}

$options = array_merge(parent::getOptions(), $options);

return $options;
}
}

</source>
</span>

It will now display the category between parenthesis.
Note: We have added a where clause too to filter out unpublished items.

== Managing the submenu ==
The ''com_categories'' component allows to set the submenu using a helper file. With your favorite file manager and editor, put a ''admin/helpers/helloworld.php'' file containing these lines:

<span id="admin/helpers/helloworld.php">
''admin/helpers/helloworld.php''
<source lang="php">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorld component helper.
*
* @param string $submenu The name of the active view.
*
* @return void
*
* @since 1.6
*/
abstract class HelloWorldHelper
{
/**
* Configure the Linkbar.
*
* @return Bool
*/

public static function addSubmenu($submenu)
{
JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_MESSAGES'),
'index.php?option=com_helloworld',
$submenu == 'messages'
);

JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_CATEGORIES'),
'index.php?option=com_categories&view=categories&extension=com_helloworld',
$submenu == 'categories'
);

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-48-helloworld ' .
'{background-image: url(../media/com_helloworld/images/tux-48x48.png);}');
if ($submenu == 'categories')
{
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION_CATEGORIES'));
}
}
}

</source>
</span>
'''NOTE:''' You MUST use your component name (without com_) for the helper file name, or else your submenus won't show in category view.

To import the helper class, put these lines in the ''admin/helloworld.php'' file:

<span id="admin/helloworld.php">
''admin/helloworld.php''
<source lang="php" highlight="17-19">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-helloworld {background-image: url(../media/com_helloworld/images/tux-16x16.png);}');

// Require helper file
JLoader::register('HelloWorldHelper', JPATH_COMPONENT . '/helpers/helloworld.php');

// Get an instance of the controller prefixed by HelloWorld
$controller = JControllerLegacy::getInstance('HelloWorld');

// Perform the Request task
$input = JFactory::getApplication()->input;
$controller->execute($input->getCmd('task'));

// Redirect if set by the controller
$controller->redirect();

</source>
</span>

This function will be automatically called by the ''com_categories'' component. Note that it will
* change the submenu
* change some css properties (for displaying icons)
* change the browser title if the submenu is ''categories''
* change the title and add a ''preferences'' button

The ''.icon-48-helloworld'' css class is now set in the ''addSubmenu'' function.
We have now to call this function in the hellowords view:

<span id="admin/views/helloworlds/view.html.php">
''admin/views/helloworlds/view.html.php''
<source lang="php" highlight="50-52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorlds View
*
* @since 0.0.1
*/
class HelloWorldViewHelloWorlds extends JViewLegacy
{
/**
* Display the Hello World view
*
* @param string $tpl The name of the template file to parse; automatically searches through the template paths.
*
* @return void
*/

function display($tpl = null)
{

// Get application
$app = JFactory::getApplication();
$context = "helloworld.list.admin.helloworld";
// Get data from the model
$this->items = $this->get('Items');
$this->pagination = $this->get('Pagination');
$this->state = $this->get('State');
$this->filter_order = $app->getUserStateFromRequest($context.'filter_order', 'filter_order', 'greeting', 'cmd');
$this->filter_order_Dir = $app->getUserStateFromRequest($context.'filter_order_Dir', 'filter_order_Dir', 'asc', 'cmd');
$this->filterForm = $this->get('FilterForm');
$this->activeFilters = $this->get('ActiveFilters');

// Check for errors.
if (count($errors = $this->get('Errors')))
{
JError::raiseError(500, implode('<br />', $errors));

return false;
}

// Set the submenu
HelloWorldHelper::addSubmenu('helloworlds');

// Set the toolbar and number of found items
$this->addToolBar();

// Display the template
parent::display($tpl);

// Set the document
$this->setDocument();
}

/**
* Add the page title and toolbar.
*
* @return void
*
* @since 1.6
*/
protected function addToolBar()
{
$title = JText::_('COM_HELLOWORLD_MANAGER_HELLOWORLDS');

if ($this->pagination->total)
{
$title .= "<span style='font-size: 0.5em; vertical-align: middle;'>(" . $this->pagination->total . ")</span>";
}

JToolBarHelper::title($title, 'helloworld');
JToolBarHelper::addNew('helloworld.add');
JToolBarHelper::editList('helloworld.edit');
JToolBarHelper::deleteList('', 'helloworlds.delete');
}
/**
* Method to set up the document properties
*
* @return void
*/
protected function setDocument()
{
$document = JFactory::getDocument();
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION'));
}
}
</source>
</span>

