Example for mapping MM elements to the wf_extendedBreadcrumb.

gistfile1.php

<?php if (!defined('TL_ROOT')) die('You cannot access this file directly!');

class XBreadCrumb extends Frontend
{

    /**
     * Constructor
     */
    public function __construct()
    {
        parent::__construct();
    }

    ////////////////////////////////////////////////////////////////////////////
    // Hooks
    ////////////////////////////////////////////////////////////////////////////

    /**
     * Add new items to the list.
     * Add a mapping for each site:
     *  $strKey   = Name of Filter attribute
     *  $strValue = Name of attribute for the displayed entry.
     */
    public function addItem($arrItems, $objBreadcrumb)
    {
        global $objPage;
        
        // News
        if ($objPage->id == 236)
        {
            $arrMapping = array('alias' => 'title');
            $arrItems   = $this->searchForMetaModelsModule($arrItems, $objBreadcrumb, true, $arrMapping);
        }
        // Press
        else if ($objPage->id == 249)
        {
            $arrMapping = array('alias' => 'title');
            $arrItems   = $this->searchForMetaModelsModule($arrItems, $objBreadcrumb, true, $arrMapping);
        }
        // Seminar
        else if ($objPage->id == 239)
        {
            $arrMapping = array('alias' => 'title');
            $arrItems   = $this->searchForMetaModelsModule($arrItems, $objBreadcrumb, true, $arrMapping);
        }

        return $arrItems;
    }

    ////////////////////////////////////////////////////////////////////////////
    // MM - Helper functions
    ////////////////////////////////////////////////////////////////////////////
    
    protected function searchForMetaModelsModule($arrItems, $objBreadcrumb, $blnLookup, $arrFieldMapping)
    {
        global $objPage;
        
        // Search all Conten elements.
        $arrArticle = $this->getChildRecords(array($objPage->id), 'tl_article');
        $arrContent = $this->getChildRecords($arrArticle, 'tl_content');
        
        // Search for a mm module.
        $objNewsModule = null;

        // Run each content element.
        foreach ($arrContent as $intContentId)
        {
            if ($this->getMetaModelsModule($intContentId) != null)
            {
                $objNewsModule = $this->getMetaModelsModule($intContentId);
                break;
            }
        }

        // Nothing found.
        if ($objNewsModule == null)
        {
            return $arrItems;
        }
        
        // Get data from metamodels.
        return $this->addItemsForModule($objBreadcrumb, $objNewsModule->id, $arrItems, true, $blnLookup, $arrFieldMapping);
    }
    
    /**
     * Search for a mm list module.
     * 
     * @param int $intContentId Id of the content element.
     * 
     * @return Database_Result Reuslt for the module or null if nothing was found.
     */
    protected function getMetaModelsModule($intContentId)
    {
        $objContentElement = Database::getInstance()
                ->prepare('SELECT * FROM tl_content WHERE id=?')
                ->execute($intContentId);

        if ($objContentElement->numRows == 0 || $objContentElement->type != 'module')
        {
            return null;
        }
        
        $objModule = Database::getInstance()
                ->prepare('SELECT * FROM tl_module WHERE id=?')
                ->execute($objContentElement->module);
        
        if ($objModule->numRows == 0 || $objModule->type != 'metamodel_list')
        {
            return null;
        }
        
        return $objModule;
    }

    /**
     * Try to get all current filter values for a speical module.
     *
     * @param int $intModuelId Id of the module
     * @param array $arrBreadcrumbItems List with all Items from the breadcrumb
     * @param type $blnRemoveLastEntrie Flag if the last elemnt should removed.
     * @param type $blnLookup Flag if a the system should lookup some other values.
     * @param type $strField Name for the attribute for lookup.
     *
     * @return array List with all new and old Items from the breadcrumb
     */
    protected function addItemsForModule($objBreadcrumb, $intModuelId, $arrBreadcrumbItems, $blnRemoveLastEntrie, $blnLookup, $arrFieldMapping)
    {
        $intMaxLentgh   = $objBreadcrumb->contextLength;
        $strPlaceholder = $objBreadcrumb->wf_extendedBreadcrumb_placeholder;
        
