Empty field collection in hook_node_presave with entity_metadata_wrapper

Question

I have a node with a field type field_collection which has 2 items:

$node->field_field_collection['und'] = array(
  0 => array('value' => 1),
  1 => array('value' => 2),
);

on the save node drupal fire hook_node_presave:

/**
 * Implementation of hook_node_presave.
 */
function mymodule_node_presave($node) {
  $ewrapper = entity_metadata_wrapper('node', $node);
  $wrapper_counter = 0;
  $node_counter = 0;
  foreach ($ewrapper->field_field_collection->getIterator() as $delta => $fc_wrapper) {
    $wrapper_counter++;
  }
  foreach ($node->field_field_collection['und'] as $key => $value) {
    $node_counter++;
  }
}

after runing code

$wrapper_counter = 0;
$node_counter = 2;

what am I doing wrong?
I want to walk the field collection using entity_metadata_wrapper.

Drupal: 7.34
Entity API: 7.x-1.5
Field collection: 7.x-1.0-beta8

Answer 1

By this way as per this post:

/**
 * Implementation of hook_node_presave.
 */
function mymodule_node_presave($node) {
  if ($node -> type == 'my_type') {
    $field_field_collection = field_get_items('node', $node, 'field_field_collection');
    foreach ($field_field_collection as $key => $value) {
      $fc_wrapper = entity_metadata_wrapper('field_collection_item', $value['entity']);
      $fc_name = $fc_wrapper -> field_field_collection_name -> value();
      dsm($fc_name);
    }
  }
}

See: Understanding Field Collection Values and Entity metadata wrappers pages.