FAPI integration jQuery UI Multiselect

This can be used with FAPI fields already, basically all that's required is to add the same extra config that is added by jquery_ui_multiselect_field_widget_options_select_form_alter().

Module requirements remain, of course. I also found that adding height and width parameters is necessary otherwise the replaced fapi field won't show any of its contents.

Here's a before/after example for a select element:

  $form['tag_filter'] = array(
    '#title'         => t('Filter by tag(s)'),
    '#type'          => 'select',
    '#multiple'      => TRUE,
    '#options'       => $tags,
    '#default_value' => $default_value,
  );

And now with the extra config to make the multi-select work:

  $form['tag_filter'] = array(
    '#title'         => t('Filter by tag(s)'),
    '#type'          => 'select',
    '#multiple'      => TRUE,
    '#options'       => $tags,
    '#default_value' => $default_value,
    '#attached'      => array(
      'library' => array(
        array('jquery_ui_multiselect', 'jquery_ui_multiselect')
      ),
    ),
    '#attributes' => array(
      'class' => array(
        'jquery-ui-multiselect'
      ),
      'data-jquery-ui-multiselect' => drupal_json_encode(
        array(
          'sortable'                => TRUE,
          'dragToAdd'               => TRUE,
          'searchable'              => TRUE,
          'doubleClickable'         => TRUE,
          'includeRemoveAll'        => TRUE,
          'includeAddAll'           => TRUE,
          'selectedContainerOnLeft' => FALSE,
          'height'                  => 220,
          'width'                   => 440,
        )
      ),
    ),
  );