== Adding some ACL ==
<span id="admin/access.xml">
''admin/access.xml''
<source lang="xml">
<?xml version="1.0" encoding="utf-8" ?>
<access component="com_helloworld">
<section name="component">
<action name="core.admin" title="JACTION_ADMIN" description="JACTION_ADMIN_COMPONENT_DESC" />
<action name="core.manage" title="JACTION_MANAGE" description="JACTION_MANAGE_COMPONENT_DESC" />
<action name="core.create" title="JACTION_CREATE" description="JACTION_CREATE_COMPONENT_DESC" />
<action name="core.delete" title="JACTION_DELETE" description="JACTION_DELETE_COMPONENT_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="JACTION_EDIT_COMPONENT_DESC" />
</section>
<section name="message">
<action name="core.delete" title="JACTION_DELETE" description="COM_HELLOWORLD_ACCESS_DELETE_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="COM_HELLOWORLD_ACCESS_EDIT_DESC" />
</section>
</access>
</source>
</span>

'''NOTE:''' If you don't add this file, buttons "New" "Edit" and ... don't show in category view . for more information read section Adding ACL on top of the page.

== Adding some translation strings ==
Some strings have to be translated. In the ''admin/language/en-GB/en-GB.com_helloworld.ini'' file, put these lines:

<span id="admin/language/en-GB/en-GB.com_helloworld.ini">
''admin/language/en-GB/en-GB.com_helloworld.ini''
<source lang="ini" highlight="7,17-19,34,35">
; Joomla! Project
; Copyright (C) 2005 - 2015 Open Source Matters. All rights reserved.
; License GNU General Public License version 2 or later; see LICENSE.txt, see LICENSE.php
; Note : All ini files need to be saved as UTF-8

COM_HELLOWORLD_ADMINISTRATION="HelloWorld - Administration"
COM_HELLOWORLD_ADMINISTRATION_CATEGORIES="HelloWorld - Categories"
COM_HELLOWORLD_NUM="#"
COM_HELLOWORLD_HELLOWORLDS_FILTER="Filters"
COM_HELLOWORLD_PUBLISHED="Published"
COM_HELLOWORLD_HELLOWORLDS_NAME="Name"
COM_HELLOWORLD_ID="Id"

COM_HELLOWORLD_HELLOWORLD_CREATING="HelloWorld - Creating"
COM_HELLOWORLD_HELLOWORLD_DETAILS="Details"
COM_HELLOWORLD_HELLOWORLD_EDITING="HelloWorld - Editing"
COM_HELLOWORLD_HELLOWORLD_ERROR_UNACCEPTABLE="Some values are unacceptable"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC="The category the messages belongs to"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL="Category"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_DESC="This message will be displayed"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_LABEL="Message"
COM_HELLOWORLD_HELLOWORLD_HEADING_GREETING="Greeting"
COM_HELLOWORLD_HELLOWORLD_HEADING_ID="Id"
COM_HELLOWORLD_MANAGER_HELLOWORLD_EDIT="HelloWorld manager: Edit Message"
COM_HELLOWORLD_MANAGER_HELLOWORLD_NEW="HelloWorld manager: New Message"
COM_HELLOWORLD_MANAGER_HELLOWORLDS="HelloWorld manager"
COM_HELLOWORLD_EDIT_HELLOWORLD="Edit message"
COM_HELLOWORLD_N_ITEMS_DELETED_1="One message deleted"
COM_HELLOWORLD_N_ITEMS_DELETED_MORE="%d messages deleted"
COM_HELLOWORLD_N_ITEMS_PUBLISHED="%d message(s) published"
COM_HELLOWORLD_N_ITEMS_UNPUBLISHED="%d message(s) unpublished"
COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL="Greeting"
COM_HELLOWORLD_HELLOWORLD_GREETING_DESC="Add Hello World Greeting"
COM_HELLOWORLD_SUBMENU_MESSAGES="Messages"
COM_HELLOWORLD_SUBMENU_CATEGORIES="Categories"

