Drupal: Text Formatter Plaintext trimmed

modulename.module

<?php
function evt_news_field_formatter_info() {
  return array(
    'text_plain_trimmed' => array(
      'label' => t('Plain text (trimmed)'),
      'field types' => array('text', 'text_long', 'text_with_summary'),
      'settings' => array('trim_length' => 300),
  ));
}

function evt_news_field_formatter_settings_form($field, $instance, $view_mode, $form, &$form_state) {
  return text_field_formatter_settings_form($field, $instance, $view_mode, $form, $form_state);
}

/**
 * Implements hook_field_formatter_settings_summary().
 */
function evt_news_field_formatter_settings_summary($field, $instance, $view_mode) {
  return text_field_formatter_settings_summary($field, $instance, $view_mode);
}


/**
 * Implements hook_field_formatter_view().
 */
function evt_news_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display) {
  $element = array();

  switch ($display['type']) {
    case 'text_plain_trimmed':
      foreach ($items as $delta => $item) {
        $output = _text_sanitize($instance, $langcode, $item, 'value');
        $output = strip_tags($output);
        if ($display['type'] == 'text_plain_trimmed') {
          $output = text_summary($output, $instance['settings']['text_processing'] ? $item['format'] : NULL, $display['settings']['trim_length']);
        }
        $element[$delta] = array('#markup' => $output);
      }
      break;
  }

  return $element;
}