Joomla! Documentation™

Joomla! 

3.x

教學

開發一個 Model-View-Controller 元件

本系列文章

1. 介紹
2. 開發一個基本的元件

新增前台的 view

新增一個選單類型到前台

新增一個 model 到前台

在選單類型中新增一個變數請求

使用資料庫

基本的後台

新增語言管理

新增後台行為

新增後台的佈置

新增表單驗證

新增類別

新增設定介面

1. 新增 ACL

新增一個安裝/移除/更新程式碼檔案

新增一個前台表單

1. 新增一個圖片
2. 新增一個 map
3. 新增 AJAX
4. 新增一個別名

使用語言過濾功能

1. 新增一個 model
2. 新增關聯
3. 新增回存
4. 新增排序
5. 新增階層
6. 新增版本控制
7. 新增標籤
8. 新增存取權限
9. 新增批次作業
10. 新增快取
11. 新增 Feed

新增更新伺服器

1. 新增客製化欄位
2. Upgrading to Joomla4

這是一系列的多篇文章，旨在介紹如何開發一個 Joomla! Version Model-View-Controller 元件

讓我們從簡介開始，您可以使用底下的導覽按鈕來瀏覽文章，或是右側的方塊中的連結(列出所有的文章)。

介紹

• 本教學是 開發Joomla! 3.x MVC 元件 系列文章的一部分，閱讀本文之前，您應該先看過前面幾篇文章。

有兩隻影片和此步驟教學有關： MVC 結構以及分頁效果 (Pagination), 以及 HTML 元素以及 Javascript 程式碼.

基本的後台

Designing the backend interface leads us to create at least a Model-View-Controller triptych. We have to modify the administrator entry point of our component, the admin/helloworld.php file.

admin/helloworld.php

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 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
$controller->execute(JFactory::getApplication()->input->get('task'));

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

Create the general controller

The entry point now gets an instance of a HelloWorld prefixed controller. Let's create a basic controller for the administrator part:

admin/controller.php

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 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');

/**
 * General Controller of HelloWorld component
 *
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 * @since       0.0.7
 */
class HelloWorldController extends JControllerLegacy
{
	/**
	 * The default view for the display method.
	 *
	 * @var string
	 * @since 12.2
	 */
	protected $default_view = 'helloworlds';
}

預設 controller 將會顯示 'HelloWorlds' 的 view。

建立 view

With your favourite file manager and editor, create a file admin/views/helloworlds/view.html.php containing:

admin/views/helloworlds/view.html.php

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 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 data from the model
		$this->items		= $this->get('Items');
		$this->pagination	= $this->get('Pagination');

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

			return false;
		}

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

In Joomla, views display data using layout. With your favourite file manager and editor, put a file admin/views/helloworlds/tmpl/default.php containing

admin/views/helloworlds/tmpl/default.php

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 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');
?>
<form action="index.php?option=com_helloworld&view=helloworlds" method="post" id="adminForm" name="adminForm">
	<table class="table table-striped table-hover">
		<thead>
		<tr>
			<th width="1%"><?php echo JText::_('COM_HELLOWORLD_NUM'); ?></th>
			<th width="2%">
				<?php echo JHtml::_('grid.checkall'); ?>
			</th>
			<th width="90%">
				<?php echo JText::_('COM_HELLOWORLD_HELLOWORLDS_NAME') ;?>
			</th>
			<th width="5%">
				<?php echo JText::_('COM_HELLOWORLD_PUBLISHED'); ?>
			</th>
			<th width="2%">
				<?php echo JText::_('COM_HELLOWORLD_ID'); ?>
			</th>
		</tr>
		</thead>
		<tfoot>
			<tr>
				<td colspan="5">
					<?php echo $this->pagination->getListFooter(); ?>
				</td>
			</tr>
		</tfoot>
		<tbody>
			<?php if (!empty($this->items)) : ?>
				<?php foreach ($this->items as $i => $row) : ?>

					<tr>
						<td>
							<?php echo $this->pagination->getRowOffset($i); ?>
						</td>
						<td>
							<?php echo JHtml::_('grid.id', $i, $row->id); ?>
						</td>
						<td>
							<?php echo $row->greeting; ?>
						</td>
						<td align="center">
							<?php echo JHtml::_('jgrid.published', $row->published, $i, 'helloworlds.', true, 'cb'); ?>
						</td>
						<td align="center">
							<?php echo $row->id; ?>
						</td>
					</tr>
				<?php endforeach; ?>
			<?php endif; ?>
		</tbody>
	</table>
</form>

COM_HELLOWORLD_HELLOWORLDS_NAME, COM_HELLOWORLD_ID and the others are placeholders which will later be replaced with language-specific text. The JText::_ method translates a string into the current language.

checkAll is a javascript function defined in the Joomla core able to check all items.