</source>
</span>

== Packaging the component ==

Content of your code directory
* ''[[#helloworld.xml|helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/helloworld.php|site/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/controller.php|site/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/views/helloworld/tmpl/default.xml|site/views/helloworld/tmpl/default.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/models/helloworld.php|site/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/en-GB/index.html]]''
* [[J3.x:Developing a MVC Component/Adding language management#site.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|site/language/en-GB/en-GB.com_helloworld.ini]]
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/helloworld.php|admin/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/controller.php|admin/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/access.xml|admin/access.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/helpers/helloworld.php|admin/helpers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/helpers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/install.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/uninstall.mysql.utf8.sql|admin/sql/uninstall.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/mysql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/sql/updates/mysql/0.0.1.sql|admin/sql/updates/mysql/0.0.1.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/updates/mysql/0.0.6.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/sql/updates/mysql/0.0.12.sql|admin/sql/updates/mysql/0.0.12.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/fields/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/models/fields/helloworld.php|admin/models/fields/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/models/helloworlds.php|admin/models/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/helloworlds.php|admin/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/forms/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/forms/helloworld.js|admin/models/forms/helloworld.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/forms/helloworld.xml|admin/models/forms/helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/rules/greeting.php|admin/models/rules/greeting.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/rules/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworld.php|admin/controllers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworlds.php|admin/controllers/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/controllers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/view.html.php|admin/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/tmpl/edit.php|admin/views/helloworld/tmpl/edit.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/views/helloworld/submitbutton.js|admin/views/helloworld/submitbutton.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/view.html.php|admin/views/helloworlds/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/tmpl/default.php|admin/views/helloworlds/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/tables/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/tables/helloworld.php|admin/tables/helloworld.php]]''
* ''[[#admin/language/index.html|admin/language/index.html]]''
* ''[[#admin/language/en-GB/index.html|admin/language/en-GB/index.html]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|admin/language/en-GB/en-GB.com_helloworld.ini]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.sys.ini|admin/language/en-GB/en-GB.com_helloworld.sys.ini]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/images/index.html]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-16x16.png]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-48x48.png]]''

Create a compressed file of this directory or directly download the [https://github.com/scionescire/Joomla-3.2-Hello-World-Component/archive/step-12-adding-categories.zip archive] and install it using the extension manager of Joomla. You can add a menu item of this component using the menu manager in the backend.

<span id="helloworld.xml">
''helloworld.xml''
<source lang="xml" highlight="13,66,77,78">
<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.2.0" method="upgrade">

<name>COM_HELLOWORLD</name>

<creationDate>February 2015</creationDate>
<author>John Doe</author>
<authorEmail>john.doe@example.org</authorEmail>
<authorUrl>http://www.example.org</authorUrl>
<copyright>Copyright Info</copyright>
<license>License Info</license>

<version>0.0.12</version>

<description>COM_HELLOWORLD_DESCRIPTION</description>

<install> 
<sql>
<file driver="mysql" charset="utf8">sql/install.mysql.utf8.sql</file>
</sql>
</install>
<uninstall> 
<sql>
<file driver="mysql" charset="utf8">sql/uninstall.mysql.utf8.sql</file>
</sql>
</uninstall>
<update> 
<schemas>
<schemapath type="mysql">sql/updates/mysql</schemapath>
</schemas>
</update>



<files folder="site">
<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<folder>views</folder>
<folder>models</folder>
</files>

<languages folder="site/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
</languages>

<media destination="com_helloworld" folder="media">
<filename>index.html</filename>
<folder>images</folder>
</media>

<administration>

<menu link='index.php?option=com_helloworld' img="../media/com_helloworld/images/tux-16x16.png">COM_HELLOWORLD_MENU</menu>


<files folder="admin">

<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<filename>access.xml</filename>

<folder>sql</folder>

<folder>tables</folder>

<folder>models</folder>

<folder>views</folder>

<folder>controllers</folder>

<folder>helpers</folder>
</files>
<languages folder="admin/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
<language tag="en-GB">en-GB/en-GB.com_helloworld.sys.ini</language>
</languages>
</administration>

</extension>
</source>
</span>
{{:J3.2:Developing a MVC Component/Navigate
|prev=Adding verifications 

|next=Adding configuration }}

== Contributors ==
*[[User:cdemko|Christophe Demko]]
*[[User:oaksu|Ozgur Aksu]]
*[[User:Anibal.sanchez|Anibal Sanchez]] // Just a fix
*[[User:Postema|Hans Postema]] // Just another fix
*[[User:Scionescire|Scionescire]]
*[[User:Veronika|Patel]]

[[Category:Joomla! 3.0]]
[[Category:Joomla! 3.1]]
[[Category:Joomla! 3.2]]
[[Category:Beginner Development]]
[[Category:Component Development]]

J3.x:Developing an MVC Component/Adding categories

2015-03-24T13:08:43Z

Veronika: /*following coding stander */

{{:J3.1:Developing a MVC Component}}

{{review}}

This is a multiple-article series of tutorials on how to develop a Model-View-Contoller [[Component]] for Joomla! Version {{JVer|{{CurrentSTSVer|minor}}}}.

== Introduction ==
This tutorial is part of the [[J3.2:Developing a MVC Component | Developing a MVC Component for Joomla! 3.2]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.

The Joomla framework has implemented the use of categories for all components. Adding categorized ability to a component is fairly simple.

== Modifying the SQL ==
In order to manage categories, we have to change the SQL tables.

