Fallback to ipywidgets

notebook/notebookapp.py

@@ -239,16 +239,21 @@ class NotebookWebApplication(web.Application):
         handlers.extend(load_handlers('services.security.handlers'))
         
         # BEGIN HARDCODED WIDGETS HACK
+        widgets = None
         try:
             widgets = __import__('jupyter-js-widgets-nbextension')
+        except:
+            try:
+                widgets = __import__('ipywidgets')
+            except:
+                app_log.warning('jupyter-js-widgets-nbextension package not installed.  Widgets are unavailable.')
+        if widgets is not None:
             handlers.append(
                 (r"/nbextensions/widgets/(.*)", FileFindHandler, {
                     'path': widgets.find_static_assets(),
                     'no_cache_paths': ['/'], # don't cache anything in nbextensions
                 }),
             )
-        except:
-            app_log.warning('jupyter-js-widgets-nbextension package not installed.  Widgets are unavailable.')
         # END HARDCODED WIDGETS HACK
         
         handlers.append(

notebook/static/notebook/js/main.js

@@ -55,8 +55,12 @@ require([
     "use strict";
 
     // BEGIN HARDCODED WIDGETS HACK
+    // Try to load the new extension
     utils.load_extension('widgets/extension').catch(function () {
-        console.warn('ipywidgets package not installed.  Widgets are not available.');
+    // Fallback to the ipywidgets extension
+        utils.load_extension('widgets/notebook/js/extension').catch(function () {
+            console.warn('ipywidgets package not installed.  Widgets are not available.');
+        });
     });
     // END HARDCODED WIDGETS HACK