How to hide Fivestar rating field after first comment?

Question

The accepted answer on How to limit a user to one vote when using Fivestar? doesn't work for me, but the author hasn't provided a solution yet, so I felt this is worth a new question.

My goal is exactly the same as the one in the article mentioned above: I'd like to hide the Fivestar rating field (called field_stars) in the comment form when a user comments on a node on which he/she's already commented.

Is there another solution (for example with the Rules and Flags modules)?

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Edit: I already have a flag called Commented on my site and a rule that flags a node on behalf of the commentator when someone commented on it (which works perfectly). I'd really like to use it to fix this problem. I tried something, based on the information I found here:

function hiderating_form_alter(&$form, &$form_state, $form_id) {
  global $user;
  $flag = flag_get_flag('commented') or die('no "commented" flag defined');
  if ($form_id == "comment_node_stuff_form") {
   if ($form['#node']->uid == $user->uid OR $flag->is_flagged($form['#node']->uid, $user->uid)) { 
      unset($form['field_stars']);
    }
  }
}

Unfortunately, it doesn't change anything (I don't get any errors either).

Answer 1

In your node.tpl.php you should have the following code

hide($content['field_fivestar']);
print singlerating_print_rating($node->nid, $content['field_fivestar']);

I presume field_fivestar is the fivestar field you are using and not field_fivestar_rating

Answer 2

I nearly had the answer in my edit. The code should have been

function hiderating_form_alter(&$form, &$form_state, $form_id) {
  global $user;
  $flag = flag_get_flag('commented') or die('no "commented" flag defined');
  if ($form_id == "comment_node_stuff_form") {
   if ($form['#node']->uid == $user->uid OR $flag->is_flagged($form['#node']->nid, $user->uid)) { 
      unset($form['field_stars']);
    }
  }
}

So, the only thing that was wrong was $flag->is_flagged($form['#node']->uid. It should have been $flag->is_flagged($form['#node']->nid.

Many thanks to @jerdiggity on Stackoverflow!