Get child category name and image - Magento 2.3

Question

I'm new to magento, i like to create own module for getting child category name and image in category page. Created Vendor name as "Sub" and modulename as "Categories"

app/code/Sub/Categories/View/frontend/templates/sub.phtml

<?php
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
$category = $objectManager->get('Magento\Framework\Registry')->registry('current_category');//get current category
$subcats = $category->getChildrenCategories();
$_helper = $this->helper('Magento\Catalog\Helper\Output');
?>
<ul>
    <?php
    foreach ($subcats as $subcat) {
        if ($subcat->getIsActive()) {
            $_category = $objectManager->create('Magento\Catalog\Model\Category')->load($subcat->getId());
            $_outputhelper = $this->helper('Magento\Catalog\Helper\Output');
            $subcaturl = $subcat->getUrl();

            $_imgHtml = '';
            if ($_imgUrl = $_category->getImageUrl()) {

                $_imgHtml = '<img src="' . $_imgUrl . '" />';
                $_imgHtml = $_outputhelper->categoryAttribute($_category, $_imgHtml, 'image');

                /* @escapeNotVerified */
                echo '<li><a href="' . $subcaturl . '" class="block-promo" title="' . $subcat->getName() . '">' . $_imgHtml . '<span style="background-color: rgba(255,255,255,0.9)" class="content bg-white"><strong>Place custom code here</strong><br><br><span class="action more button">Learn More</span></span></a></li>';
            }
        }
    } ?>
</ul>

app/code/Sub/Categories/Block/sub.php

<?php
namespace Sub\Categories\Block;

class Sub extends \Magento\Framework\View\Element\Template
{
    protected $_categoryHelper;
    protected $categoryFlatConfig;
    protected $topMenu;

    /**
     * @param \Magento\Framework\View\Element\Template\Context $context
     * @param \Magento\Catalog\Helper\Category $categoryHelper
     * @param array $data
     */
    public function __construct(
        \Magento\Framework\View\Element\Template\Context $context,
        \Magento\Catalog\Helper\Category $categoryHelper,
        \Magento\Catalog\Model\Indexer\Category\Flat\State $categoryFlatState,
        \Magento\Theme\Block\Html\Topmenu $topMenu
    )
    {
        $this->_categoryHelper = $categoryHelper;
        $this->categoryFlatConfig = $categoryFlatState;
        $this->topMenu = $topMenu;
        parent::__construct($context);
    }

    /**
     * Return categories helper
     */
    public function getCategoryHelper()
    {
        return $this->_categoryHelper;
    }

    /**
     * Return categories helper
     * getHtml($outermostClass = '', $childrenWrapClass = '', $limit = 0)
     * example getHtml('level-top', 'submenu', 0)
     */
    public function getHtml()
    {
        return $this->topMenu->getHtml();
    }

    /**
     * Retrieve current store categories
     *
     * @param bool|string $sorted
     * @param bool $asCollection
     * @param bool $toLoad
     * @return \Magento\Framework\Data\Tree\Node\Collection|\Magento\Catalog\Model\Resource\Category\Collection|array
     */
    public function getStoreCategories($sorted = false, $asCollection = false, $toLoad = true)
    {
        return $this->_categoryHelper->getStoreCategories($sorted, $asCollection, $toLoad);
    }

    /**
     * Retrieve child store categories
     *
     */
    public function getChildCategories($category)
    {
        if ($this->categoryFlatConfig->isFlatEnabled() && $category->getUseFlatResource()) {
            $subcategories = (array)$category->getChildrenNodes();
        } else {
            $subcategories = $category->getChildren();
        }
        return $subcategories;
    }
}

finally i create new block

{{block class="Sub\Categories\Block\sub" template="Sub_Categories::sub.phtml"}}

and assigned in widget.

Please let me know is any thing wrong in it. It does not change any thing in front-end.

Answer 1

Firstly, if you need this in custom phtml file then you need to include \Magento\Catalog\Block\Category\View block class file.

Or if you are overriding any category phtml template in your design then you can use below code:

---

<?php

$helper = $this->helper(Magento\Catalog\Helper\Category::class);
?>
<?php if ($_description = $block->getCurrentCategory()->getDescription()) :?>
    <div class="category-description">
        <?= $block->getCmsBlockHtml() ?>

        <?php 
            $categorys = $helper->getStoreCategories(false,false,true); 
            foreach($categorys as $category)
            {
                $subCategoriesOptions = [];
                $subCategories = (array) $category->getChildrenNodes();

                if ($subCategories)
                {
                    foreach ($subCategories as $value)
                    {
                        $subCategoriesOptions[$value->getId()] = $value->getName();
                    }
                }

            }
            //print_r($subCategoriesOptions);
            //exit;
        ?>

Answer 2

You need to do following things.

1. Overide Category List file into your extension.

app\code\Sub\Categories\view\frontend\layout\catalog_category_view.xml

<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" layout="2columns-left" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">

    <body>
        <referenceBlock name="category.products.list">
            <action method="setTemplate">
                <argument name="template" xsi:type="string">Sub_Categories::sub.phtml</argument>
            </action>
        </referenceBlock>
    </body>
</page>

2. Run the caching and commands and then check.