function search_api_facetapi_form_views_exposed_form_alter in Search API 7

Implements hook_form_FORM_ID_alter() for views_exposed_form().

Custom integration for facets. When a Views exposed filter is modified on a search results page, any facets which have been already selected will be removed. This (optionally) adds hidden fields for each facet so their values are retained.

File

contrib/search_api_facetapi/search_api_facetapi.module, line 548

Integrates the Search API with the Facet API.

Code

function search_api_facetapi_form_views_exposed_form_alter(array &$form, array &$form_state) {
  if (empty($form_state['view'])) {
    return;
  }
  $view = $form_state['view'];

  // Check if this is a Search API-based view and if the "Preserve facets"
  // option is enabled. ("search_api_multi" would be the exact base table name,
  // not just a prefix, but since it's just 16 characters long, we can still use
  // this check to make the condition less complex.)
  $base_table_prefix = substr($view->base_table, 0, 17);
  if (in_array($base_table_prefix, array(
    'search_api_index_',
    'search_api_multi',
  )) && _search_api_preserve_views_facets($view)) {

    // Get query parameters.
    $query_parameters = drupal_get_query_parameters();

    // Check if any facet query parameters are provided.
    if (!empty($query_parameters['f'])) {

      // Iterate through facet query parameters.
      foreach ($query_parameters['f'] as $key => $value) {

        // Add hidden form field for facet parameter.
        $form['f[' . $key . ']'] = array(
          '#type' => 'hidden',
          '#value' => $value,
          '#weight' => -1,
        );
      }
    }
  }
}