hook_field_formatter_view doesn't get called I'm kind of new to this formatter, widget system, so i hope you can help me out.
I'm trying to add a new widget to field type list_text, so i have added a info hook like this

function market_field_widget_info() {
  return array(
    'product_list' =&gt; array(
    'label' =&gt; t('Product List'),
    'field types' =&gt; array('list_text'),
    'settings' =&gt; array('size' =&gt; 40),
    'behaviors' =&gt; array(
      'multiple values' =&gt; FIELD_BEHAVIOR_DEFAULT,
    ),
  ),
);


And to my widget i have added a widget form hook like this

function market_field_widget_form(&amp;$form, &amp;$form_state, $field, $instance, $langcode, $items, $delta, $element) {

  if ($instance['widget']['type'] == 'product_list' &amp;&amp; arg(0) == 'node' ) {

  $node = node_load(arg(1));

  $options = array();
  foreach($node-&gt;field_products['und'] as $item ) {
    $entity = entity_load('field_collection_item', array($item['value']));
    $options[$item['value']] = $entity[$item['value']]-&gt;field_title['und'][0]['value'];
  }

  $element['product'] = array(
    '#type' =&gt; 'select',
    '#title' =&gt; t('Vare'),
    '#options' =&gt; $options,
  ); 
return $element;
}


And this works great, i get the information into the selector that i want, but when it is posted nothing is displayed, so i added a view to it

function market_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display) {
  $element = array();

  switch ($display['type']) {
    // This formatter simply outputs the field as text and with a color.
    case 'default_list':
      foreach ($items as $delta =&gt; $item) {
        $element[$delta]['#markup'] = "TEST";
      }
      break;
  }

  return $element;
}


But still nothing, am i missing something here? I have tried putting in a die, but its like the view hook is never called, hope you can help.

Best regards
In order for hook_field_formatter_view() to be called you also need to implement hook_field_formatter_info, to let the field system know about your custom formatter.

There's a good article called Creating new field formatters in Drupal 7 that has a step by step guide.