view.php

Joomla!是一套获得过多个奖项的内容管理系统(Content Management System, CMS)。Joomla!采用PHP+MySQL数据库开发

<?php
/**
 * @version		$Id: view.php 10381 2008-06-01 03:35:53Z pasamio $
 * @package		Joomla.Framework
 * @subpackage	Application
 * @copyright Copyright Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.
 * @license		GNU/GPL, see LICENSE.php
 * Joomla! is free software. This version may have been modified pursuant
 * to the GNU General Public License, and as distributed it includes or
 * is derivative of works licensed under the GNU General Public License or
 * other free or open source software licenses.
 * See COPYRIGHT.php for copyright notices and details.
 */

// Check to ensure this file is within the rest of the framework
defined('JPATH_BASE') or die();

/**
 * Base class for a Joomla View
 *
 * Class holding methods for displaying presentation data.
 *
 * @abstract
 * @package		Joomla.Framework
 * @subpackage	Application
 * @since		1.5
 */
class JView extends JObject
{
	/**
	 * The name of the view
	 *
	 * @var		array
	 * @access protected
	 */
	var $_name = null;

	/**
	 * Registered models
	 *
	 * @var		array
	 * @access protected
	 */
	var $_models = array();

	/**
	 * The base path of the view
	 *
	 * @var		string
	 * @access 	protected
	 */
	var $_basePath = null;

	/**
	 * The default model
	 *
	 * @var	string
	 * @access protected
	 */
	var $_defaultModel = null;

	/**
	 * Layout name
	 *
	 * @var		string
	 * @access 	protected
	 */
	var $_layout = 'default';

	/**
	 * Layout extension
	 *
	 * @var		string
	 * @access 	protected
	 */
	var $_layoutExt = 'php';

	/**
	* The set of search directories for resources (templates)
	*
	* @var array
	* @access protected
	*/
	var $_path = array(
		'template' => array(),
		'helper' => array()
	);

	/**
	* The name of the default template source file.
	*
	* @var string
	* @access private
	*/
	var $_template = null;

	/**
	* The output of the template script.
	*
	* @var string
	* @access private
	*/
	var $_output = null;

	/**
     * Callback for escaping.
     *
     * @var string
     * @access private
     */
    var $_escape = 'htmlspecialchars';

	 /**
     * Charset to use in escaping mechanisms; defaults to urf8 (UTF-8)
     *
     * @var string
     * @access private
     */
    var $_charset = 'UTF-8';

	/**
	 * Constructor
	 *
	 * @access	protected
	 */
	function __construct($config = array())
	{
		//set the view name
		if (empty( $this->_name ))
		{
			if (array_key_exists('name', $config))  {
				$this->_name = $config['name'];
			} else {
				$this->_name = $this->getName();
			}
		}

		 // set the charset (used by the variable escaping functions)
        if (array_key_exists('charset', $config)) {
            $this->_charset = $config['charset'];
        }

		 // user-defined escaping callback
        if (array_key_exists('escape', $config)) {
            $this->setEscape($config['escape']);
        }

		// Set a base path for use by the view
		if (array_key_exists('base_path', $config)) {
			$this->_basePath	= $config['base_path'];
		} else {
			$this->_basePath	= JPATH_COMPONENT;
		}

		// set the default template search path
		if (array_key_exists('template_path', $config)) {
			// user-defined dirs
			$this->_setPath('template', $config['template_path']);
		} else {
			$this->_setPath('template', $this->_basePath.DS.'views'.DS.$this->getName().DS.'tmpl');
		}

		// set the default helper search path
		if (array_key_exists('helper_path', $config)) {
			// user-defined dirs
			$this->_setPath('helper', $config['helper_path']);
		} else {
			$this->_setPath('helper', $this->_basePath.DS.'helpers');
		}

		// set the layout
		if (array_key_exists('layout', $config)) {
			$this->setLayout($config['layout']);
		} else {
			$this->setLayout('default');
		}

