Merge pull request #6582 from jdfreder/symmetric_state

Symmetric widget get/set_state

IPython/html/static/widgets/js/widget.js

@@ -69,7 +69,7 b' define(["widgets/js/manager",'
             var method = msg.content.data.method;
             switch (method) {
                 case 'update':
-                    this.apply_update(msg.content.data.state);
+                    this.set_state(msg.content.data.state);
                     break;
                 case 'custom':
                     this.trigger('msg:custom', msg.content.data.content);
@@ -80,7 +80,7 b' define(["widgets/js/manager",'
             }
         },
 
-        apply_update: function (state) {
+        set_state: function (state) {
             // Handle when a widget is updated via the python side.
             this.state_lock = state;
             try {

IPython/html/tests/widgets/widget.js

@@ -118,8 +118,8 b' casper.notebook_test(function () {'
         '    b = CInt(0, sync=True)\n' +
         '    c = CInt(0, sync=True)\n' +
         '    d = CInt(-1, sync=True)\n' + // See if it sends a full state.
-        '    def _handle_receive_state(self, sync_data):\n' +
-        '        widgets.Widget._handle_receive_state(self, sync_data)\n'+
+        '    def set_state(self, sync_data):\n' +
+        '        widgets.Widget.set_state(self, sync_data)\n'+
         '        self.d = len(sync_data)\n' +
         'multiset = MultiSetWidget()\n' +
         'display(multiset)\n' +

IPython/html/widgets/widget.py

@@ -208,6 +208,15 b' class Widget(LoggingConfigurable):'
             value = getattr(self, k)
             state[k] = f(value)
         return state
+
+    def set_state(self, sync_data):
+        """Called when a state is received from the front-end."""
+        for name in self.keys:
+            if name in sync_data:
+                json_value = sync_data[name]
+                from_json = self.trait_metadata(name, 'from_json', self._trait_from_json)
+                with self._lock_property(name, json_value):
+                    setattr(self, name, from_json(json_value))
     
     def send(self, content):
         """Sends a custom msg to the widget model in the front-end.
@@ -304,22 +313,13 b' class Widget(LoggingConfigurable):'
         # Handle backbone sync methods CREATE, PATCH, and UPDATE all in one.
         if method == 'backbone' and 'sync_data' in data:
             sync_data = data['sync_data']
-            self._handle_receive_state(sync_data) # handles all methods
+            self.set_state(sync_data) # handles all methods
 
         # Handle a custom msg from the front-end
         elif method == 'custom':
             if 'content' in data:
                 self._handle_custom_msg(data['content'])
 
-    def _handle_receive_state(self, sync_data):
-        """Called when a state is received from the front-end."""
-        for name in self.keys:
-            if name in sync_data:
-                json_value = sync_data[name]
-                from_json = self.trait_metadata(name, 'from_json', self._trait_from_json)
-                with self._lock_property(name, json_value):
-                    setattr(self, name, from_json(json_value))
-
     def _handle_custom_msg(self, content):
         """Called when a custom msg is received."""
         self._msg_callbacks(self, content)