Hey Guys!
I'm working on a project where I need to load data via AJAX-Request. To do this I use a XML-File. Everything just works fine until I try to get the values of an "activity".

THE XML-FILE

<item>
  <id>19</id>
  <date>2013-01-23</date>
  <department>Some text...</department>
  <text>Some text...</text>
  <status>1</status>
  <user_id>1</user_id>

  <activities>
    <count>1</count>

    <activity>
      <a_id>20</a_id>
      <a_item_id>19</a_item_id>
      <a_user_id>1</a_user_id>
      <a_time>3.0</a_time>
      <a_text>Some text...</a_text>
    </activity>
  </activities>
</item>

My approach was the following:

var a_id = xmlDoc.getElementsByTagName("activity")[0].childNodes[0].nodeValue;

But this returns nothing.

Any idea how to "navigate" to "a_id"?