Send shipping email using an Observer

Question

I've managed to create an Observer to automatically create a shipment when an invoice is created.

The problem I have is with the final part of the code to send the email once the shipment has been created.

I wanted to ask if anyone can notice what is wrong with the $sendEmail call in my code.

Here's my Observer code for _saveShipment()

        protected function _saveShipment(Mage_Sales_Model_Order_Shipment $shipment, Mage_Sales_Model_Order $order, $customerEmailComments = '')
        {
            $shipment->getOrder()->setIsInProcess(true);
            Mage::log($shipment->debug(),Zend_Log::INFO,'shipment.log',true);
            $transactionSave = Mage::getModel('core/resource_transaction')
                ->addObject($shipment)
                ->addObject($order)
                ->save();

            $emailSentStatus = $shipment->getData('email_sent');
            if($emailSentStatus)
                Mage::log("Email has been sent",Zend_Log::INFO,'email.log',true);
            else
                Mage::log("IS FALSE",Zend_Log::INFO,'email.log',true);
//                Mage::log($customerEmailComments,Zend_Log::INFO,'email.log',true);
            if (!is_null($customerEmail) && !$emailSentStatus) {
                $shipment->setEmailSent(true);
                $shipment->sendEmail(true, $customerEmailComments);
            }

            return $this;
        }

Thanks for you time...

Answer 1

$customerEmail is not define try

.....
if (!is_null($shipment->getOrder()->getCustomerEmail()) && !$emailSentStatus) {
    $shipment->sendEmail(true, $customerEmailComments);
    $shipment->setEmailSent(true);
 }

Answer 2

Just change the position

$shipment->sendEmail(true, $customerEmailComments);
 $shipment->setEmailSent(true);

to

$shipment->setEmailSent(true);
$shipment->sendEmail(true, $customerEmailComments);

Also sales Shipment email sendEmail() depends on condition:Mage::helper('sales')->canSendNewShipmentEmail($storeId)

Check Shipment setting is enable from admin