With your favorite editor, modify ''admin/sql/install.mysql.utf8.sql'' and put these lines:

<span id="admin/sql/install.mysql.utf8.sql">
''admin/sql/install.mysql.utf8.sql''
<source lang="sql" highlight="7">
DROP TABLE IF EXISTS `#__helloworld`;

CREATE TABLE `#__helloworld` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`greeting` VARCHAR(25) NOT NULL,
`published` tinyint(4) NOT NULL,
`catid` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`)
)
ENGINE =MyISAM
AUTO_INCREMENT =0
DEFAULT CHARSET =utf8;

INSERT INTO `#__helloworld` (`greeting`) VALUES
('Hello World!'),
('Good bye World!');

</source>
</span>

<span id="admin/sql/updates/mysql/0.0.12.sql">
''admin/sql/updates/mysql/0.0.12.sql''
<source lang="sql">
ALTER TABLE `#__helloworld` ADD `catid` int(11) NOT NULL DEFAULT '0';
</source>
</span>

== Modifying the form ==
A HelloWorld message can now belong to a category. We have to modify the editing form. In the ''admin/models/forms/helloworld.xml'' file, put these lines:

<span id="admin/models/forms/helloworld.xml">
''admin/models/forms/helloworld.xml''
<source lang="xml" highlight="21-32">
<?xml version="1.0" encoding="utf-8"?>
<form
addrulepath="/administrator/components/com_helloworld/models/rules"
>
<fieldset>
<field
name="id"
type="hidden"
/>
<field
name="greeting"
type="text"
label="COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_GREETING_DESC"
size="40"
class="inputbox validate-greeting"
validate="greeting"
required="true"
default=""
/>
<field
name="catid"
type="category"
extension="com_helloworld"
class="inputbox"
default=""
label="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL"
description="COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC"
required="true"
>
<option value="0">JOPTION_SELECT_CATEGORY</option>
</field>
</fieldset>
</form>
</source>
</span>

Note that the category can be 0 (representing no category).

== Modifying the menu type ==
The HelloWorld menu type displays a drop down list of all messages. If the message is categorized, we have to add the category in this display.

In the ''admin/models/fields/helloworld.php'' file, put these lines:

<span id="admin/models/fields/helloworld.php">
''admin/models/fields/helloworld.php''
<source lang="php" highlight="38,40-42,51,52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

JFormHelper::loadFieldClass('list');

/**
* HelloWorld Form Field class for the HelloWorld component
*
* @since 0.0.1
*/
class JFormFieldHelloWorld extends JFormFieldList
{
/**
* The field type.
*
* @var string
*/
protected $type = 'HelloWorld';

/**
* Method to get a list of options for a list input.
*
* @return array An array of JHtml options.
*/
protected function getOptions()
{
$db = JFactory::getDBO();
$query = $db->getQuery(true);
$query->select('#__helloworld.id as id,greeting,#__categories.title as category,catid');
$query->from('#__helloworld');
$query->leftJoin('#__categories on catid=#__categories.id');
// Retrieve only published items
$query->where('#__helloworld.published = 1');
$db->setQuery((string) $query);
$messages = $db->loadObjectList();
$options = array();

if ($messages)
{
foreach ($messages as $message)
{
$options[] = JHtml::_('select.option', $message->id, $message->greeting .
($message->catid ? ' (' . $message->category . ')' : ''));
}
}

$options = array_merge(parent::getOptions(), $options);

return $options;
}
}

</source>
</span>

It will now display the category between parenthesis.
Note: We have added a where clause too to filter out unpublished items.

== Managing the submenu ==
The ''com_categories'' component allows to set the submenu using a helper file. With your favorite file manager and editor, put a ''admin/helpers/helloworld.php'' file containing these lines:

<span id="admin/helpers/helloworld.php">
''admin/helpers/helloworld.php''
<source lang="php">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorld component helper.
*
* @param string $submenu The name of the active view.
*
* @return void
*
* @since 1.6
*/
abstract class HelloWorldHelper
{
/**
* Configure the Linkbar.
*
* @return Bool
*/

public static function addSubmenu($submenu)
{
JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_MESSAGES'),
'index.php?option=com_helloworld',
$submenu == 'messages'
);

JSubMenuHelper::addEntry(
JText::_('COM_HELLOWORLD_SUBMENU_CATEGORIES'),
'index.php?option=com_categories&view=categories&extension=com_helloworld',
$submenu == 'categories'
);

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-48-helloworld ' .
'{background-image: url(../media/com_helloworld/images/tux-48x48.png);}');
if ($submenu == 'categories')
{
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION_CATEGORIES'));
}
}
}

</source>
</span>
'''NOTE:''' You MUST use your component name (without com_) for the helper file name, or else your submenus won't show in category view.

