From 7cd59c6bc49b9a8608eb07304b265a59fe51e63f Mon Sep 17 00:00:00 2001
From: Angie Byron <webchick@24967.no-reply.drupal.org>
Date: Fri, 14 Aug 2009 05:16:26 +0000
Subject: #548630 by bjaspan: Document hook_field_is_empty().

---
 modules/field/field.api.php | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

(limited to 'modules/field/field.api.php')

diff --git a/modules/field/field.api.php b/modules/field/field.api.php
index 6f40c2009..39618ea08 100644
--- a/modules/field/field.api.php
+++ b/modules/field/field.api.php
@@ -125,6 +125,7 @@ function hook_fieldable_info_alter(&$info) {
  * @see hook_field_delete().
  * @see hook_field_delete_revision().
  * @see hook_field_sanitize().
+ * @see hook_field_is_empty().
  *
  * The Field Types API also defines two kinds of pluggable handlers: widgets
  * and formatters, which specify how the field appears in edit forms and in
@@ -518,6 +519,24 @@ function hook_field_delete_revision($obj_type, $object, $field, $instance, $item
 function hook_field_prepare_translation($obj_type, $object, $field, $instance, $items) {
 }
 
+/**
+ * Define what constitutes an empty item for a field type.
+ *
+ * @param $item
+ *   An item that may or may not be empty.
+ * @param $field
+ *   The field to which $item belongs.
+ * @return
+ *   TRUE if $field's type considers $item not to contain any data;
+ *   FALSE otherwise.
+ */
+function hook_field_is_empty($item, $field) {
+  if (empty($item['value']) && (string)$item['value'] !== '0') {
+    return TRUE;
+  }
+  return FALSE;
+}
+
 /**
  * Expose Field API widget types.
  *
-- 
cgit v1.2.3