Question

我想在顶部菜单中显示子类别的图像。我使用了它，但没有显示它的子类别图像。

创建您的模块在app/code/Vendor/NavigationMenu中创建一个文件夹，其中“供应商”是您模块的命名空间。

app / code / Vendor / NavigationMenu / etc / module.xml：

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Module/etc/module.xsd">
<module name="Vendor_NavigationMenu" setup_version="0.0.1"/></config>

现在注册模块：

<?php
/**
 * Registration file
 *
 * @category  Vendor
 * @package   Vendor\NavigationMenu
 * @author    Your Name <your@name.com>
 * @copyright 2017 Vendor
 * @license   http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */
\Magento\Framework\Component\ComponentRegistrar::register(
    \Magento\Framework\Component\ComponentRegistrar::MODULE,
    'Vendor_NavigationMenu',
    __DIR__
);

重写类Magento\Theme\Block\Html\TopMenu。创建di.xml来声明对调用_getHtml()方法的类的重写：

app / code / Vendor / NavigationMenu / etc / di.xml：

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\Theme\Block\Html\Topmenu" type="Vendor\NavigationMenu\Rewrite\Block\Html\Topmenu" />
</config>

现在，您可以创建将重写该方法的类。现在要注意以下几点：

我们将向该类添加一个自定义事件和一个观察者。这样，我们可以轻松地将所需的任何东西插入菜单。实际的图像添加将在观察者中完成。由于_getHtml() Magento本机功能不符合某些编码标准，因此我们不得不添加一些警告抑制措施

应用程序/代码/供应商/ NavigationMenu /重写/块/HTML/Topmenu.php：

<?php
/**
 * Vendor Project
 * Module Vendor/NavigationMenu
 *
 * @category  Vendor
 * @package   Vendor\NavigationMenu
 * @author    Your Name <your.name@email.com>
 * @copyright 2017 Vendor
 * @license   http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */
namespace Vendor\NavigationMenu\Rewrite\Block\Html;

use Magento\Framework\Data\Tree\Node;
use Magento\Framework\DataObject;
use Magento\Framework\View\Element\Template;

/**
 * Plugin NavigationMenu
 *
 * @author    Your Name <your.name@email.com>
 * @copyright 2017 Vendor
 */
class Topmenu extends \Magento\Theme\Block\Html\Topmenu
{
    /**
     * Recursively generates top menu html from data that is specified in $menuTree
     *
     * @param Node   $menuTree          menu tree
     * @param string $childrenWrapClass children wrap class
     * @param int    $limit             limit
     * @param array  $colBrakes         column brakes
     * @return string
     *
     * @SuppressWarnings(PHPMD)
     */
    protected function _getHtml(
        Node $menuTree,
        $childrenWrapClass,
        $limit,
        $colBrakes = []
    ) {
        $html = parent::_getHtml($menuTree, $childrenWrapClass, $limit, $colBrakes = []);

        $transportObject = new DataObject(['html' => $html, 'menu_tree' => $menuTree]);
        $this->_eventManager->dispatch(
            'vendor_topmenu_node_gethtml_after',
            ['menu' => $this->_menu, 'transport' => $transportObject]
        );

        $html = $transportObject->getHtml();

        return $html;
    }
}

创建由事件触发的观察者为此，我们需要创建events.xml配置文件并分配用于处理事件的类：

app / code / Vendor / NavigationMenu / etc / frontend / events.xml：

app /代码/供应商/NavigationMenu/Observer/AddContentToCategoryTopmenu.php：

<?php
/**
 * Topmenu catalog observer to add custom additional elements
 *
 * @category  Vendor
 * @package   Vendor\NavigationMenu
 * @author    Your Name <your.name@email.com>
 * @copyright 2017 Vendor
 * @license   http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */
namespace Vendor\NavigationMenu\Observer;

use Magento\Framework\Event\Observer;
use Magento\Framework\Event\ObserverInterface;
use Magento\Catalog\Api\CategoryRepositoryInterface;

/**
 * Class AddFirstCategoryImageToTopmenu
 * @package Vendor\NavigationMenu
 */
class AddContentToCategoryTopmenu implements ObserverInterface
{
    /**
     * @var CategoryRepositoryInterface $categoryRepository
     */
    protected $categoryRepository;

    /**
     * AddFirstCategoryImageToTopmenu constructor.
     *
     * @param CategoryRepositoryInterface $categoryRepository repository
     */
    public function __construct(
        CategoryRepositoryInterface $categoryRepository
    ) {
        $this->categoryRepository = $categoryRepository;
    }

    /**
     * @param Observer $observer Observer object
     */
    public function execute(Observer $observer)
    {
        $transport = $observer->getTransport();
        $html      = $transport->getHtml();
        $menuTree  = $transport->getMenuTree();

        $parentLevel = $menuTree->getLevel();
        $childLevel = $parentLevel === null ? 0 : $parentLevel + 1;

        $menuId = $menuTree->getId();

        if ($childLevel == 1 && $this->isCategory($menuId)) {
            $html .= '<li class="category_image" style=""><img src="'.$this->getCategoryImage($menuId).'"/></li>';
        }

        $transport->setHtml($html);
    }

    /**
     * Retrieves the category image for the corresponding child
     *
     * @param string $categoryId Category composed ID
     *
     * @return string
     */
    protected function getCategoryImage($categoryId)
    {
        $categoryIdElements = explode('-', $categoryId);
        $category           = $this->categoryRepository->get(end($categoryIdElements));
        $categoryName       = $category->getImageUrl();

        return $categoryName;
    }

    /**
     * Check if current menu element corresponds to a category
     *
     * @param string $menuId Menu element composed ID
     *
     * @return string
     */
    protected function isCategory($menuId)
    {
        $menuId = explode('-', $menuId);

        return 'category' == array_shift($menuId);
    }
}

在顶部菜单中显示子类别图片-Magento2

0 个答案: