Added ability to title multicontainer pages before multicontainer display()

IPython/html/static/notebook/js/widgets/multicontainer.js

@@ -14,10 +14,14 b' require(["notebook/js/widget"], function(){'
             // Set tab titles
             var titles = this.model.get('_titles');
             for (var page_index in titles) {
-                var accordian_toggle = this.containers[page_index]
-                    .find('.accordion-heading')
-                    .find('.accordion-toggle');
-                accordian_toggle.html(titles[page_index]);
+
+                var accordian = this.containers[page_index]
+                if (accordian != undefined) {
+                    accordian
+                        .find('.accordion-heading')
+                        .find('.accordion-toggle')
+                        .html(titles[page_index]);
+                }
             }
 
             return IPython.WidgetView.prototype.update.call(this);
@@ -49,6 +53,7 b' require(["notebook/js/widget"], function(){'
             this.containers.push(accordion_group);
 
             accordion_inner.append(view.$el);
+            this.update();
         },
     });
 

IPython/html/widgets/widget.py

@@ -160,21 +160,22 b' class Widget(LoggingConfigurable):'
         key : unicode (optional)
             A single property's name to sync with the frontend.
         """
-        state = {}
-
-        # If a key is provided, just send the state of that key.
-        keys = []
-        if key is None:
-            keys.extend(self.keys)
-        else:
-            keys.append(key)
-        for key in self.keys:
-            try:
-                state[key] = getattr(self, key)
-            except Exception as e:
-                pass # Eat errors, nom nom nom
-        self.comm.send({"method": "update",
-                        "state": state})
+        if self.comm is not None:
+            state = {}
+
+            # If a key is provided, just send the state of that key.
+            keys = []
+            if key is None:
+                keys.extend(self.keys)
+            else:
+                keys.append(key)
+            for key in self.keys:
+                try:
+                    state[key] = getattr(self, key)
+                except Exception as e:
+                    pass # Eat errors, nom nom nom
+            self.comm.send({"method": "update",
+                            "state": state})
 
 
     def get_css(self, key, selector=""):