chamilo-lms2/main/inc/lib/app_view.php

<?php
/* For licensing terms, see /license.txt */

/**
 * Class View
 */
class View
{
    private $data;
    private $template;
    private $layout;
    private $tool_path;

    /**
     * Constructor, init tool path for rendering
     * @param string $toolname tool name (optional)
     * @param string $template_path
     */
    public function __construct($toolname = '', $template_path = null)
    {
        if (!empty($toolname)) {
            if (isset($template_path)) {
                $path = $template_path.$toolname.'/';
            } else {
                $path = api_get_path(SYS_CODE_PATH).$toolname.'/';
            }
            if (is_dir($path)) {
                $this->tool_path = $path;
            } else {
                throw new Exception('View::__construct() $path directory does not exist '.$path);
            }
        }
    }

    /**
     * Set data sent from a controller
     * @param array data
     */
    public function set_data($data)
    {
        if (!is_array($data)) {
            throw new Exception('View::set_data() $data must to be an array, you have sent a'.gettype($data));
        }
        $this->data = $data;
    }

    /**
     * Set layout view sent from a controller
     * @param string layout view
     * @param string $layout
     */
    public function set_layout($layout)
    {
        $this->layout = $layout;
    }

    /**
     * Set template view sent from a controller
     * @param string template view
     * @param string $template
     */
    public function set_template($template)
    {
        $this->template = $template;
    }

    /**
     * Render data to the template and layout views
     */
    public function render()
    {
        $content = $this->render_template();
        $target = $this->tool_path.$this->layout.'.php';
        if (file_exists($target)) {
            require_once $target;
        } else {
            throw new Exception('View::render() invalid file path '.$target);
        }
    }

    /**
     * It's used into render method for rendering data in the template and layout views
     * @return  String  Rendered template (as HTML, most of the time)
     */
    private function render_template()
    {
        $target = $this->tool_path.$this->template.'.php';
        if (file_exists($target)) {
            ob_start();
            @extract($this->data, EXTR_OVERWRITE); //pass the $this->data array into local scope
            require_once $target;
            $content = ob_get_clean();
            return $content;
        } else {
            throw new Exception('View::render_template() invalid file path '.$target);
        }
    }
}