Magento 2 – Should Object DOMDocument Be Created?

I am working on Magento 2.0.4 . I need to get collection of my custom table. For this I created the function getAreaCollection() in my block file but I got following error when I add constructor in block file.

Object DOMDocument should be created.

Here is my block file (\app\code\Techno\Area\Block\Area\index.php):-

namespace Techno\Area\Block\Area;

use Techno\Area\Block\BaseBlock;
use Techno\Area\Model\Area as AreaModel;
use Techno\Area\Model\Status;

class Index extends BaseBlock {

    protected $_areaFactory;
    protected $_area;
    protected $_areaCollectionFactory;
    protected $_areaHelper;

    public function __construct(
        Magento\Framework\View\Element\Template\Context $context 
        Techno\Area\Model\ResourceModel\Area\CollectionFactory $areaCollectionFactory, 
        Techno\Area\Model\AreaFactory $areaFactory, 
        AreaModel $area,
        Techno\Area\Helper\Data $areaHelper    
    ) {
        parent::__construct($context);
        $this->_areaFactory = $areaFactory;
        $this->_area = $area;
        $this->_areaCollectionFactory = $areaCollectionFactory;
        $this->_areaHelper = $areaHelper;
    }


    public function getAreaCollection() {
        $areaCollection = $this->_areaCollectionFactory->create()
                ->addFieldToFilter('status', Status::STATUS_ENABLED)
                ->setOrder('area_name', 'ASC');

        return $areaCollection;
    }

}

Can anyone guide me to make this working ?