J4.x

Developing an MVC Component/Language Management

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< J4.x:Developing an MVC Component
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4.x
>Tutorial
Adding Language Management


This article is part of the tutorial "Developing an MVC Component for Joomla 4.x". It is intended to be a follow-along programming tutorial, so if you have not read the previous parts of the tutorial you are encouraged to do so.

Basic Language Management

In this article we will add management for language strings to our new component. You may have noticed in the last article in this tutorial series that when we added a menu link to the component, we hard-coded English words into the link:

<?xml version="1.0" encoding="utf-8"?>
<metadata>
    <layout title="Hello World!">
        <message><![CDATA[My first Joomla! page]]></message>
    </layout>
</metadata>

This works as an initial test, but hard-coding a single language into the system is a bad idea. Before we get too far into building pages and forms, we should add multi-language support to the component.

Even if you do not personally have the resources to perform translations yourself, we highly recommend that you are diligent about correctly managing your language strings inside your component. Open source components can be translated by members of the community, and end users can create their own if they so wish.

Let's create the language files and update the manifest to reference them:

1 Create: admin/language/en-GB/en-GB.com_helloworld.ini Component language strings for the admin panel part
2 Create: admin/language/en-GB/en-GB.com_helloworld.sys.ini System language strings for the component
3 Create: site/language/en-GB/en-GB.com_helloworld.ini Component language strings for the public site part
4 Update: helloworld.xml Need to add the language files to the manifest
5 Update: admin/tmpl/hello/default.php Swap hard-coded language strings for language codes
6 Update: site/tmpl/hello/default.php Swap hard-coded language strings for language codes
7 Update: site/tmpl/hello/default.xml Swap hard-coded language strings for language codes

File Details

admin/language/en-GB/en-GB.com_helloworld.ini

This file contains the language strings used on the component's pages inside the admin panel of Joomla!

; Hello World Admin Strings
; Copyright (C) 2020 John Smith. All rights reserved.

COM_HELLOWORLD_MSG_HELLO_WORLD="Hello World!"

admin/language/en-GB/en-GB.com_helloworld.sys.ini

This file contains the language strings used in Joomla! systems outside the component's own pages. For example, our menu item's strings belong to this component, but are used by the Joomla! menu system rather than on our own pages, so they belong in this file.

; Hello World Sys.ini
; Copyright (C) 2020 John Smith. All rights reserved.

COM_HELLOWORLD_MENU_HELLO_WORLD_TITLE="Hello World!"
COM_HELLOWORLD_MENU_HELLO_WORLD_DESC="My first Joomla! page"

site/language/en-GB/en-GB.com_helloworld.ini

This file contains the language strings used on the component's "public" pages (pages in the site part). There's a few things to note that are common to all the language files you'll create. Firstly, language strings are stored in the common INI format, and the name of each property begins with the component's system name: com_helloworld. It is convention that all language properties are written in upper-case.

You'll also notice that both the folder and the language file itself contain the locale code for these strings, "en-GB". For each locale you wish to support, you will need a new set of files with the appropriate strings .

; Hello World Public Site Strings
; Copyright (C) 2020 John Smith. All rights reserved.

COM_HELLOWORLD_MSG_HELLO_WORLD="Hello World!"

helloworld.xml

As before, we need to add the new language folders to the manifest, so that Joomla! knows to copy them into place. Additionally, we need to tell Joomla! that we have language files, where to find them and what locales they support. This is done with the addition of two <language /> XML blocks, one for each part of the component.

<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="4.0" method="upgrade">

    <name>Hello World</name>
    <!-- The following elements are optional and free of formatting constraints -->
    <creationDate>December 2020</creationDate>
    <!-- Dummy author, feel free to replace anywhere you see it-->
    <author>John Smith</author>
    <authorUrl>https://smith.ca</authorUrl>
    <copyright>John Smith</copyright>
    <license>GPL v3</license>
    <!--  The version string is recorded in the components table -->
    <version>0.0.4</version>
    <!-- The description is optional and defaults to the name -->
    <description>
        A hello world component!
    </description>

    <!-- This is the PHP namespace under which the extension's
    code is organised. It should follow this format:
    
    Vendor\Component\ComponentName

    "Vendor" can be your company or your own name
    
    The "ComponentName" section MUST match the name used 
    everywhere else for your component. Whatever the name of 
    this XML file is, the namespace must match (ignoring CamelCase). 
    -->
    <namespace path="src/">JohnSmith\Component\HelloWorld</namespace>

    <files folder="site/">
        <folder>language</folder>
        <folder>src</folder>
        <folder>tmpl</folder>
    </files>

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

    <administration>
        <!-- The link that will appear in the Admin panel's "Components" menu -->
        <menu link="index.php?option=com_helloworld">Hello World</menu>
        <!-- List of files and folders to copy, and where to copy them -->
        <files folder="admin/">
            <folder>language</folder>
            <folder>services</folder>
            <folder>src</folder>
            <folder>tmpl</folder>
        </files>

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

</extension>

admin/tmpl/hello/default.php

Replace the hard-coded English strings with the new language properties. We use the Joomla\CMS\Language\Text class to output our language strings into the page. If the end user uses another language that is supported in our component, this class will automatically fetch the correct strings for that language and output those instead.

<?php

use Joomla\CMS\Language\Text;

/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2020 John Smith. All rights reserved.
 * @license     GNU General Public License version 3; see LICENSE
 */

 // No direct access to this file
defined('_JEXEC') or die('Restricted Access');
?>
<h2><?= Text::_('COM_HELLOWORLD_MSG_HELLO_WORLD') ?></h2>

site/tmpl/hello/default.php

Our page templates are currently identical, so the replacements required are also identical. Remove the hard-coded English and replace it with the correct language property.

<?php

use Joomla\CMS\Language\Text;

/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2020 John Smith. All rights reserved.
 * @license     GNU General Public License version 3; see LICENSE
 */

 // No direct access to this file
defined('_JEXEC') or die('Restricted Access');
?>
<h2><?= Text::_('COM_HELLOWORLD_MSG_HELLO_WORLD') ?></h2>

site/tmpl/hello/default.xml

Just like the PHP template files, we need to replace the hard-coded English in this file with the new language properties. Unlike the PHP files, however, we don't need any additional code to do so - simply replace the English strings with the language property names and Joomla! is clever enough to match them up for us.

Remember: because these strings are used by Joomla! in its own systems (outside of our component's pages), they live in the special admin/language/en-GB/en-GB.com_helloworld.sys.ini file.

<?xml version="1.0" encoding="utf-8"?>
<metadata>
    <layout title="COM_HELLOWORLD_MENU_HELLO_WORLD_TITLE">
        <message><![CDATA[COM_HELLOWORLD_MENU_HELLO_WORLD_DESC]]></message>
    </layout>
</metadata>

Testing the Component

Just as before, zip up your new component version and upload it into your Joomla! install's admin panel. Once it has installed, go around and make sure that your pages and menu link appear exactly as they did before. If everything is working properly, there should be no change at all.