disable view rendering in magento

Question

How to call the following two lines in magento's \app\code\core\Mage\Wishlist\Helper\Data.php file

$this->_helper->layout()->disableLayout();   
$this->_helper->viewRenderer->setNoRender();  

Actually there is a self created function getPdf() in Data.php which is used to generate pdf of wishlist items. It generates PDF with no error by using the statement

$pdf->save("hello.pdf");

But When I use the following statement

$pdfString = $pdf->render();
header("Content-Disposition: attachment; filename=myfile.pdf");
header("Content-type: application/x-pdf");
echo $pdfString;

It throws error: Adobe reader couldn't open myfile.pdf because it's not either a supported file type or because the file has been damaged. Now I need to call these two lines

$this->_helper->layout()->disableLayout();   
$this->_helper->viewRenderer->setNoRender(); 

in getPdf() function so that, it will not add html contents in pdf documents. Can you help me in this?

Answer 1

Before you echo $pdfString, add the following code to disable view rendering and the layout:

$vr = Zend_Controller_Action_HelperBroker::getStaticHelper('viewRenderer');
$vr->setNoRender(true);

$layout = Mage::getSingleton('core/layout');
$layout->disableLayout();

If the Mage::getSingleton() call doesn't return the correct layout object, you can also try $layout = $this->getLayout();