Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

namespace core\progress;

defined('MOODLE_INTERNAL') || die();

/**

 * Progress handler that uses a standard Moodle progress bar to display

 * progress. Same as \core\progress\display, but the bar does not

 * appear until a certain time has elapsed, and disappears automatically

 * after it finishes.

 *

 * The bar can be re-used, i.e. if you end all sections it will disappear,

 * but if you start all sections, a new bar will be output.

 *

 * @package core_progress

 * @copyright 2013 The Open University

 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class display_if_slow extends display {

    /**

     * @var int Waits this many seconds before displaying progress bar

     */

    const DEFAULT_DISPLAY_DELAY = 5;

    /**

     * @var int Number in the next id to use

     */

    private static $nextid = 1;

    /**

     * @var string HTML id for containing div

     */

    protected $id;

    /**

     * @var string Text to display in heading if bar appears

     */

    protected $heading;

    /**

     * @var int Time at which the progress bar should display (if it isn't yet)

     */

    protected $starttime;

    /**

     * Constructs the progress reporter. This will not output HTML just yet,

     * until the required delay time expires.

     *

     * @param string $heading Text to display above bar (if it appears); '' for none (default)

     * @param int $delay Delay time (default 5 seconds)

     */

    public function __construct($heading = '', $delay = self::DEFAULT_DISPLAY_DELAY) {

        // Set start time based on delay.

        $this->starttime = time() + $delay;

        $this->heading = $heading;

        parent::__construct(false);

    }

    /**

     * Starts displaying the progress bar, with optional heading and a special

     * div so it can be hidden later.

     *

     * @see \core\progress\display::start_html()

     */

    public function start_html() {

        global $OUTPUT;

        $this->id = 'core_progress_display_if_slow' . self::$nextid;

        self::$nextid++;

        // Containing div includes a CSS class so that it can be themed if required,

        // and an id so it can be automatically hidden at end.

        echo \html_writer::start_div('core_progress_display_if_slow',

                array('id' => $this->id));

        // Display optional heading.

        if ($this->heading !== '') {

            echo $OUTPUT->heading($this->heading, 3);

        }

        // Use base class to display progress bar.

        parent::start_html();

    }

    /**

     * When progress is updated, after a certain time, starts actually displaying

     * the progress bar.

     *

     * @see \core\progress\base::update_progress()

     */

    public function update_progress() {

        // If we haven't started yet, consider starting.

        if ($this->starttime) {

            if (time() > $this->starttime) {

                $this->starttime = 0;

            } else {

                // Do nothing until start time.

                return;

            }

        }

        // We have started, so handle as default.

        parent::update_progress();

    }

    /**

     * Finishes parent display then closes div and hides it.

     *

     * @see \core\progress\display::end_html()

     */

    public function end_html() {

        parent::end_html();

        echo \html_writer::end_div();

        echo \html_writer::script('document.getElementById("' . $this->id .

                '").style.display = "none"');

    }

}