J3.x

Difference between revisions of "Developing an MVC Component/Adding a view to the site part"

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m (high lights file name than beginner easily to understand)
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== Introduction ==
 
== Introduction ==
This tutorial is part of the [[Developing a Model-View-Controller (MVC) Component for Joomla!2.5]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.
+
This tutorial is part of the [[J3.2:Developing_a_MVC_Component|Developing a Model-View-Controller (MVC) Component for Joomla! 3.x]] tutorial. You are encouraged to read the previous parts of the tutorial before reading this.
  
 
In the Joomla!3.x framework, third party component authors divide their code into three main parts:
 
In the Joomla!3.x framework, third party component authors divide their code into three main parts:
Line 11: Line 11:
  
 
== Setting the controller ==
 
== Setting the controller ==
In the core code of Joomla, there is a class able to manage controllers: ''[http://api.joomla.org/Joomla-Platform/Application/JController.html JController]''. This class has to be extended to be used in our component. In the file ''site/helloworld.php'' (entry point of our ''Hello World'' component), put these lines
+
In the core code of Joomla, there is a class able to manage controllers: ''[https://api.joomla.org/cms-3/classes/JControllerLegacy.html JControllerLegacy]''. This class has to be extended to be used in our component. In the file ''yoursite/components/com_helloworld/helloworld.php'' (entry point of our ''Hello World'' component), put these lines:
  
 
{{vanchor|site/helloworld.php}}
 
{{vanchor|site/helloworld.php}}
 
<source lang="php">
 
<source lang="php">
 
<?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
 
// No direct access to this file
 
defined('_JEXEC') or die('Restricted access');
 
defined('_JEXEC') or die('Restricted access');
 
// import joomla controller library
 
jimport('joomla.application.component.controller');
 
  
 
// Get an instance of the controller prefixed by HelloWorld
 
// Get an instance of the controller prefixed by HelloWorld
$controller = JController::getInstance('HelloWorld');
+
$controller = JControllerLegacy::getInstance('HelloWorld');
  
 
// Perform the Request task
 
// Perform the Request task
Line 31: Line 36:
 
// Redirect if set by the controller
 
// Redirect if set by the controller
 
$controller->redirect();
 
$controller->redirect();
 +
 
</source>
 
</source>
  
The ''[http://api.joomla.org/Joomla-Platform/Application/JController.html#getInstance getInstance]'' static method of the ''JController'' class will create a controller. In the code above, it will instantiate a controller object of a class named ''HelloWorldController''. Joomla will look for the declaration of that class in an aptly named file called ''controller.php'' (it's a default behavior).
+
The ''[https://api.joomla.org/cms-3/classes/JControllerLegacy.html#method_getInstance getInstance]'' static method of the ''JControllerLegacy'' class will create a controller. In the code above, it will instantiate a controller object of a class named ''HelloWorldController''. Joomla will look for the declaration of that class in an aptly named file called ''yoursite/components/com_helloworld/controller.php'' (it's a default behavior).
  
Now, ''controller.php'' needs to be created and ''HelloWorldController'' needs to be declared and defined. So with your favorite file manager and editor, create a ''site/controller.php'' file containing
+
Now, ''controller.php'' needs to be created and ''HelloWorldController'' needs to be declared and defined. So with your favorite file manager and editor, create a ''yoursite/components/com_helloworld/controller.php'' file containing
  
 
{{vanchor|site/controller.php}}
 
{{vanchor|site/controller.php}}
 
<source lang="php">
 
<source lang="php">
 
<?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
 
// No direct access to this file
 
defined('_JEXEC') or die('Restricted access');
 
defined('_JEXEC') or die('Restricted access');
 
// import Joomla controller library
 
jimport('joomla.application.component.controller');
 
 
 
/**
 
/**
 
  * Hello World Component Controller
 
  * Hello World Component Controller
 +
*
 +
* @since  0.0.1
 
  */
 
  */
class HelloWorldController extends JController
+
class HelloWorldController extends JControllerLegacy
 
{
 
{
 
}
 
}
 
</source>
 
</source>
  
When no task is given in the request variables, the default task will be executed. It's the ''display'' task by default. The ''JController'' class has such a task. In our example, it will display a view named ''HelloWorld''.
+
When no task is given in the request variables, the default task will be executed. It's the ''display'' task by default. The ''JControllerLegacy'' class has such a task. In our example, it will display a view named ''HelloWorld''.
 +
 
