Source for file WPreviousStepButton.class.php

<?php
/**
 * @since Jul 20, 2005
 * @package polyphony.wizard.components
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: WPreviousStepButton.class.php,v 1.8 2007/09/19 14:04:51 adamfranco Exp $
 */ 
 
require_once(POLYPHONY."/main/library/Wizard/Components/WEventButton.class.php");
 
/**
 * This adds a "Previous" button to the wizard.
 * 
 * @since Jul 20, 2005
 * @package polyphony.wizard.components
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: WPreviousStepButton.class.php,v 1.8 2007/09/19 14:04:51 adamfranco Exp $
 */
class WPreviousStepButton extends WEventButton {
    var $_stepContainer;
 
    /**
     * Constructor
     * @param ref object $stepContainer A {@link WizardStepContainer} object.
     * @access public
     * @return void 
     */
    function WPreviousStepButton ($stepContainer) {
        $this->setLabel(_("Previous"));
        $this->_stepContainer =$stepContainer;
    }
 
    /**
     * Tells the wizard component to update itself - this may include getting
     * form post data or validation - whatever this particular component wants to
     * do every pageload.
     * @param string $fieldName The field name to use when outputting form data or
     *  similar parameters/information.
     * @access public
     * @return boolean - TRUE if everything is OK
     */
    function update ($fieldName) {
        parent::update($fieldName);
        if ($this->getAllValues()) {
            // advance the step!
            $this->_stepContainer->previousStep();
        }
    }
    
    /**
     * Answers true if this component will be enabled.
     * @access public
     * @return boolean 
     */
    function isEnabled () {
        return $this->_stepContainer->hasPrevious();
    }
 
}
 
?>