';
+
+ drupal_add_tabledrag($table_id, 'order', 'sibling', $order_class);
+ }
+ else {
+ foreach (element_children($element) as $key) {
+ $output .= drupal_render($element[$key]);
+ }
+ }
+
+ return $output;
+}
+
+/**
+ * #after_build callback for field elements in a form.
+ *
+ * This stores the final location of the field within the form structure so
+ * that field_default_form_errors() can assign validation errors to the right
+ * form element.
+ *
+ * @see field_default_form_errors()
+ */
+function field_form_element_after_build($element, &$form_state) {
+ $parents = $element['#field_parents'];
+ $field_name = $element['#field_name'];
+ $langcode = $element['#language'];
+
+ $field_state = field_form_get_state($parents, $field_name, $langcode, $form_state);
+ $field_state['array_parents'] = $element['#array_parents'];
+ field_form_set_state($parents, $field_name, $langcode, $form_state, $field_state);
+
+ return $element;
+}
+
+/**
+ * Transfer field-level validation errors to widgets.
+ */
+function field_default_form_errors($entity_type, $entity, $field, $instance, $langcode, $items, $form, &$form_state) {
+ $field_state = field_form_get_state($form['#parents'], $field['field_name'], $langcode, $form_state);
+
+ if (!empty($field_state['errors'])) {
+ // Locate the correct element in the form.
+ $element = drupal_array_get_nested_value($form_state['complete form'], $field_state['array_parents']);
+ // Only set errors if the element is accessible.
+ if (!isset($element['#access']) || $element['#access']) {
+ $function = $instance['widget']['module'] . '_field_widget_error';
+ $function_exists = function_exists($function);
+
+ $multiple_widget = field_behaviors_widget('multiple values', $instance) != FIELD_BEHAVIOR_DEFAULT;
+ foreach ($field_state['errors'] as $delta => $delta_errors) {
+ // For multiple single-value widgets, pass errors by delta.
+ // For a multiple-value widget, pass all errors to the main widget.
+ $error_element = $multiple_widget ? $element : $element[$delta];
+ foreach ($delta_errors as $error) {
+ if ($function_exists) {
+ $function($error_element, $error, $form, $form_state);
+ }
+ else {
+ // Make sure that errors are reported (even incorrectly flagged) if
+ // the widget module fails to implement hook_field_widget_error().
+ form_error($error_element, $error['message']);
+ }
+ }
+ }
+ // Reinitialize the errors list for the next submit.
+ $field_state['errors'] = array();
+ field_form_set_state($form['#parents'], $field['field_name'], $langcode, $form_state, $field_state);
+ }
+ }
+}
+
+/**
+ * Submit handler for the "Add another item" button of a field form.
+ *
+ * This handler is run regardless of whether JS is enabled or not. It makes
+ * changes to the form state. If the button was clicked with JS disabled, then
+ * the page is reloaded with the complete rebuilt form. If the button was
+ * clicked with JS enabled, then ajax_form_callback() calls field_add_more_js()
+ * to return just the changed part of the form.
+ */
+function field_add_more_submit($form, &$form_state) {
+ $button = $form_state['triggering_element'];
+
+ // Go one level up in the form, to the widgets container.
+ $element = drupal_array_get_nested_value($form, array_slice($button['#array_parents'], 0, -1));
+ $field_name = $element['#field_name'];
+ $langcode = $element['#language'];
+ $parents = $element['#field_parents'];
+
+ // Increment the items count.
+ $field_state = field_form_get_state($parents, $field_name, $langcode, $form_state);
+ $field_state['items_count']++;
+ field_form_set_state($parents, $field_name, $langcode, $form_state, $field_state);
+
+ $form_state['rebuild'] = TRUE;
+}
+
+/**
+ * Ajax callback in response to a new empty widget being added to the form.
+ *
+ * This returns the new page content to replace the page content made obsolete
+ * by the form submission.
+ *
+ * @see field_add_more_submit()
+ */
+function field_add_more_js($form, $form_state) {
+ $button = $form_state['triggering_element'];
+
+ // Go one level up in the form, to the widgets container.
+ $element = drupal_array_get_nested_value($form, array_slice($button['#array_parents'], 0, -1));
+ $field_name = $element['#field_name'];
+ $langcode = $element['#language'];
+ $parents = $element['#field_parents'];
+
+ $field_state = field_form_get_state($parents, $field_name, $langcode, $form_state);
+
+ $field = $field_state['field'];
+ if ($field['cardinality'] != FIELD_CARDINALITY_UNLIMITED) {
+ return;
+ }
+
+ // Add a DIV around the delta receiving the Ajax effect.