To import the helper class, put these lines in the ''admin/helloworld.php'' file:

<span id="admin/helloworld.php">
''admin/helloworld.php''
<source lang="php" highlight="17-19">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

// Set some global property
$document = JFactory::getDocument();
$document->addStyleDeclaration('.icon-helloworld {background-image: url(../media/com_helloworld/images/tux-16x16.png);}');

// Require helper file
JLoader::register('HelloWorldHelper', JPATH_COMPONENT . '/helpers/helloworld.php');

// Get an instance of the controller prefixed by HelloWorld
$controller = JControllerLegacy::getInstance('HelloWorld');

// Perform the Request task
$input = JFactory::getApplication()->input;
$controller->execute($input->getCmd('task'));

// Redirect if set by the controller
$controller->redirect();

</source>
</span>

This function will be automatically called by the ''com_categories'' component. Note that it will
* change the submenu
* change some css properties (for displaying icons)
* change the browser title if the submenu is ''categories''
* change the title and add a ''preferences'' button

The ''.icon-48-helloworld'' css class is now set in the ''addSubmenu'' function.
We have now to call this function in the hellowords view:

<span id="admin/views/helloworlds/view.html.php">
''admin/views/helloworlds/view.html.php''
<source lang="php" highlight="50-52">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorlds View
*
* @since 0.0.1
*/
class HelloWorldViewHelloWorlds extends JViewLegacy
{
/**
* Display the Hello World view
*
* @param string $tpl The name of the template file to parse; automatically searches through the template paths.
*
* @return void
*/

function display($tpl = null)
{

// Get application
$app = JFactory::getApplication();
$context = "helloworld.list.admin.helloworld";
// Get data from the model
$this->items = $this->get('Items');
$this->pagination = $this->get('Pagination');
$this->state = $this->get('State');
$this->filter_order = $app->getUserStateFromRequest($context.'filter_order', 'filter_order', 'greeting', 'cmd');
$this->filter_order_Dir = $app->getUserStateFromRequest($context.'filter_order_Dir', 'filter_order_Dir', 'asc', 'cmd');
$this->filterForm = $this->get('FilterForm');
$this->activeFilters = $this->get('ActiveFilters');

// Check for errors.
if (count($errors = $this->get('Errors')))
{
JError::raiseError(500, implode('<br />', $errors));

return false;
}

// Set the submenu
HelloWorldHelper::addSubmenu('helloworlds');

// Set the toolbar and number of found items
$this->addToolBar();

// Display the template
parent::display($tpl);

// Set the document
$this->setDocument();
}

/**
* Add the page title and toolbar.
*
* @return void
*
* @since 1.6
*/
protected function addToolBar()
{
$title = JText::_('COM_HELLOWORLD_MANAGER_HELLOWORLDS');

if ($this->pagination->total)
{
$title .= "<span style='font-size: 0.5em; vertical-align: middle;'>(" . $this->pagination->total . ")</span>";
}

JToolBarHelper::title($title, 'helloworld');
JToolBarHelper::addNew('helloworld.add');
JToolBarHelper::editList('helloworld.edit');
JToolBarHelper::deleteList('', 'helloworlds.delete');
}
/**
* Method to set up the document properties
*
* @return void
*/
protected function setDocument()
{
$document = JFactory::getDocument();
$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION'));
}
}
</source>
</span>

== Adding some ACL ==
<span id="admin/access.xml">
''admin/access.xml''
<source lang="xml">
<?xml version="1.0" encoding="utf-8" ?>
<access component="com_helloworld">
<section name="component">
<action name="core.admin" title="JACTION_ADMIN" description="JACTION_ADMIN_COMPONENT_DESC" />
<action name="core.manage" title="JACTION_MANAGE" description="JACTION_MANAGE_COMPONENT_DESC" />
<action name="core.create" title="JACTION_CREATE" description="JACTION_CREATE_COMPONENT_DESC" />
<action name="core.delete" title="JACTION_DELETE" description="JACTION_DELETE_COMPONENT_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="JACTION_EDIT_COMPONENT_DESC" />
</section>
<section name="message">
<action name="core.delete" title="JACTION_DELETE" description="COM_HELLOWORLD_ACCESS_DELETE_DESC" />
<action name="core.edit" title="JACTION_EDIT" description="COM_HELLOWORLD_ACCESS_EDIT_DESC" />
</section>
</access>
</source>
</span>

'''NOTE:''' If you don't add this file, buttons "New" "Edit" and ... don't show in category view . for more information read section Adding ACL on top of the page.