 +
So with ''task'' simply a public function display() of ''JControllerLegacy'' is refered to.
 +
 
 +
 
 +
{{tip|Just a side note for completion, you could call another function aside from ''display()'' by using an URL like this one:
 +
 
 +
<pre>http://localhost/index.php?option=com_helloworld&task=insert</pre>
 +
 
 +
This would try to call a function ''insert()'' of our controller (which we would actually have to implement in ''HelloWorldController'' ).}}
  
 
== Setting the view ==
 
== Setting the view ==
  
When JController wants to display a view, it will look for certain files in the ''component/com_[component_name]/views/[name of view]/'' folder.  
+
When JControllerLegacy wants to display a view, it will look for certain files in the ''yoursite/components/com_[component_name]/views/[name of view]/'' folder.  
  
The name of the folder of the default view is the name of the component itself. In our case the path is ''component/com_helloworld/views/helloworld/''.
+
The name of the folder of the default view is the name of the component itself. In our case the path is ''yoursite/components/com_helloworld/views/helloworld/''.
  
 
The file that will contain the code of the view is called ''view.[view_mode].php''. The default view mode, and probably the only view a component might need is the ''html'' mode. So this give us our file name which is ''view.html.php''.
 
The file that will contain the code of the view is called ''view.[view_mode].php''. The default view mode, and probably the only view a component might need is the ''html'' mode. So this give us our file name which is ''view.html.php''.
  
With your favorite file manager and editor, create a file ''site/views/helloworld/view.html.php'' able to display the default view and containing
+
With your favorite file manager and editor, '''create a file ''yoursite/components/com_helloworld/views/helloworld/view.html.php''''' able to display the default view and containing:
  
<span id="site/views/helloworld/view.html.php">
 
''site/views/helloworld/view.html.php''
 
 
<source lang="php">
 
<source lang="php">
 
<?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
 
// No direct access to this file
 
defined('_JEXEC') or die('Restricted access');
 
defined('_JEXEC') or die('Restricted access');
 
// import Joomla view library
 
jimport('joomla.application.component.view');
 
  
 
/**
 
/**
 
  * HTML View class for the HelloWorld Component
 
  * HTML View class for the HelloWorld Component
 +
*
 +
* @since  0.0.1
 
  */
 
  */
class HelloWorldViewHelloWorld extends JView
+
class HelloWorldViewHelloWorld extends JViewLegacy
 
{
 
{
// Overwriting JView display method
+
/**
function display($tpl = null)  
+
* 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
 
// Assign data to the view
Line 91: Line 122:
 
}
 
}
 
}
 
}
 +
 
</source>
 
</source>
</span>
 
  
The ''display'' method of the ''[http://api.joomla.org/Joomla-Platform/Application/JView.html JView]'' class is called with the ''display'' task of the JController class. In our case, this method will display data using the ''tmpl/default.php'' file. With your favorite file manager and editor, create a file ''site/views/helloworld/tmpl/default.php'' able to display the default view and containing
+
The ''display'' method of the ''[https://api.joomla.org/cms-3/classes/JViewLegacy.html JViewLegacy]'' class is called with the ''display'' task of the JControllerLegacy class. In our case, this method will display data using the ''tmpl/default.php'' file. With your favorite file manager and editor, create a file '''''yoursite/components/com_helloworld/views/helloworld/tmpl/default.php''''' able to display the default view and containing:
  
<span id="site/views/helloworld/tmpl/default.php">
 
''site/views/helloworld/tmpl/default.php''
 
 
<source lang="php">
 
<source lang="php">
 
<?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
 
// No direct access to this file
 
defined('_JEXEC') or die('Restricted access');
 
defined('_JEXEC') or die('Restricted access');
 
?>
 
?>
 
<h1><?php echo $this->msg; ?></h1>
 
<h1><?php echo $this->msg; ?></h1>
 +
 
</source>
 
</source>
  
This template file will be included by the JView class. Therefore, here, $this refers to the HelloWorldViewHelloWorld class.
+
This template file will be included by the JViewLegacy class. Therefore, here, $this refers to the HelloWorldViewHelloWorld class.
 +
 
 +
 
 +
So to give an example, one could call the view inside the ''yoursite/components/com_[component_name]/views/[name of view]/'' folder by calling <code>index.php?option=com_helloworld</code> (this would default to the ''yoursite/components/com_helloworld/views/helloworld/'' folder) or we could explicitly call the folder by calling: <code>index.php?option=com_helloworld&view=helloworld</code>
 +
 
