title: jQuery dynamic change with DOM updation
body: <p>I have inputs in a form like below. The number in the <code>id/name</code> is the sequence number. The sequence of inputs may be <strong>decreased/increased</strong> <strong>dynamically</strong> through jQuery. There is a default number of inputs in the form which will always be an Integer greater than 0.</p>
  
  <pre><code>&lt;select name="r_details-0-ch" id="id_r_details-0-ch"&gt;&lt;option value="" selected=""&gt;-&lt;/option&gt;
  &lt;input type="text" name="r_details-0-amt" step="0.01" id="id_r_details-0-amt"&gt;
  &lt;input type="text" name="r_details-0-nar" class="vTextField" maxlength="100" id="id_r_details-0-nar"&gt;
  
  
  &lt;select name="r_details-0-ch" id="id_r_details-0-ch"&gt;&lt;option value="" selected=""&gt;-&lt;/option&gt; 
  &lt;input type="text" name="r_details-1-amt" step="0.01" id="id_r_details-1-amt"&gt;
  &lt;input type="text" name="r_details-1-nar" class="vTextField" maxlength="100" id="id_r_details-1-nar"&gt;
  </code></pre>
  
  <p>I want to update <code>id_r_details-{x}-nar</code> via Ajax on change on of <code>id_r_details-{x}-amt</code> where <code>x</code> is a number representing the sequence.</p>
  
  <p>Just for information the form is rendered by <code>Django Admin inlines</code>.</p>
  
  <p>My questions:</p>
  
  <ol>
  <li>How to assign <code>.on('change', )</code> to <code>id_r_details-{x}-amt</code>.</li>
  <li>How to then update id_r_details-{x}-nar<code>with return value</code></li>
  <li>The value of the specific <code>id_r_details_{x}_ch</code> needs to be passed to the Ajax call.
  Ch is a select input with options, which I have omitted here for clarity.</li>
  </ol>
  
  <p>EDIT: Need to identify the sequence which fires .on('change, ). Then I think I can do all that needs to be done.</p>