== Adding some translation strings ==
Some strings have to be translated. In the ''admin/language/en-GB/en-GB.com_helloworld.ini'' file, put these lines:

<span id="admin/language/en-GB/en-GB.com_helloworld.ini">
''admin/language/en-GB/en-GB.com_helloworld.ini''
<source lang="ini" highlight="7,17-19,34,35">
; Joomla! Project
; Copyright (C) 2005 - 2015 Open Source Matters. All rights reserved.
; License GNU General Public License version 2 or later; see LICENSE.txt, see LICENSE.php
; Note : All ini files need to be saved as UTF-8

COM_HELLOWORLD_ADMINISTRATION="HelloWorld - Administration"
COM_HELLOWORLD_ADMINISTRATION_CATEGORIES="HelloWorld - Categories"
COM_HELLOWORLD_NUM="#"
COM_HELLOWORLD_HELLOWORLDS_FILTER="Filters"
COM_HELLOWORLD_PUBLISHED="Published"
COM_HELLOWORLD_HELLOWORLDS_NAME="Name"
COM_HELLOWORLD_ID="Id"

COM_HELLOWORLD_HELLOWORLD_CREATING="HelloWorld - Creating"
COM_HELLOWORLD_HELLOWORLD_DETAILS="Details"
COM_HELLOWORLD_HELLOWORLD_EDITING="HelloWorld - Editing"
COM_HELLOWORLD_HELLOWORLD_ERROR_UNACCEPTABLE="Some values are unacceptable"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_DESC="The category the messages belongs to"
COM_HELLOWORLD_HELLOWORLD_FIELD_CATID_LABEL="Category"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_DESC="This message will be displayed"
COM_HELLOWORLD_HELLOWORLD_FIELD_GREETING_LABEL="Message"
COM_HELLOWORLD_HELLOWORLD_HEADING_GREETING="Greeting"
COM_HELLOWORLD_HELLOWORLD_HEADING_ID="Id"
COM_HELLOWORLD_MANAGER_HELLOWORLD_EDIT="HelloWorld manager: Edit Message"
COM_HELLOWORLD_MANAGER_HELLOWORLD_NEW="HelloWorld manager: New Message"
COM_HELLOWORLD_MANAGER_HELLOWORLDS="HelloWorld manager"
COM_HELLOWORLD_EDIT_HELLOWORLD="Edit message"
COM_HELLOWORLD_N_ITEMS_DELETED_1="One message deleted"
COM_HELLOWORLD_N_ITEMS_DELETED_MORE="%d messages deleted"
COM_HELLOWORLD_N_ITEMS_PUBLISHED="%d message(s) published"
COM_HELLOWORLD_N_ITEMS_UNPUBLISHED="%d message(s) unpublished"
COM_HELLOWORLD_HELLOWORLD_GREETING_LABEL="Greeting"
COM_HELLOWORLD_HELLOWORLD_GREETING_DESC="Add Hello World Greeting"
COM_HELLOWORLD_SUBMENU_MESSAGES="Messages"
COM_HELLOWORLD_SUBMENU_CATEGORIES="Categories"

</source>
</span>

== Packaging the component ==

Content of your code directory
* ''[[#helloworld.xml|helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/helloworld.php|site/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/controller.php|site/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/views/helloworld/tmpl/default.xml|site/views/helloworld/tmpl/default.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#site/models/helloworld.php|site/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/language/en-GB/index.html]]''
* [[J3.x:Developing a MVC Component/Adding language management#site.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|site/language/en-GB/en-GB.com_helloworld.ini]]
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/helloworld.php|admin/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/controller.php|admin/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/access.xml|admin/access.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/helpers/helloworld.php|admin/helpers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/helpers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/install.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/uninstall.mysql.utf8.sql|admin/sql/uninstall.mysql.utf8.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/mysql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/sql/updates/mysql/0.0.1.sql|admin/sql/updates/mysql/0.0.1.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/sql/install.mysql.utf8.sql|admin/sql/updates/mysql/0.0.6.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_categories#admin/sql/updates/mysql/0.0.12.sql|admin/sql/updates/mysql/0.0.12.sql]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/fields/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/models/fields/helloworld.php|admin/models/fields/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/models/helloworlds.php|admin/models/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/helloworlds.php|admin/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/forms/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/forms/helloworld.js|admin/models/forms/helloworld.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/models/forms/helloworld.xml|admin/models/forms/helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/models/rules/greeting.php|admin/models/rules/greeting.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/models/rules/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworld.php|admin/controllers/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/controllers/helloworlds.php|admin/controllers/helloworlds.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/controllers/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/view.html.php|admin/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_backend_actions#admin/views/helloworld/tmpl/edit.php|admin/views/helloworld/tmpl/edit.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_verifications#admin/views/helloworld/submitbutton.js|admin/views/helloworld/submitbutton.js]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/view.html.php|admin/views/helloworlds/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/views/helloworlds/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Basic_backend#admin/views/helloworlds/tmpl/default.php|admin/views/helloworlds/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/tables/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Using_the_database#admin/tables/helloworld.php|admin/tables/helloworld.php]]''
* ''[[#admin/language/index.html|admin/language/index.html]]''
* ''[[#admin/language/en-GB/index.html|admin/language/en-GB/index.html]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.ini|admin/language/en-GB/en-GB.com_helloworld.ini]]''
* ''[[J3.x:Developing a MVC Component/Adding language management#admin.2Flanguage.2Fen-GB.2Fen-GB.com_helloworld.sys.ini|admin/language/en-GB/en-GB.com_helloworld.sys.ini]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|media/images/index.html]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-16x16.png]]''
* ''[[J3.x:Developing_a_MVC_Component/Adding_decorations_to_the_backend#Adding_some_icons|media/images/tux-48x48.png]]''

Create a compressed file of this directory or directly download the [https://github.com/scionescire/Joomla-3.2-Hello-World-Component/archive/step-12-adding-categories.zip archive] and install it using the extension manager of Joomla. You can add a menu item of this component using the menu manager in the backend.

