Create "Hello world" Plugin in Joomla 3.0

Hello all,

I am writing this blog as a tutorial to write Joomla! 3.0 plugin. you can download files from here .download files

How to create a Hello World content plugin for Joomla 3.0

Written by Zeel Shah

This plugin will print "Hello World!" at the beginning of every article. This plugin is of group ‘content’ as we are dealing with articles.  

Step 1: Create the Plugin Files

All Joomla 2.5 plugins contain a xml file. These xml files contain information such as who wrote the plugin and when, what files should be included with the plugin, and any plugin settings that can be adjusted. The first thing you should do is copy the following text and save it as helloworld.xml

<?xml version="1.0" encoding="utf-8"?>

<extension version="3.0" type="plugin" group="content">

        <name>plg_content_helloworld</name>

        <author>Zeel shah</author>

            <creationDate>2012-10-21</creationDate>

        <copyright>zps</copyright>

        <license>GNU General Public License</license>

        <authorEmail>kshah215@gmail.com</authorEmail>

        <authorUrl>www.magnificientzps.blogspot.com</authorUrl>

        <version>1.0</version>

        <description>Simple Hello World Plugin that prints "Hello World" at the beginning of every article.</description>

        <files>

                <filename plugin="helloworld">helloworld.php</filename>

                <filename>index.html</filename>

        </files>

</extension>

After creating the XML file, we now need to create our php file, which does all of the work. The following code should be saved to helloworld.php

<?php

// no direct access

defined('_JEXEC') or die;

class plgContentHelloworld extends JPlugin

{

    public function onContentAfterTitle($context, &$article, &$params, $limitstart)

        {

                return "<p>Hello World!</p>";

        }

}

?>

The last file we need to create is one named index.html. You don't need to place any code in the file, you simply need to create it.

At this stage, you should have the following files:

·         helloworld.xml

·         helloworld.php

·         index.html

Compress all of these files into a zip file named helloworld.zip

 Step 2: Install the Plugin

 Step 3: Enable and Test your new Plugin

When you initially install the plugin, it will be disabled, so be sure to enable the plugin.

Because we're using theonContentAfterTitle event, we need to set the article's Show Intro Text value to Hide 

Visit any Joomla 2.5 article, and you should see "Hello World!" printed after the title, as in the following screenshot to the right.

Because we used the onContentAfterTitle event, our "Hello World" message is being shown on the content and after the title has been printed.

See here you can see hello world after the title. :