 +
if we change <code>&view=helloworld</code> to something else, e.g. <code>&view=fluffy</code> we would have to create a folder <code>components/com_helloworld/views/fluffy/</code>.
 +
 
 +
Copy the contents of <code>views/helloworld</code> to <code>views/fluffy</code>
 +
 
 +
The classname of the file <code>view.html.php</code> of the fluffy folder would be ''HelloWorldViewFluffy''. Afterwards you can customize the contents of ''default.php'' of the ''fluffy'' subfolder for custom output and see the output by calling <code>index.php?option=com_helloworld&view=fluffy</code>
  
 
== Packaging the component ==
 
== Packaging the component ==
Line 112: Line 159:
 
Content of your code directory
 
Content of your code directory
 
* ''[[#helloworld.xml|helloworld.xml]]''
 
* ''[[#helloworld.xml|helloworld.xml]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|site/index.html]]''
 
 
* ''[[#site/helloworld.php|site/helloworld.php]]''
 
* ''[[#site/helloworld.php|site/helloworld.php]]''
 +
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/index.html]]''
 
* ''[[#site/controller.php|site/controller.php]]''
 
* ''[[#site/controller.php|site/controller.php]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|site/views/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/index.html]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|site/views/helloworld/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/index.html]]''
 
* ''[[#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
 
* ''[[#site/views/helloworld/view.html.php|site/views/helloworld/view.html.php]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|site/views/helloworld/tmpl/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|site/views/helloworld/tmpl/index.html]]''
 
* ''[[#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
 
* ''[[#site/views/helloworld/tmpl/default.php|site/views/helloworld/tmpl/default.php]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|admin/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/index.html]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#admin/helloworld.php|admin/helloworld.php]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#admin/helloworld.php|admin/helloworld.php]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|admin/sql/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/index.html]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|admin/sql/updates/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/index.html]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#index.html|admin/sql/updates/mysql/index.html]]''
+
* ''[[J3.2:Developing_a_MVC_Component/Developing_a_Basic_Component#index.html|admin/sql/updates/mysql/index.html]]''
* ''[[Developing_a_Model-View-Controller_(MVC)_Component_for_Joomla!2.5_-_Part_01#admin/sql/updates/mysql/0.0.1.sql|admin/sql/updates/mysql/0.0.1.sql]]''
+
* ''[[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 [http://joomlacode.org/gf/download/frsrelease/11394/58226/com_helloworld-1.6-part02.zip archive] and install it using the extension manager of Joomla. You can test this basic component by putting ''index.php?option=com_helloworld'' in your browser address.
+
Create a compressed file of this directory or directly download the [https://github.com/scionescire/Joomla-3.2-Hello-World-Component/archive/step-2-adding-a-site-view.zip archive] and install it using the extension manager of Joomla. You can test this basic component by putting ''index.php?option=com_helloworld'' in your browser address.
  
 
<span id="helloworld.xml">
 
<span id="helloworld.xml">
 
''helloworld.xml''
 
''helloworld.xml''
<source lang="xml">
+
<source lang="xml" highlight="13,30,31">
 
<?xml version="1.0" encoding="utf-8"?>
 
<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="2.5.0" method="upgrade">
+
<extension type="component" version="3.2.0" method="upgrade">
  
 
<name>Hello World!</name>
 
<name>Hello World!</name>
 
<!-- The following elements are optional and free of formatting constraints -->
 
<!-- The following elements are optional and free of formatting constraints -->
<creationDate>November 2009</creationDate>
+
<creationDate>December 2013</creationDate>
 
<author>John Doe</author>
 
<author>John Doe</author>
 
<authorEmail>john.doe@example.org</authorEmail>
 
<authorEmail>john.doe@example.org</authorEmail>
Line 148: Line 195:
 
<description>Description of the Hello World component ...</description>
 
<description>Description of the Hello World component ...</description>
  
<update> <!-- Runs on update; New in 2.5 -->
+
<update> <!-- Runs on update; New since J2.5 -->
 
<schemas>
 
<schemas>
 
<schemapath type="mysql">sql/updates/mysql</schemapath>
 
<schemapath type="mysql">sql/updates/mysql</schemapath>
Line 167: Line 214:
 
<administration>
 
<administration>
 
<!-- Administration Menu Section -->
 
<!-- Administration Menu Section -->
<menu>Hello World!</menu>
+
<menu link='index.php?option=com_helloworld'>Hello World!</menu>
 
<!-- Administration Main File Copy Section -->
 
<!-- Administration Main File Copy Section -->
 
<!-- Note the folder attribute: This attribute describes the folder
 
<!-- Note the folder attribute: This attribute describes the folder
Line 188: Line 235:
 
You will see by default the message contained in the variable ''$this->msg'' in the ''view.html.php'' file.
 
