title: Add content to a tfoot in a table with Jquery
body: <p>I have this example table </p>
  
  <pre><code>&lt;table border="1" id="tabla"&gt;
   &lt;tr&gt;
    &lt;td&gt;row 1, cell 1&lt;/td&gt;
    &lt;td&gt;row 1, cell 2&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr&gt;
    &lt;td&gt;row 2, cell 1&lt;/td&gt;
    &lt;td&gt;row 2, cell 2&lt;/td&gt;
   &lt;/tr&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>I try to add content dynamically with Jquery with this</p>
  
  <pre><code>$("#tabla").find('tfoot').append($('&lt;td&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/td&gt;&lt;td&gt;a&lt;/td&gt;&lt;td&gt;b&lt;/td&gt;'));
  </code></pre>
  
  <p>But, don't works</p>
  
  <p>If a use firebug to inspect table, this have a tfoot but empty. ¿How to add dynamically content to a tfoot without added content previously?</p>