diff --git a/views_nodejs/js/views_nodejs.js b/views_nodejs/js/views_nodejs.js
index 58c4709..80133a7 100644
--- a/views_nodejs/js/views_nodejs.js
+++ b/views_nodejs/js/views_nodejs.js
@@ -3,45 +3,46 @@
 /**
  * Drupal.Nodejs.callback on views update.
  */
-Drupal.Nodejs.callbacks.viewsNodejs = {
-  callback: function (message) {
-    if (Drupal.settings && Drupal.settings.viewsNodejs && Drupal.settings.viewsNodejs.views) {
-      $.each(Drupal.settings.viewsNodejs.views, function(i, view) {
-        var settings = view.settings;
+if (Drupal.Nodejs && Drupal.Nodejs.callbacks) {
+  Drupal.Nodejs.callbacks.viewsNodejs = {
+    callback: function (message) {
+      if (Drupal.settings && Drupal.settings.viewsNodejs && Drupal.settings.viewsNodejs.views) {
+        $.each(Drupal.settings.viewsNodejs.views, function (i, view) {
+          var settings = view.settings;
 
-        // Search in settings view which need update.
-        if (settings.view_name == message.view_id && settings.view_display_id == message.display_id) {
-          var selector = '.view-dom-id-' + settings.view_dom_id,
-              href = view.href,
-              viewData = {};
+          // Search in settings view which need update.
+          if (settings.view_name == message.view_id && settings.view_display_id == message.display_id) {
+            var selector = '.view-dom-id-' + settings.view_dom_id,
+                href = view.href,
+                viewData = {};
 
-          // Construct an object using the settings defaults and then overriding
-          // with data specific to the link.
-          $.extend(
-            viewData,
-            settings,
-            Drupal.Views.parseQueryString(href),
-            // Extract argument data from the URL.
-            Drupal.Views.parseViewArgs(href, settings.view_base_path)
-          );
+            // Construct an object using the settings defaults and then overriding
+            // with data specific to the link.
+            $.extend(
+                viewData,
+                settings,
+                Drupal.Views.parseQueryString(href),
+                // Extract argument data from the URL.
+                Drupal.Views.parseViewArgs(href, settings.view_base_path)
+            );
 
-          // For anchor tags, these will go to the target of the anchor rather
-          // than the usual location.
-          $.extend(viewData, Drupal.Views.parseViewArgs(href, settings.view_base_path));
+            // For anchor tags, these will go to the target of the anchor rather
+            // than the usual location.
+            $.extend(viewData, Drupal.Views.parseViewArgs(href, settings.view_base_path));
 
-          // Ajax settings for uping view.
-          var ajax_settings = {
-            url: Drupal.settings.viewsNodejs.ajax_path,
-            submit: viewData,
-            selector: selector
-          };
+            // Ajax settings for uping view.
+            var ajax_settings = {
+              url: Drupal.settings.viewsNodejs.ajax_path,
+              submit: viewData,
+              selector: selector
+            };
 
-          var ajax = new Drupal.ajax(false, false, ajax_settings);
-          ajax.eventResponse(ajax, {});
-        }
-      });
+            var ajax = new Drupal.ajax(false, false, ajax_settings);
+            ajax.eventResponse(ajax, {});
+          }
+        });
+      }
     }
-  }
-};
-
+  };
+}
 }(jQuery));