<span id="helloworld.xml">
''helloworld.xml''
<source lang="xml" highlight="13,66,77,78">
<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.2.0" method="upgrade">

<name>COM_HELLOWORLD</name>

<creationDate>February 2015</creationDate>
<author>John Doe</author>
<authorEmail>john.doe@example.org</authorEmail>
<authorUrl>http://www.example.org</authorUrl>
<copyright>Copyright Info</copyright>
<license>License Info</license>

<version>0.0.12</version>

<description>COM_HELLOWORLD_DESCRIPTION</description>

<install> 
<sql>
<file driver="mysql" charset="utf8">sql/install.mysql.utf8.sql</file>
</sql>
</install>
<uninstall> 
<sql>
<file driver="mysql" charset="utf8">sql/uninstall.mysql.utf8.sql</file>
</sql>
</uninstall>
<update> 
<schemas>
<schemapath type="mysql">sql/updates/mysql</schemapath>
</schemas>
</update>



<files folder="site">
<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<folder>views</folder>
<folder>models</folder>
</files>

<languages folder="site/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
</languages>

<media destination="com_helloworld" folder="media">
<filename>index.html</filename>
<folder>images</folder>
</media>

<administration>

<menu link='index.php?option=com_helloworld' img="../media/com_helloworld/images/tux-16x16.png">COM_HELLOWORLD_MENU</menu>


<files folder="admin">

<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<filename>access.xml</filename>

<folder>sql</folder>

<folder>tables</folder>

<folder>models</folder>

<folder>views</folder>

<folder>controllers</folder>

<folder>helpers</folder>
</files>
<languages folder="admin/language">
<language tag="en-GB">en-GB/en-GB.com_helloworld.ini</language>
<language tag="en-GB">en-GB/en-GB.com_helloworld.sys.ini</language>
</languages>
</administration>

</extension>
</source>
</span>
{{:J3.2:Developing a MVC Component/Navigate
|prev=Adding verifications 

|next=Adding configuration }}

== Contributors ==
*[[User:cdemko|Christophe Demko]]
*[[User:oaksu|Ozgur Aksu]]
*[[User:Anibal.sanchez|Anibal Sanchez]] // Just a fix
*[[User:Postema|Hans Postema]] // Just another fix
*[[User:Scionescire|Scionescire]]

[[Category:Joomla! 3.0]]
[[Category:Joomla! 3.1]]
[[Category:Joomla! 3.2]]
[[Category:Beginner Development]]
[[Category:Component Development]]

J3.x:Developing an MVC Component/Adding a model to the site part

2015-03-17T12:39:05Z

Veronika: /* Adding a model */

{{:J3.1:Developing a MVC Component}}

== Introduction ==
This tutorial is part of the [[J3.2:Developing a MVC Component | Developing a MVC Component for Joomla! 3.2]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.

== Adding a model ==
In the Joomla framework, models are responsible for managing the data. The first function that has to be written for a model is a ''get'' function. It returns data to the caller. In our case, the caller will be the ''HelloWorldViewHelloWorld'' view. By default, the model named ''HelloWorldModelHelloWorld'' residing in ''site/models/helloworld.php'' is the main model associated to this view.

So let's have a quick look at the naming conventions with an example, since the naming convention are the actual magic, that make everything work:

The class ''HelloWorldView'''HelloWorld''''' resides in ''site/views/'''helloworld'''/view.html.php'' and will make use of the class ''HelloWorldModel'''HelloWorld''''' in the file ''site/models/'''helloworld'''.php''

So let's just assume we want to use an imaginary view ''fluffy'', you would have to have:

The class ''HelloWorldView'''Fluffy''''' which resides in ''site/views/'''fluffy'''/view.html.php''. The view will make use of ''HelloWorldModel'''Fluffy''''' in the file ''site/models/'''fluffy'''.php''. Note: the actual screen of the view: ''site/views/'''fluffy'''/tmpl/default.php'' is required as well to make this example work.

Breaking any of these bold conventions will lead to errors or a blank page.

