title: how to check the text box is dirty or not
body: <p>Hi following is my html code</p>
  
  <pre><code> &lt;th style="width:90px"&gt;
   &lt;span&gt;ID&lt;/span&gt;&lt;img class="serverRP_ajax-loader" src="loader_green_32.gif" /&gt;&lt;input type="text"  id="abc" ng-model="rpFilter.ResourcePlanID.value" /&gt;                           
                      &lt;/th&gt;
  </code></pre>
  
  <p>I want to enable loader_green_32.gif only when there is some value enter in abc textbox. $dirty is not possible because I am not using form tag</p>