		$this->baseurl = JURI::base(true);
	}

	/**
	* Execute and display a template script.
	*
	* @param string $tpl The name of the template file to parse;
	* automatically searches through the template paths.
	*
	* @throws object An JError object.
	* @see fetch()
	*/
	function display($tpl = null)
	{
		$result = $this->loadTemplate($tpl);
		if (JError::isError($result)) {
			return $result;
		}

		echo $result;
	}

	/**
	* Assigns variables to the view script via differing strategies.
	*
	* This method is overloaded; you can assign all the properties of
	* an object, an associative array, or a single value by name.
	*
	* You are not allowed to set variables that begin with an underscore;
	* these are either private properties for JView or private variables
	* within the template script itself.
	*
	* <code>
	* $view = new JView();
	*
	* // assign directly
	* $view->var1 = 'something';
	* $view->var2 = 'else';
	*
	* // assign by name and value
	* $view->assign('var1', 'something');
	* $view->assign('var2', 'else');
	*
	* // assign by assoc-array
	* $ary = array('var1' => 'something', 'var2' => 'else');
	* $view->assign($obj);
	*
	* // assign by object
	* $obj = new stdClass;
	* $obj->var1 = 'something';
	* $obj->var2 = 'else';
	* $view->assign($obj);
	*
	* </code>
	*
	* @access public
	* @return bool True on success, false on failure.
	*/
	function assign()
	{
		// get the arguments; there may be 1 or 2.
		$arg0 = @func_get_arg(0);
		$arg1 = @func_get_arg(1);

		// assign by object
		if (is_object($arg0))
		{
			// assign public properties
			foreach (get_object_vars($arg0) as $key => $val)
			{
				if (substr($key, 0, 1) != '_') {
					$this->$key = $val;
				}
			}
			return true;
		}

		// assign by associative array
		if (is_array($arg0))
		{
			foreach ($arg0 as $key => $val)
			{
				if (substr($key, 0, 1) != '_') {
					$this->$key = $val;
				}
			}
			return true;
		}

		// assign by string name and mixed value.

		// we use array_key_exists() instead of isset() becuase isset()
		// fails if the value is set to null.
		if (is_string($arg0) && substr($arg0, 0, 1) != '_' && func_num_args() > 1)
		{
			$this->$arg0 = $arg1;
			return true;
		}

		// $arg0 was not object, array, or string.
		return false;
	}


	/**
	* Assign variable for the view (by reference).
	*
	* You are not allowed to set variables that begin with an underscore;
	* these are either private properties for JView or private variables
	* within the template script itself.
	*
	* <code>
	* $view = new JView();
	*
	* // assign by name and value
	* $view->assignRef('var1', $ref);
	*
	* // assign directly
	* $view->ref =& $var1;
	* </code>
	*
	* @access public
	*
	* @param string $key The name for the reference in the view.
	* @param mixed &$val The referenced variable.
	*
	* @return bool True on success, false on failure.
	*/

	function assignRef($key, &$val)
	{
		if (is_string($key) && substr($key, 0, 1) != '_')
		{
			$this->$key =& $val;
			return true;
		}

		return false;
	}

	/**
     * Escapes a value for output in a view script.
     *
     * If escaping mechanism is one of htmlspecialchars or htmlentities, uses
     * {@link $_encoding} setting.
     *
     * @param  mixed $var The output to escape.
     * @return mixed The escaped value.
     */
    function escape($var)
    {
        if (in_array($this->_escape, array('htmlspecialchars', 'htmlentities'))) {
            return call_user_func($this->_escape, $var, ENT_COMPAT, $this->_charset);
        }

        return call_user_func($this->_escape, $var);
    }

	/**
	 * Method to get data from a registered model or a property of the view
	 *
	 * @access	public
	 * @param	string	The name of the method to call on the model, or the property to get
	 * @param	string	The name of the model to reference, or the default value [optional]
	 * @return mixed	The return value of the method
	 */
	function &get( $property, $default = null )
	{