JHtml::_ is a helper function able to display several HTML output. In this case, it will display a checkbox for the item.

JPagination is a Joomla class able to manage and display pagination object.

建立 model

The HelloWorlds view asks the model for data. In Joomla, there is a class able to manage a list of data: JModelList. Class JModelList and inherited classes need only one method:

• getListQuery which constructs an SQL query

以及兩個 states：

• list.start for determining the list offset
• list.limit for determining the list length

The getItems and getPagination methods are defined in JModelList class. They don't need to be defined in the HelloWorldModelHelloWorlds class.

admin/models/helloworlds.php

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 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');

/**
 * HelloWorldList Model
 *
 * @since  0.0.1
 */
class HelloWorldModelHelloWorlds extends JModelList
{
	/**
	 * Method to build an SQL query to load the list data.
	 *
	 * @return      string  An SQL query
	 */
	protected function getListQuery()
	{
		// Initialize variables.
		$db    = JFactory::getDbo();
		$query = $db->getQuery(true);

		// Create the base select statement.
		$query->select('*')
                ->from($db->quoteName('#__helloworld'));

		return $query;
	}
}

The _populateState method is, by default, automatically called when a state is read by the getState method.

包裝元件

您的程式碼路徑中的內容

• helloworld.xml
• site/helloworld.php
• site/index.html
• site/controller.php
• site/views/index.html
• site/views/helloworld/index.html
• site/views/helloworld/view.html.php
• site/views/helloworld/tmpl/index.html
• site/views/helloworld/tmpl/default.xml
• site/views/helloworld/tmpl/default.php
• site/models/index.html
• site/models/helloworld.php
• admin/index.html
• admin/helloworld.php
• admin/controller.php
• admin/sql/index.html
• admin/sql/install.mysql.utf8.sql
• admin/sql/uninstall.mysql.utf8.sql
• admin/sql/updates/index.html
• admin/sql/updates/mysql/index.html
• admin/sql/updates/mysql/0.0.1.sql
• admin/sql/updates/mysql/0.0.6.sql
• admin/models/index.html
• admin/models/fields/index.html
• admin/models/fields/helloworld.php
• admin/models/helloworlds.php
• admin/views/index.html
• admin/views/helloworlds/index.html
• admin/views/helloworlds/view.html.php
• admin/views/helloworlds/tmpl/index.html
• admin/views/helloworlds/tmpl/default.php
• admin/tables/index.html
• admin/tables/helloworld.php

Create a compressed file of this directory or directly download the 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.

helloworld.xml

<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.0" method="upgrade">

	<name>Hello World!</name>
	<!-- The following elements are optional and free of formatting constraints -->
	<creationDate>January 2018</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>0.0.7</version>
	<!-- The description is optional and defaults to the name -->
	<description>Description of the Hello World component ...</description>

	<install> <!-- Runs on install -->
		<sql>
			<file driver="mysql" charset="utf8">sql/install.mysql.utf8.sql</file>
		</sql>
	</install>
	<uninstall> <!-- Runs on uninstall -->
		<sql>
			<file driver="mysql" charset="utf8">sql/uninstall.mysql.utf8.sql</file>
		</sql>
	</uninstall>
	<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>
		<folder>models</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>
			<filename>controller.php</filename>
			<!-- SQL files section -->
			<folder>sql</folder>
			<!-- tables files section -->
			<folder>tables</folder>
			<!-- models files section -->
			<folder>models</folder>
			<!-- views files section -->
			<folder>views</folder>
		</files>
	</administration>

</extension>

Now you can see in your component hello-world an array with two colums, two rows and checkboxes. You can click the checkboxes in order to select the different options you want.

General Information

貢獻者

• Gunjan Patel
• Christophe Demko
• Ozgur Aksu
• Preston Smith
• Scionescire

上一篇：使用資料庫

下一篇：新增語言管理