It used only within the class, and contains markup template schema.org/BreadcrumbList

@param string $label
@param array|string $url
@param int $key
@return string template microdata
973722
private static function getTemplate($label, $url, $key)
    {
        return '<li itemprop="itemListElement" itemscope itemtype="http://schema.org/ListItem">'
                . Html::a('<span itemprop="name">'.$label.'</span>', Url::to($url), ['itemprop'=>'item'])
                . '<meta itemprop="position" content="'.$key.'" /></li>';
    }
816666
public function prependItem($label, $url = '', $translateLabel = true)
    {
        $b = new BreadcrumbItem($label, $url, $translateLabel);
        array_unshift($this->items, $b);

        return $this;
    }
220497
public static function closeLink($label = '&times;', $htmlOptions = array())
    {
        $htmlOptions = ArrayHelper::defaultValue('href', '#', $htmlOptions);
        ArrayHelper::addValue('class', 'close', $htmlOptions);
        return \CHtml::openTag('a', $htmlOptions) . $label . \CHtml::closeTag('a');
    }
5873
public function createLink($label, $href = null)
    {
        $link = new Link($label, $href);
        $link->attributes->addAttributeClass('nav-link');

        return $this->createList($link);
    }
696699
public function hyperlink($label, $url, $options=array())
    {
        $defaults = array(
            'class' => 'btn btn-info'
        );
        $options = array_merge($defaults, $options);
        return parent::hyperlink($label, $url, $options);
    }
700071
public function key($name, $label = null)
    {
        $this->lastKey = $name;

        // Rest previous key's last rule
        $this->lastRule = null;

        if (!isset($this->options['rules'][$name])) {
            $this->options['rules'][$name] = [];
        }

        if (isset($label)) {
            $this->label($label);
        }

        return $this;
    }
642460
public function createBreadcrumb($label, $uri = null, $title = null, $description = null, $unshift = false)
    {
        //składanie breadcrumba
        $breadcrumb = ['label' => $label, 'uri' => $uri, 'title' => $title, 'description' => $description];
        //wstawienie przed
        if ($unshift) {
            array_unshift($this->_breadcrumbsData, $breadcrumb);
        } else {
            //wstawienie po
            $this->_breadcrumbsData[] = $breadcrumb;
        }
        //przebudowa breadcrumbów
        return $this->_buildBreadcrumbs();
    }
403007
protected function renderButton($label, $icon, $url)
	{
		$button = $this->button;
		$button['icon'] = $icon;
		$button['url'] = $url;
		$button['label'] = $label;
		$button['class'] = 'booster.widgets.TbButton';
		$widget = Yii::createComponent($button);
		$widget->init();
		$widget->run();
	}
24327
public function createItem($label = null, $href = null)
    {
        $link = new Link($label, $href);
        $link->attributes->addAttributeClass('dropdown-item');

        $this->childNodes->push($link);

        return $this->childNodes->last();
    }
510769
static function addUrlParam($url, $key, $val)
    {
        // Separate the anchor element from the URL if it exists.
        $urlParts = parse_url($url);
        if(isset($urlParts['fragment'])){
            $url = str_replace('#'.$urlParts['fragment'], '', $url);
        }

        $separator = (parse_url($url, PHP_URL_QUERY) == NULL) ? '?' : '&';
        $url .= $separator.$key.'='.$val;

        // Add the anchor back to the URL.
        if(isset($urlParts['fragment'])){
            $url .= '#'.$urlParts['fragment'];
        }

        return $url;
    }
176265
public function breadcrumbHasTheFollowingLinks(TableNode $table)
    {
        foreach ($table->getTable() as $breadcrumbItem) {
            $text = $breadcrumbItem[0];
            $url = $breadcrumbItem[1];

            // this is not a link (the current page)
            if ($url === 'null') {
                $query = sprintf(
                    '//ul[@id="wo-breadcrumbs"]/li/span[text()="%s"]',
                    $text
                );
            } else {
                $query = sprintf(
                    '//ul[@id="wo-breadcrumbs"]/li/a[@href="%s"]/span[text()="%s"]',
                    $url,
                    $text
                );
            }

            Assertion::assertCount(
                1, $this->getXpath()->findXpath($query)
            );
        }
    }
1059766
public function modifyBreadcrumb($index, $label, $uri = null, $title = null, $description = null)
    {
        //brak breadcrumbów
        if (!isset($this->_breadcrumbsData[$index])) {
            return $this;
        }
        //ustawianie label
        $this->_modifyBreadcrumbData($index, 'label', $label);
        //ustawianie uri
        $this->_modifyBreadcrumbData($index, 'uri', $uri);
        //ustawianie title
        $this->_modifyBreadcrumbData($index, 'title', $title);
        //ustawianie opisu
        $this->_modifyBreadcrumbData($index, 'description', $description);
        //przebudowa breadcrumba
        return $this->_buildBreadcrumbs();
    }
903174
protected function _appendToCrumb($str, $key = null) {
		if (empty($key)) {
			$key = end(array_keys($this->breadCrumbs));
		}

		$this->breadCrumbs["$key $str"] = $this->breadCrumbs[$key];
		unset($this->breadCrumbs[$key]);
	}
394223
public function addCalendarPage($label)
    {
        $page = $this->addPage($label, 'pr.calendar', 'calendar');
        $page->addAutofilterAction();
        $page->addExportAction();
        $page->addImportAction();
        $page->addAction(null, 'pr.calendar.simple-api', 'simple-api');

        return $page;
    }
740205
public function createLink($label, $href = null, $position = self::NAVBAR_LEFT)
    {
        if ( ! is_object($label) && isset($href)) {
            $label = new Link($label, $href);
        }

        switch ($position) {
            default:
            case self::NAVBAR_LEFT:
                $node = $this->left->createList($label);
                break;

            case self::NAVBAR_RIGHT:
                $node = $this->right->createList($label);
                break;
        }

        return $node;
    }
1077945
public static function add($label, $urlCode = null, $addedArgs = array())
  {
    self::$items[] = new BreadcrumbItem($label, $urlCode, $addedArgs);
  }
396078
protected function createPageLink($label, $page, $disabled, $active)
    {
        return array(
            'label' => $label,
            'url' => $this->createPageUrl($page),
            'disabled' => $disabled,
            'active' => $active,
        );
    }