Translator not working on helper class

Question

I try to translate a text in a function inside sales_helper_data with this code $this->__('TEXT') but it just returns the same input string.

I Also tried Mage::helper('sales')->__("TEXT"), Mage::helper('Admin')->__("TEXT"). Admin due to my module is admin module and created Mage_sales.csv in local/[lanfuage]

I Debugged the code and the Mage::app()->getTranslator()->getData() is an empty array. what's the problem?

Answer 1

I found the solution. I should add the translator file to module config.xml file

</adminhtml>
  <translate>
    <modules>
      <company_Sales>
        <files>
          <default>company_Sales.csv</default>
        </files>
      </company_Sales>
    </modules>
  </translate>
</adminhtml>