title: How to dynamically inject custom info section into magento sales order view page (without modifying template)?
body: <p>I am working on a module that creates custom order attribute on sales order. I have achieved it like this:</p>
  
  <pre><code>&lt;?php
  
  // Init installer
  $installer = new Mage_Sales_Model_Mysql4_Setup;
  
  // Attribute Template
  $attribute  = array
  (
      'type'            =&gt; 'varchar',
      'backend_type'    =&gt; 'varchar',
      'frontend_input'  =&gt; 'varchar',
      'is_user_defined' =&gt; true,
      'label'           =&gt; '',
      'visible'         =&gt; true,
      'required'        =&gt; false,
      'user_defined'    =&gt; false,
      'searchable'      =&gt; false,
      'filterable'      =&gt; false,
      'comparable'      =&gt; false,
      'default'         =&gt; ''
  );
  
  // Sales Rep Attribute
  $sales_rep_attribute = $attribute;
  $sales_rep_attribute['label'] = 'Sales Rep';
  $installer-&gt;addAttribute('order', 'sales_rep', $sales_rep_attribute);
  
  // Delivery Date Attribute
  $delivery_date_attribute = $attribute;
  $delivery_date_attribute['label'] = 'Delivery Date';
  $installer-&gt;addAttribute('order', 'delivery_date', $delivery_date_attribute);
  
  // PPH Payment Type Attribute
  $pph_payment_type_attribute = $attribute;
  $pph_payment_type_attribute['label'] = 'PPH Payment Type';
  $installer-&gt;addAttribute('order', 'pph_payment_type', $pph_payment_type_attribute);
  
  // PPH Invoice Id Attribute
  $pph_invoice_id_attribute = $attribute;
  $pph_invoice_id_attribute['label'] = 'PPH Invoice Id';
  $installer-&gt;addAttribute('order', 'pph_invoice_id', $pph_invoice_id_attribute);
  
  // PPH Tx Id Attribute
  $pph_tx_id_attribute = $attribute;
  $pph_tx_id_attribute['label'] = 'PPH Tx Id';
  $installer-&gt;addAttribute('order', 'pph_tx_id', $pph_tx_id_attribute);
  
  // Finish installer
  $installer-&gt;endSetup();
  </code></pre>
  
  <p>After creating these attributes, I tried setting the <code>delivery date</code> for e.g. and it saves against the order and I am able to retrieve it.</p>
  
  <p>I would like to show these custom order attributes in the order view page in magento backend. I know you can do this by editing this file: <code>app/design/adminhtml/default/default/template/sales/order/view/info.phtml</code> and add this:</p>
  
  <pre><code>&lt;?php if($_order-&gt;getDeliveryDate()): ?&gt;
  &lt;tr&gt;
      &lt;td class=”label”&gt;&lt;label&gt;&lt;?php echo Mage::helper(‘sales’)-&gt;__(‘Delivery Date’) ?&gt;&lt;/label&gt;&lt;/td&gt;
      &lt;td class=”value”&gt;&lt;strong&gt;&lt;?php echo $_order-&gt;getDeliveryDate(); ?&gt;&lt;/strong&gt;&lt;/td&gt;
  &lt;/tr&gt;
  &lt;?php endif; ?&gt;
  </code></pre>
  
  <p>But this is manual labour. The order view template could also be over written by another module.</p>
  
  <p>Is it possible to make my module simply injects the additional order view section to the page without any manual edits? How should I go about doing this?</p>