+ $delta = $element['#max_delta'];
+ $element[$delta]['#prefix'] = '
';
+
+ return $element;
+}
+
+/**
+ * Retrieves processing information about a field from $form_state.
+ *
+ * @param $parents
+ * The array of #parents where the field lives in the form.
+ * @param $field_name
+ * The field name.
+ * @param $langcode
+ * The language in which the field values are entered.
+ * @param $form_state
+ * The form state.
+ *
+ * @return
+ * An array with the following key/data pairs:
+ * - field: the field definition array,
+ * - instance: the field instance definition array,
+ * - items_count: the number of widgets to display for the field,
+ * - array_parents: the location of the field's widgets within the $form
+ * structure. This entry is populated at '#after_build' time.
+ * - errors: the array of field validation errors reported on the field. This
+ * entry is populated at field_attach_form_validate() time.
+ *
+ * @see field_form_set_state()
+ */
+function field_form_get_state($parents, $field_name, $langcode, &$form_state) {
+ $form_state_parents = _field_form_state_parents($parents, $field_name, $langcode);
+ return drupal_array_get_nested_value($form_state, $form_state_parents);
+}
+
+/**
+ * Stores processing information about a field in $form_state.
+ *
+ * @param $parents
+ * The array of #parents where the field lives in the form.
+ * @param $field_name
+ * The field name.
+ * @param $langcode
+ * The language in which the field values are entered.
+ * @param $form_state
+ * The form state.
+ * @param $field_state
+ * The array of data to store. See field_form_get_state() for the structure
+ * and content of the array.
+ *
+ * @see field_form_get_state()
+ */
+function field_form_set_state($parents, $field_name, $langcode, &$form_state, $field_state) {
+ $form_state_parents = _field_form_state_parents($parents, $field_name, $langcode);
+ drupal_array_set_nested_value($form_state, $form_state_parents, $field_state);
+}
+
+/**
+ * Returns the location of processing information within $form_state.
+ */
+function _field_form_state_parents($parents, $field_name, $langcode) {
+ // To ensure backwards compatibility on regular entity forms for widgets that
+ // still access $form_state['field'][$field_name] directly,
+ // - top-level fields (empty $parents) are placed directly under
+ // $form_state['fields'][$field_name].
+ // - Other fields are placed under
+ // $form_state['field']['#parents'][...$parents...]['#fields'][$field_name]
+ // to avoid clashes between field names and $parents parts.
+ // @todo Remove backwards compatibility in Drupal 8, and use a unique
+ // $form_state['field'][...$parents...]['#fields'][$field_name] structure.
+ if (!empty($parents)) {
+ $form_state_parents = array_merge(array('#parents'), $parents, array('#fields'));
+ }
+ else {
+ $form_state_parents = array();
+ }
+ $form_state_parents = array_merge(array('field'), $form_state_parents, array($field_name, $langcode));
+
+ return $form_state_parents;
+}
+
+/**
+ * Retrieves the field definition for a widget's helper callbacks.
+ *
+ * Widgets helper element callbacks (such as #process, #element_validate,
+ * #value_callback, ...) should use field_widget_field() and
+ * field_widget_instance() instead of field_info_field() and
+ * field_info_instance() when they need to access field or instance properties.
+ * See hook_field_widget_form() for more details.
+ *
+ * @param $element
+ * The structured array for the widget.
+ * @param $form_state
+ * The form state.
+ *
+ * @return
+ * The $field definition array for the current widget.
+ *
+ * @see field_widget_instance()
+ * @see hook_field_widget_form()
+ */
+function field_widget_field($element, $form_state) {
+ $field_state = field_form_get_state($element['#field_parents'], $element['#field_name'], $element['#language'], $form_state);
+ return $field_state['field'];
+}
+
+/**
+ * Retrieves the instance definition array for a widget's helper callbacks.
+ *
+ * Widgets helper element callbacks (such as #process, #element_validate,
+ * #value_callback, ...) should use field_widget_field() and
+ * field_widget_instance() instead of field_info_field() and
+ * field_info_instance() when they need to access field or instance properties.
+ * See hook_field_widget_form() for more details.
+ *
+ * @param $element
+ * The structured array for the widget.
+ * @param $form_state
+ * The form state.
+ *
+ * @return
+ * The $instance definition array for the current widget.
+ *
+ * @see field_widget_field()
+ * @see hook_field_widget_form()
+ */
+function field_widget_instance($element, $form_state) {
+ $field_state = field_form_get_state($element['#field_parents'], $element['#field_name'], $element['#language'], $form_state);
+ return $field_state['instance'];
+}