You will see by default the message contained in the variable ''$this->msg'' in the ''view.html.php'' file.
  
== Navigate ==
+
{{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.}}
  
[[Developing a Model-View-Controller (MVC) Component for Joomla!2.5 - Part 01|Prev: Developing a Basic Component]] [[Developing a Model-View-Controller (MVC) Component for Joomla!2.5 - Part 03|Next: Adding a menu type to the site part]]
+
{{:J3.2:Developing a MVC Component/Navigate|prev=Developing a Basic Component|next=Adding a menu type to the site part}}
 +
 
 +
<noinclude>[[Category:Component Development]] [[Category:Joomla! 3.0]] [[Category:Joomla! 3.1]][[Category:Joomla! 3.2]]</noinclude>
  
 
== Contributors ==
 
== Contributors ==
 +
 +
*[[User:Gunjanpatel|Gunjan Patel]]
 
*[[User:cdemko|Christophe Demko]]
 
*[[User:cdemko|Christophe Demko]]
 
*[[User:oaksu|Ozgur Aksu]]
 
*[[User:oaksu|Ozgur Aksu]]
 +
*[[User:Scionescire|Scionescire]]
  
 
[[Category:Development]]
 
[[Category:Development]]

Revision as of 06:50, 21 April 2015

<translate> Articles in This Series</translate>

  1. <translate>

Introduction</translate>

  1. <translate>

Developing a Basic Component</translate>

  1. <translate>

Adding a View to the Site Part</translate>

  1. <translate>

Adding a Menu Type to the Site Part</translate>

  1. <translate>

Adding a Model to the Site Part</translate>

  1. <translate>

Adding a Variable Request in the Menu Type</translate>

  1. <translate>

Using the Database</translate>

  1. <translate>

Basic Backend</translate>

  1. <translate>

Adding Language Management</translate>

  1. <translate>

Adding Backend Actions</translate>

  1. <translate>

Adding Decorations to the Backend</translate>

  1. <translate>

Adding Verifications</translate>

  1. <translate>

Adding Categories</translate>

  1. <translate>

Adding Configuration</translate>

  1. <translate>

Adding ACL</translate>

  1. <translate>

Adding an Install/Uninstall/Update Script File</translate>

  1. <translate>

Adding a Frontend Form</translate>

  1. <translate> Adding an Image</translate>
  2. <translate> Adding a Map</translate>
  3. <translate> Adding AJAX</translate>
  4. <translate> Adding an Alias</translate>
  5. <translate>

Using the Language Filter Facility</translate>

  1. <translate> Adding a Modal</translate>
  2. <translate> Adding Associations</translate>
  3. <translate> Adding Checkout</translate>
  4. <translate> Adding Ordering</translate>
  5. <translate> Adding Levels</translate>
  6. <translate> Adding Versioning</translate>
  7. <translate> Adding Tags</translate>
  8. <translate> Adding Access</translate>
  9. <translate> Adding a Batch Process</translate>
  10. <translate> Adding Cache</translate>
  11. <translate> Adding a Feed</translate>
  12. <translate>

Adding an Update Server</translate>

  1. <translate> Adding Custom Fields</translate>
  2. <translate> Upgrading to Joomla4</translate>



Introduction[edit]

This tutorial is part of the Developing a Model-View-Controller (MVC) Component for Joomla! 3.x tutorial. You are encouraged to read the previous parts of the tutorial before reading this.

In the Joomla!3.x framework, third party component authors divide their code into three main parts:

  • models They manage the data
  • controllers They perform tasks, set and get the states of the models and ask the views to display
  • views They display the content according to the type (error, feed, html, json, raw, xml) and the layout chosen by the controllers

Setting the controller[edit]

In the core code of Joomla, there is a class able to manage controllers: JControllerLegacy. This class has to be extended to be used in our component. In the file yoursite/components/com_helloworld/helloworld.php (entry point of our Hello World component), put these lines:

site/helloworld.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');

// 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();

The getInstance static method of the JControllerLegacy class will create a controller. In the code above, it will instantiate a controller object of a class named HelloWorldController. Joomla will look for the declaration of that class in an aptly named file called yoursite/components/com_helloworld/controller.php (it's a default behavior).

