Magento 2 Display Sub Category of parent?

Question

Magento 2 Display Sub Category of parent? I am trying to get subcategory using current category registry object but i don't know how to getChildrenCategories for parent.

Answer 1

My code to get the category list for the main category is:

public function __construct(
        Template\Context $context, 
        \Magento\Catalog\Model\Layer\Resolver $layerResolver, 
        \Magento\Framework\Registry $registry, 
        \Magento\Catalog\Helper\Category $categoryHelper, 
        \Magento\Catalog\Model\CategoryFactory  $categoryFactory,
        array $data = array()) 
    {
        parent::__construct($context, $layerResolver, $registry, $categoryHelper,$data);
        $this->_categoryFactory = $categoryFactory;
        $this->_collectionFactory = $collectionFactory;
     }

    public function getCategoryList()
    {
      $_category  = $this->getCurrentCategory();
      $collection = $this->_categoryFactory->create()->getCollection()->addAttributeToSelect('*')
              ->addAttributeToFilter('is_active', 1)
              ->setOrder('position', 'ASC')
              ->addIdFilter($_category->getChildren());
      return $collection;

    }

Answer 2

For reference you can start with core files See vendor/magento/module-catalog/Block/Navigation.php

getCurrentChildCategories() function:

$categories = $this->_catalogLayer->getCurrentCategory()->getChildrenCategories();

Where getCurrentCategory simply fetches current category from registry just like you did. So getChildrenCategories should work for you.

Also, more functions related to child/sub-categories are available in this file. vendor/magento/module-catalog/Model/Category.php . So if you get category object you can fetch sub-category data from it by using any of the functions defined in this file, as per your requirement.

Hope this helps!!

Answer 3

In your theme add the following to the appropriate container in your app/design/frontend/YourNamespace/YourTheme/layout/catalog_category_view.xml layout file.

<block class="Magento\Catalog\Block\Navigation"
           name="catalog.subnav"
           after="-"
           template="Magento_Catalog::category/category-subnav.phtml"/>

Then create a new file in app/design/frontend/YourNamespace/YourTheme/Magento_Catalog/templates/category/category-subnav.phtml and add the following.

<?php if (!$block->getCategory()) {
    return;
} ?>
<?php $_categories = $block->getCategory()->getParentCategory()->getChildrenCategories(); ?>
<?php $_count = is_array($_categories) ? count($_categories) : $_categories->count(); ?>
<?php if ($_count): ?>
    <div class="block subnav">
        <div class="content">
            <ol class="items">
                <?php foreach ($_categories as $_category): ?>
                    <?php if ($_category->getIsActive()): ?>
                        <li class="item">
                            <a href="<?php /* @escapeNotVerified */ echo $block->getCategoryUrl($_category) ?>"<?php if ($block->isCategoryActive($_category)): ?> class="current"<?php endif; ?>><?php echo $block->escapeHtml($_category->getName()) ?></a>
                        </li>
                    <?php endif; ?>
                <?php endforeach ?>
            </ol>
        </div>
    </div>
<?php endif; ?>

This should give you a list containing the current category and its siblings/child.

Answer 4

code for get subcategory from category id

class Test{

  public function __construct(
        \Magento\Catalog\Model\Category $categoryFactory
    )
    {
     $this->_categoryFactory = $categoryFactory;
    }
 $catId = 20;
 public function getsubCategories($catId){
    $cat = $this->_categoryFactory->load($catId);
    $subcats = $cat->getChildren();
    $subcategories = array();
    foreach(explode(',',$subcats) as $subCatid){
        $_subCategory = $this->_categoryFactory->load($subCatid);
        if($_subCategory->getIsActive()) {
            $subcategories[] = array('id'=>$_subCategory->getId(),'name'=>$_subCategory->getName()); 
        }
    }
    return $subcategories; 
}

Answer 5

Use below code to get all active child categories of a specific category.

Function getChildCategories($categoryId) gives all child categories. Where $categoryId - is parent category id

<?php
namespace YourModuleName\CategoryLink\Block;

use Magento\Framework\View\Element\Template;
use Magento\Framework\View\Element\Template\Context;
use Magento\Catalog\Model\CategoryFactory;


/**
 * Category link block
 */
class Link extends Template
{
    /**
     * @var Magento\Catalog\Model\CategoryFactory
     */
    protected $_categoryFactory;


    /**
     * 
     * @param Context $context
     * @param array $data
     */
    public function __construct(
        Context $context, 
        CategoryFactory $categoryFactory,
        array $data = []
    ) {
        parent::__construct($context, $data);
        $this->_categoryFactory = $categoryFactory;
      }

    /**
     * Get children categories 
     * 
     * @param $categoryId Parent category id
     * @return Magento\Catalog\Model\ResourceModel\Category\Collection
     */
    public function getChildCategories($categoryId)
    {

        $_category = $this->_categoryFactory->create();

        $category = $_category->load($categoryId);

        //Get category collection
        $collection = $category->getCollection()
                ->addIsActiveFilter()
                ->addOrderField('name')
                ->addIdFilter($category->getChildren());
        return $collection;
    }

} 

$category->getChildren() - This will gives all chid categories ids.