I won't have a chance to look at this tonight, but just a comment that is probably irrelevant:

It's highly unusual to set #tree on a portion of a form rather than the whole form. #tree makes $form_state['values'] have its values in a hierarchical, rather than flat, arrangement, and it's not clear why you would want that. It's also rather dangerous to mess with #tree when you're form-altering, as it changes what will happen for other participants in the form.

One thing you should make sure to check: Is ahah.js being loaded on the page? Just check with firebug. If it's not, you may have to load it explicitly.

-Randy

On Wed, Dec 29, 2010 at 11:03 PM, <jeff@ayendesigns.com> wrote:
Next issue. My callback isn't being hit when I change the value in the master dropdown. I have the code below...simplified, albeit apparently wrong. Unlike the examples, the #ahah being added to the field does not result in any ahah references in jQuery.extend(Drupal.settings.


function test_menu() {
   $items = array();
   $items['test/dropdown/callback'] = array(
       'page callback' => 'test_do_callback',
       'type' => MENU_CALLBACK,
       'access_callback' => TRUE,
     );

   return $items;

}

function test_form_alter(&$form, &$form_state, $form_id) {
   if ($form_id == 'test_profile_node_form') {
       $form['field_two']['#prefix'] = '<div id="field-two-wrapper">';
       $form['field_two']['#suffix'] = '</div>';

       $form['field_master']['#ahah'] = array(
           'path' => 'test/dropdown/callback',
           'wrapper' => 'field-two-wrapper'
       );
       $form['field_master']['#tree'] = TRUE;
   }
}


function test_do_callback() {

// do stuff here

}




--
Randy Fay
Drupal Module and Site Development
randy@randyfay.com
+1  970.462.7450