title: Joomla 3.0 Component JS error in backend
body: <p>I am developing a Joomla 3.0 component. As sample I downloaded the com_hello component from the Joomla documentation.</p>
  
  <p>The error I am occurring is that when I am checking the checkbox in the list of a view, I get an error message <code>TypeError: b is null</code>. This error occurred somewhere in the core.js.</p>
  
  <p>Normally in 2.5, if I used the <code>JHtml::_('grid.id',$i,$item-&gt;id);</code> code and had <code>&lt;input type="hidden" name="boxchecked" value="0" /&gt;</code> field in my form it worked fine.</p>
  
  <p>I also looked in some components of the Joomla core, but I didn't find something that was missing or some other error.</p>
  
  <p>Here is the code of the <code>default.php</code> of my view:</p>
  
  <pre><code>&lt;?php
  
  // NO DIRECT ACCESS TO THIS FILE
  defined('_JEXEC') or die('Restricted access');
  
  JHtml::_('behavior.tooltip');
  ?&gt;
  &lt;form action="&lt;?php echo JRoute::_('index.php?option=com_simplesuite'); ?&gt;" method="post" name="adminForm"&gt;
      &lt;table class="adminlist"&gt;
          &lt;thead&gt;
              &lt;tr&gt;
                  &lt;th&gt;ID&lt;/th&gt;
                  &lt;th&gt;&lt;input type="checkbox" name="checkall-toggle" title="&lt;?php echo JText::_('JGLOBAL_CHECK_ALL'); ?&gt;" value="" onclick="Joomla.checkAll(this);" /&gt;&lt;/th&gt;
                  &lt;th&gt;&lt;?php echo JText::_('COM_SIMPLESUITE_TAGCLOUD_ADMINISTRATOR_LIST_NAME'); ?&gt;&lt;/th&gt;
                  &lt;th&gt;&lt;?php echo JText::_('COM_SIMPLESUITE_TAGCLOUD_ADMINISTRATOR_LIST_TAGS'); ?&gt;&lt;/th&gt;
                  &lt;th&gt;&lt;?php echo JText::_('COM_SIMPLESUITE_TAGCLOUD_ADMINISTRATOR_LIST_ACTIONS'); ?&gt;&lt;/th&gt;
              &lt;/tr&gt;
          &lt;/thead&gt;
          &lt;tbody&gt;
              &lt;?php foreach ($this-&gt;items as $i =&gt; $item) : ?&gt;
              &lt;tr class="row&lt;?php echo $i%2; ?&gt;"&gt;
                  &lt;td&gt;&lt;?php echo $item-&gt;id; ?&gt;&lt;/td&gt;
                  &lt;td&gt;&lt;?php echo JHtml::_('grid.id',$i,$item-&gt;id); ?&gt;&lt;/td&gt;
                  &lt;td&gt;&lt;?php echo $item-&gt;name; ?&gt;&lt;/td&gt;
                  &lt;td&gt;&lt;?php echo ($item-&gt;tags) ? $item-&gt;tags : JText::_('COM_SIMPLESUITE_TAGCLOUD_ADMINISTRATOR_LIST_EMPTY'); ?&gt;&lt;/td&gt;
                  &lt;td&gt;&lt;a href="#"&gt;W&lt;/a&gt;&lt;a href="#"&gt;X&lt;/a&gt;&lt;/td&gt;
              &lt;/tr&gt;
              &lt;?php endforeach; ?&gt;
          &lt;/tbody&gt;
          &lt;tfoot&gt;
              &lt;tr&gt;
                  &lt;td colspan="4"&gt;&lt;?php echo $this-&gt;pagination-&gt;getListFooter(); ?&gt;&lt;/td&gt;
              &lt;/tr&gt;
          &lt;/tfoot&gt;
      &lt;/table&gt;
      &lt;div&gt;
          &lt;input type="hidden" name="task" value="" /&gt;
          &lt;input type="hidden" name="boxchecked" value="0" /&gt;
          &lt;?php echo JHtml::_('form.token'); ?&gt;
      &lt;/div&gt;
  &lt;/form&gt;
  </code></pre>