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

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< J3.x:Developing a MVC Component
(Merging useful tips from v.2.5 made by Jossnaz)
m (Added "/" at the end of <schemapath> text)
(10 intermediate revisions by 5 users not shown)
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== Setting the controller ==
 
== Setting the controller ==
In the core code of Joomla, there is a class able to manage controllers: ''[http://api.joomla.org/cms-3/classes/JControllerLegacy.html JControllerLegacy]''. 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: ''[http://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}}
Line 33: Line 33:
 
</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 ''[http://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}}
Line 54: Line 54:
 
</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 ''JController'' is refered to.
+
So with ''task'' simply a public function display() of ''JControllerLegacy'' is refered to.
  
  
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== 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
Line 101: Line 99:
 
}
 
}
 
</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 ''[http://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
Line 115: Line 110:
 
</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 ''component/com_[component_name]/views/[name of view]/''    folder by calling:
+
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>
  
http://localhost/joomla/index.php?option=com_helloworld
+
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>.
  
(this would default to the ''component/com_helloworld/views/helloworld/'' folder)
+
Copy the contents of <code>views/helloworld</code> to <code>views/fluffy</code>
or we could explicitly call the folder by calling
+
  
http://localhost/joomla/index.php?option=com_helloworld&view=helloworld
+
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>
 
+
if we change ''&view=helloworld'' to something else, e.g. ''&view=fluffy'' we would have to create a folder:
+
 
+
''component/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:
+
 
+
''http://localhost/joomla/index.php?option=com_helloworld&view=fluffy''
+
  
 
== Packaging the component ==
 
== Packaging the component ==
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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 [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.
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<update> <!-- Runs on update; New in 2.5 -->
 
<update> <!-- Runs on update; New in 2.5 -->
 
<schemas>
 
<schemas>
<schemapath type="mysql">sql/updates/mysql</schemapath>
+
<schemapath type="mysql">sql/updates/mysql/</schemapath>
 
</schemas>
 
</schemas>
 
</update>
 
</update>
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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.}}
 +
 
 +
{{:J3.2:Developing a MVC Component/Navigate|prev=Developing a Basic Component|next=Adding a menu type to the site part}}
  
[[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]]
+
<noinclude>[[Category:Component Development]] [[Category:Joomla! 3.0]] [[Category:Joomla! 3.1]][[Category:Joomla! 3.2]]</noinclude>
  
 
== Contributors ==
 
== Contributors ==

Revision as of 19:56, 17 May 2014


Introduction

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

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
// No direct access to this file
defined('_JEXEC') or die('Restricted access');
 
// import joomla controller library
jimport('joomla.application.component.controller');
 
// 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
// No direct access to this file
defined('_JEXEC') or die('Restricted access');
 
// import Joomla controller library
jimport('joomla.application.component.controller');
 
/**
 * Hello World Component Controller
 */
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.


Tip-icon.png
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

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
// No direct access to this file
defined('_JEXEC') or die('Restricted access');
 
// import Joomla view library
jimport('joomla.application.component.view');
 
/**
 * HTML View class for the HelloWorld Component
 */
class HelloWorldViewHelloWorld extends JViewLegacy
{
        // Overwriting JView display method
        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
// 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

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="2.5.0" method="upgrade">
 
        <name>Hello World!</name>
        <!-- The following elements are optional and free of formatting constraints -->
        <creationDate>November 2009</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 in 2.5 -->
                <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>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.


Tutorial Navigation

Contributors