title: Deprecated TransactionReceipt
body: <p>I am using this code for in-app purchases, took it from RaywernderLich's tutorial.    </p>
  
  <pre><code>// Encode the receiptData for the itms receipt verification POST request.
  NSString *jsonObjectString = [self encodeBase64:(uint8_t *)transaction.transactionReceipt.bytes
                                           length:transaction.transactionReceipt.length];
  </code></pre>
  
  <p>Now Xcode is saying</p>
  
  <blockquote>
    <p>'transactionReceipt' is deprecated: first deprecated in iOS 7.0</p>
  </blockquote>
  
  <p>How to fix it?</p>