So back to the actual implementation of the single classes:

With your favorite file manager and editor put a ''site/models/helloworld.php'' file containing:

<span id="site/models/helloworld.php">
''site/models/helloworld.php''
<source lang="php">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HelloWorld Model
*
* @since 0.0.1
*/
class HelloWorldModelHelloWorld extends JModelItem
{
/**
* @var string message
*/
protected $message;

/**
* Get the message
*
* @return string The message to be displayed to the user
*/
public function getMsg()
{
if (!isset($this->message))
{
$this->message = 'Hello World!';
}

return $this->message;
}
}
</source>
</span>

The ''HelloWorldViewHelloWorld'' class asks the model for data using the ''get'' method of the ''JViewLegacy'' class:

<span id="site/views/helloworld/view.html.php">
''site/views/helloworld/view.html.php''
<source lang="php" highlight="30">
<?php
/**
* @package Joomla.Administrator
* @subpackage com_helloworld
*
* @copyright Copyright (C) 2005 - 2015 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
* HTML View class for the HelloWorld Component
*
* @since 0.0.1
*/
class HelloWorldViewHelloWorld extends JViewLegacy
{
/**
* Display the Hello World view
*
* @param string $tpl The name of the template file to parse; automatically searches through the template paths.
*
* @return void
*/
function display($tpl = null)
{
// Assign data to the view
$this->msg = $this->get('Msg');

// Check for errors.
if (count($errors = $this->get('Errors')))
{
JLog::add(implode('<br />', $errors), JLog::WARNING, 'jerror');

return false;
}

// Display the view
parent::display($tpl);
}
}

</source>
</span>

Note: $this->get() is a member of JViewLegacy::get which is a proxy to get* methods of the default model where * is populated with the value of the first parameter passed to get()

Also modify your ''helloworld.xml'' file to indicate use of models and the new version:

<span id="helloworld.xml">
''helloworld.xml''
<source lang="xml" highlight="13,32">
<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.2.0" method="upgrade">

<name>Hello World!</name>

<creationDate>January 2014</creationDate>
<author>John Doe</author>
<authorEmail>john.doe@example.org</authorEmail>
<authorUrl>http://www.example.org</authorUrl>
<copyright>Copyright Info</copyright>
<license>License Info</license>

<version>0.0.4</version>

<description>Description of the Hello World component ...</description>

<update> 
<schemas>
<schemapath type="mysql">sql/updates/mysql</schemapath>
</schemas>
</update>



<files folder="site">
<filename>index.html</filename>
<filename>helloworld.php</filename>
<filename>controller.php</filename>
<folder>views</folder>
<folder>models</folder>
</files>

<administration>

<menu link='index.php?option=com_helloworld'>Hello World!</menu>


<files folder="admin">

<filename>index.html</filename>
<filename>helloworld.php</filename>

<folder>sql</folder>
</files>
</administration>

</extension>
</source>
</span>

== Packaging the component ==

Content of your code directory
* ''[[#helloworld.xml|helloworld.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/helloworld.php|site/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/controller.php|site/controller.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/tmpl/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_menu_type_to_the_site_part#site/views/helloworld/tmpl/default.xml|site/views/helloworld/tmpl/default.xml]]''
* ''[[J3.2:Developing_a_MVC_Component/Adding_a_view_to_the_site_part#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/models/index.html]]''
* ''[[#site/models/helloworld.php|site/models/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/helloworld.php|admin/helloworld.php]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/mysql/index.html]]''
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/sql/updates/mysql/0.0.1.sql|admin/sql/updates/mysql/0.0.1.sql]]''
Create a compressed file of this directory or directly download the [https://github.com/scionescire/Joomla-3.2-Hello-World-Component/archive/step-4-adding-a-site-model.zip archive] and install it using the extension manager of Joomla. You can add a menu item of this component using the menu manager in the backend.

{{notice|Please create a pull request or issue at https://github.com/joomla/Joomla-3.2-Hello-World-Component for any code descprepancies or if editing any of the source code on this page.}}

{{:J3.2:Developing a MVC Component/Navigate
|prev=Adding a menu type to the site part 
|next=Adding a variable request in the menu type }}

== Contributors ==
*[[User:cdemko|Christophe Demko]]
*[[User:oaksu|Ozgur Aksu]]
*[[User:Jossnaz|Lukas Meier]]
*[[User:betweenbrain|Matt Thomas]]
*[[User:Scionescire|Scionescire]]

[[Category:Joomla! 3.0]]
[[Category:Joomla! 3.1]]
[[Category:Joomla! 3.2]]
[[Category:Beginner Development]]
[[Category:Component Development]]

User:Veronika

2015-03-17T12:31:20Z

Veronika: Created page with "Hello I am Veronika Patel From Ahmedabad, Gujarat, India"

Hello I am Veronika Patel From Ahmedabad, Gujarat, India