Overriding constructor in magento2

Question

I am not sure its happening with me because i am a newbie in magento2. Every time i try to override a constructor i end with an error. Tried to find out a lot but nothing helps. So at last decided to post here.

I want to override the execute method of Magento\Catalog\Controller\Category\View file. Basically category view page.

What i am doing is

namespace namespace\module\Controller\Magento\Catalog\Category;

class View extends \Magento\Catalog\Controller\Category\View
{
    protected $_coreRegistry = null;
    protected $_catalogSession;
    protected $_catalogDesign;
    protected $_storeManager;
    protected $categoryUrlPathGenerator;
    protected $resultPageFactory;
    protected $resultForwardFactory;
    private $layerResolver;
    protected $categoryRepository;

    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        \Magento\Catalog\Model\Design $catalogDesign,
        \Magento\Catalog\Model\Session $catalogSession,
        \Magento\Framework\Registry $coreRegistry,
        \Magento\Store\Model\StoreManagerInterface $storeManager,
        \Magento\CatalogUrlRewrite\Model\CategoryUrlPathGenerator $categoryUrlPathGenerator,
        PageFactory $resultPageFactory,
        \Magento\Framework\Controller\Result\ForwardFactory $resultForwardFactory,
        Resolver $layerResolver,
        CategoryRepositoryInterface $categoryRepository
    ) {
        $this->_storeManager = $storeManager;
        $this->_catalogDesign = $catalogDesign;
        $this->_catalogSession = $catalogSession;
        $this->_coreRegistry = $coreRegistry;
        $this->categoryUrlPathGenerator = $categoryUrlPathGenerator;
        $this->resultPageFactory = $resultPageFactory;
        $this->resultForwardFactory = $resultForwardFactory;
        $this->layerResolver = $layerResolver;
        $this->categoryRepository = $categoryRepository;
        parent::__construct($context,$storeManager,$catalogDesign,$coreRegistry,$categoryUrlPathGenerator,$resultPageFactory,$resultForwardFactory,$layerResolver,$categoryRepository);
    }

    public function execute()
    {
       // DO your code here.
    }

}

Now i am getting an error. Which says

Fatal error: Uncaught TypeError: Argument 7 passed to namespace\module\Controller\Magento\Catalog\Category\View::__construct() must be an instance of namespace\module\Controller\Magento\Catalog\Category\PageFactory, instance of Magento\Framework\View\Result\PageFactory given

I think this happens each time if its a factory class. Not sure though. Do you guys have any idea why it shows. Any help will be appreciated.

Answer 1

Try following way:

namespace Vendor\Module\Controller\Category;

use Magento\Catalog\Api\CategoryRepositoryInterface;
use Magento\Catalog\Model\Layer\Resolver;
use Magento\Framework\View\Result\PageFactory;

class View extends \Magento\Catalog\Controller\Category\View
{
    /**
     * @var \Magento\Customer\Model\CustomerFactory
     */
    protected $customerFactory;

    /**
     * Constructor
     *
     * @param \Magento\Framework\App\Action\Context $context
     * @param \Magento\Catalog\Model\Design $catalogDesign
     * @param \Magento\Catalog\Model\Session $catalogSession
     * @param \Magento\Framework\Registry $coreRegistry
     * @param \Magento\Store\Model\StoreManagerInterface $storeManager
     * @param \Magento\CatalogUrlRewrite\Model\CategoryUrlPathGenerator $categoryUrlPathGenerator
     * @param \Magento\Framework\View\Result\PageFactory $resultPageFactory
     * @param \Magento\Framework\Controller\Result\ForwardFactory $resultForwardFactory
     * @param Resolver $layerResolver
     * @param CategoryRepositoryInterface $categoryRepository
     * @param \Magento\Customer\Model\CustomerFactory $customerFactory
     * @SuppressWarnings(PHPMD.ExcessiveParameterList)
     */
    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        \Magento\Catalog\Model\Design $catalogDesign,
        \Magento\Catalog\Model\Session $catalogSession,
        \Magento\Framework\Registry $coreRegistry,
        \Magento\Store\Model\StoreManagerInterface $storeManager,
        \Magento\CatalogUrlRewrite\Model\CategoryUrlPathGenerator $categoryUrlPathGenerator,
        PageFactory $resultPageFactory,
        \Magento\Framework\Controller\Result\ForwardFactory $resultForwardFactory,
        Resolver $layerResolver,
        CategoryRepositoryInterface $categoryRepository,
        \Magento\Customer\Model\CustomerFactory $customerFactory
    ) {

        $this->customerFactory = $customerFactory;

        parent::__construct(
            $context,
            $catalogDesign,
            $catalogSession,
            $coreRegistry,
            $storeManager,
            $categoryUrlPathGenerator,
            $resultPageFactory,
            $resultForwardFactory,
            $layerResolver,
            $categoryRepository
        );
    }

    public function execute()
    {
        die('hello');
    }
}

Delete var/generation/*

N.B: Always try to use plugin, instead of overwrite whole class.