Display a list of type group

I have read the tutorial, and the API, looked through the code examples. But when it came down to implementation, it didn't work as i thought it would.

I am trying to avoid using the Views module for now, just for learning purposes.

function mymodule_menu() {
  $items['groups'] = array(
    'title' => t('Groups list'),
    'page callback' => 'mymodule_groups_overview',
    'access callback' => TRUE
  );

  return $items;
}

function mymodule_groups_overview() {
  $build = array();

  $query = db_select('og', 'og')->extend('PagerDefault');
  $query->fields('og', array('gid'));

  $result = $query
    ->limit(10)
    ->orderBy('og.gid')
    ->execute();    

  if ($result) {
    $gids = $result->fetchCol();
    $entities = og_load_multiple($gids);    
    $build = entity_view('group', $entities, 'teaser');
  }

  return $build;
}

The problem is that entity_view(..) returns nothing, and og_load_multiple(..) returns an array of entities, but there is no content and no fields.

If this worked, I would probably override the controller, 开发者_运维技巧declare it in mymodule_entity_info_alter(..), and added a new view mode 'list'.

Can anyone please share a working code for displaying a list of entities with a pager?

P.S. I took the groups for example but i dont mind any other type of entities.

---

Just a thought, what happens when you use 'full' instead of teaser in the call to entity_view? Have you checked that the display mode for teasers for type 'group' actually has some fields to display in it?