Now, controller.php needs to be created and HelloWorldController needs to be declared and defined. So with your favorite file manager and editor, create a yoursite/components/com_helloworld/controller.php file containing

site/controller.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');
/**
 * Hello World Component Controller
 *
 * @since  0.0.1
 */
class HelloWorldController extends JControllerLegacy
{
}

When no task is given in the request variables, the default task will be executed. It's the display task by default. The JControllerLegacy class has such a task. In our example, it will display a view named HelloWorld.

So with task simply a public function display() of JControllerLegacy is refered to.


A Tip!

Just a side note for completion, you could call another function aside from display() by using an URL like this one:

http://localhost/index.php?option=com_helloworld&task=insert
This would try to call a function insert() of our controller (which we would actually have to implement in HelloWorldController ).

Setting the view[edit]

When JControllerLegacy wants to display a view, it will look for certain files in the yoursite/components/com_[component_name]/views/[name of view]/ folder.

The name of the folder of the default view is the name of the component itself. In our case the path is yoursite/components/com_helloworld/views/helloworld/.

The file that will contain the code of the view is called view.[view_mode].php. The default view mode, and probably the only view a component might need is the html mode. So this give us our file name which is view.html.php.

With your favorite file manager and editor, create a file yoursite/components/com_helloworld/views/helloworld/view.html.php able to display the default view and containing:

<?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 = 'Hello World';

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

The display method of the JViewLegacy class is called with the display task of the JControllerLegacy class. In our case, this method will display data using the tmpl/default.php file. With your favorite file manager and editor, create a file yoursite/components/com_helloworld/views/helloworld/tmpl/default.php able to display the default view and containing:

<?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');
?>
<h1><?php echo $this->msg; ?></h1>

This template file will be included by the JViewLegacy class. Therefore, here, $this refers to the HelloWorldViewHelloWorld class.


So to give an example, one could call the view inside the yoursite/components/com_[component_name]/views/[name of view]/ folder by calling index.php?option=com_helloworld (this would default to the yoursite/components/com_helloworld/views/helloworld/ folder) or we could explicitly call the folder by calling: index.php?option=com_helloworld&view=helloworld

if we change &view=helloworld to something else, e.g. &view=fluffy we would have to create a folder components/com_helloworld/views/fluffy/.

Copy the contents of views/helloworld to views/fluffy

The classname of the file view.html.php of the fluffy folder would be HelloWorldViewFluffy. Afterwards you can customize the contents of default.php of the fluffy subfolder for custom output and see the output by calling index.php?option=com_helloworld&view=fluffy

Packaging the component[edit]

Content of your code directory

Create a compressed file of this directory or directly download the archive and install it using the extension manager of Joomla. You can test this basic component by putting index.php?option=com_helloworld in your browser address.

helloworld.xml

<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.2.0" method="upgrade">

	<name>Hello World!</name>
	<!-- The following elements are optional and free of formatting constraints -->
	<creationDate>December 2013</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>
	<!--  The version string is recorded in the components table -->
	<version>0.0.2</version>
	<!-- The description is optional and defaults to the name -->
	<description>Description of the Hello World component ...</description>

	<update> <!-- Runs on update; New since J2.5 -->
		<schemas>
			<schemapath type="mysql">sql/updates/mysql</schemapath>
		</schemas>
	</update>

	<!-- Site Main File Copy Section -->
	<!-- Note the folder attribute: This attribute describes the folder
		to copy FROM in the package to install therefore files copied
		in this section are copied from /site/ in the package -->
	<files folder="site">
		<filename>index.html</filename>
		<filename>helloworld.php</filename>
		<filename>controller.php</filename>
		<folder>views</folder>
	</files>

	<administration>
		<!-- Administration Menu Section -->
		<menu link='index.php?option=com_helloworld'>Hello World!</menu>
		<!-- Administration Main File Copy Section -->
		<!-- Note the folder attribute: This attribute describes the folder
			to copy FROM in the package to install therefore files copied
			in this section are copied from /admin/ in the package -->
		<files folder="admin">
			<!-- Admin Main File Copy Section -->
			<filename>index.html</filename>
			<filename>helloworld.php</filename>
			<!-- SQL files section -->
			<folder>sql</folder>
		</files>
	</administration>

</extension>

Result: You will see by default the message contained in the variable $this->msg in the view.html.php file.

Info non-talk.png
General Information

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.x:Developing a MVC Component/Navigate

Contributors[edit]