er/dart-core/Object-class.html">Object</a></span> <span class="parameter-name">error</span>, </span><span class="parameter" id="onError-param-stackTrace"><span class="type-annotation"><a href="https://api.flutter.dev/flutter/dart-core/StackTrace-class.html">StackTrace</a></span> <span class="parameter-name">stackTrace</span></span>)
    <span class="returntype parameter">&#8594; void</span>
  </span>
  

</dt>
<dd>
  This method is called when an error occurs when executing the request.
  

</dd>

        <