        // Get the module
        $objModule = $this->Database
                ->prepare('SELECT * FROM tl_module WHERE id=?')
                ->execute($intModuelId);


        // Check if we have some data.
        if ($objModule->numRows == 0 || $objModule->type != 'metamodel_list' || !empty($objModule->metamodel_filtering))
        {
            return $arrBreadcrumbItems;
        }

        // Get the filter id
        $intFilterRulesID = $objModule->metamodel_filtering;

        // Get the current filter and check if we have a value for it.
        $objFilterSettings = MetaModelFilterSettingsFactory::byId($intFilterRulesID);

        if ($objFilterSettings == null)
        {
            return $arrBreadcrumbItems;
        }

        // Get filter url params and mm.
        $arrFilterUrls = $objFilterSettings->getParameters();
        $arrAttributes = $objFilterSettings->getReferencedAttributes();
        $objMM         = $objFilterSettings->getMetaModel();

        $arrNavTitles = array();
       
        // Check each filter param.
        foreach ($arrFilterUrls as $strKey => $strValue)
        {
            // Get value.
            $strGetValue  = $this->Input->get($strValue);
            // Get values from the attribute
            $objAttribute = $objMM->getAttribute($arrAttributes[$strKey]);            
            $arrValues    = $objAttribute->getFilterOptions(null, false);
            
            // Add value to array.
            if ($blnLookup && !empty($arrFieldMapping) && array_key_exists($objAttribute->getColName(), $arrFieldMapping))
            {
                // Get return field from mapping.
                $strReturnField = $arrFieldMapping[$objAttribute->getColName()];                
                // Make a lookup.
                $arrNavTitles[] = $this->getValuesFromMM($objMM, $objAttribute, $strGetValue, $strReturnField);
            }
            else
            {
                // Use the value as it is.
                $arrNavTitles[] = $arrValues[$strGetValue];
            }
        }

        // Clear empty values.
        $arrNavTitles = array_filter($arrNavTitles);

        // Check if we have a entry.
        if (count($arrNavTitles) != 0)
        {
            if ($blnRemoveLastEntrie == true)
            {
                // Remove the last entry.
                array_pop($arrBreadcrumbItems);
            }
            else
            {
                // Remove the isActive from the last entry.
                $arrArrayKeys = array_keys($arrBreadcrumbItems);
                $intLastKey   = array_pop($arrArrayKeys);

                $arrBreadcrumbItems[$intLastKey]['isActive'] = false;
            }
            
            // Short the title if needed.
            $strFullTitle = $strTitle     = implode(' & ', $arrNavTitles);
            if (strlen($strTitle) > $intMaxLentgh)
            {
                $strTitle = String::getInstance()->substr($strTitle, (int) $intMaxLentgh, $strPlaceholder);
            }

            // Refresh the contextLength.
            $objBreadcrumb->contextLength = $intMaxLentgh - strlen($strTitle);

            // Add the new entry.
            $arrBreadcrumbItems[] = array
            (
                'isActive'  => TRUE,
                'href'      => '#',
                'title'     => $strTitle,
                'longtitle' => $strFullTitle,
                'class'     => ''
            );
        }

        return $arrBreadcrumbItems;
    }

    /**
     * 
     * @param IMetaModel $objMM
     * @param IMetaModelAttribute $objAttribute
     * @param string $strSearchValue
     * @param string $strReturnAttribute
     */
    protected function getValuesFromMM(&$objMM, &$objAttribute, $strSearchValue, $strReturnAttribute)
    {
        // Catch the item.
        $objFilter = $objMM->getEmptyFilter();
        $objFilter->addFilterRule(new MetaModelFilterRuleSearchAttribute($objAttribute, $strSearchValue));

        $objItems = $objMM->findByFilter($objFilter, $objAttribute->getColName(), 0, 1);

        // Check if we have  values.
        if ($objItems->getCount() == 0)
        {
            return $strSearchValue;
        }

        // Parse values.
        $objItem   = $objItems->getItem();
        $arrValues = $objItem->parseAttribute($strReturnAttribute);

        // Return values.
        if (isset($arrValues['text']))
        {
            return $arrValues['text'];
        }

        return $strSearchValue;
    }

}

?>