Do not process events related to fake Template root

panel/io/state.py

@@ -42,6 +42,9 @@ class _state(param.Parameterized):
     # An index of all currently active views
     _views = {}
 
+    # For templates to keep reference to their main root
+    _fake_roots = []
+
     # An index of all currently active servers
     _servers = {}
 

panel/layout.py

@@ -19,6 +19,7 @@
 from bokeh.models.widgets import Tabs as BkTabs, Panel as BkPanel
 
 from .io.model import hold
+from .io.state import state
 from .util import param_name, param_reprs
 from .viewable import Layoutable, Reactive
 
@@ -190,6 +191,8 @@ def _process_param_change(self, params):
         return super(ListPanel, self)._process_param_change(params)
 
     def _cleanup(self, root):
+        if root.ref['id'] in state._fake_roots:
+            state._fake_roots.remove(root.ref['id'])
         super(ListPanel, self)._cleanup(root)
         for p in self.objects:
             p._cleanup(root)
@@ -652,14 +655,17 @@ def _process_close(self, ref, attr, old, new):
         return old, new
 
     def _comm_change(self, doc, ref, attr, old, new):
-        if attr in self._changing:
-            self._changing.remove(attr)
+        if attr in self._changing.get(ref, []):
+            self._changing[ref].remove(attr)
             return
         if attr == 'tabs':
             old, new = self._process_close(ref, attr, old, new)
         super(Tabs, self)._comm_change(doc, ref, attr, old, new)
 
     def _server_change(self, doc, ref, attr, old, new):
+        if attr in self._changing.get(ref, []):
+            self._changing[ref].remove(attr)
+            return
         if attr == 'tabs':
             old, new = self._process_close(ref, attr, old, new)
         super(Tabs, self)._server_change(doc, ref, attr, old, new)

panel/pane/base.py

@@ -179,6 +179,8 @@ def _update_object(self, ref, doc, root, parent, comm):
 
     def _update_pane(self, *events):
         for ref, (_, parent) in self._models.items():
+            if ref not in state._views or ref in state._fake_roots:
+                continue
             viewable, root, doc, comm = state._views[ref]
             if comm or state._unblocked(doc):
                 with unlocked():

panel/template.py

@@ -128,6 +128,7 @@ def _init_doc(self, doc=None, comm=None, title=None, notebook=False):
             model.name = name
             model.tags = tags
             add_to_doc(model, doc, hold=bool(comm))
+        state._fake_roots.append(ref)
         state._views[ref] = (col, preprocess_root, doc, comm)
 
         col._preprocess(preprocess_root)

panel/viewable.py

@@ -469,16 +469,16 @@ def _repr_mimebundle_(self, include=None, exclude=None):
         return render_mimebundle(model, doc, comm, manager)
 
     def _comm_change(self, doc, ref, attr, old, new):
-        if attr in self._changing:
-            self._changing.remove(attr)
+        if attr in self._changing.get(ref, []):
+            self._changing[ref].remove(attr)
             return
 
         with hold(doc):
             self._process_events({attr: new})
 
     def _server_change(self, doc, ref, attr, old, new):
-        if attr in self._changing:
-            self._changing.remove(attr)
+        if attr in self._changing.get(ref, []):
+            self._changing[ref].remove(attr)
             return
 
         state._locks.clear()
@@ -735,21 +735,21 @@ def __init__(self, **params):
         self._callbacks = []
         self._links = []
         self._link_params()
-        self._changing = []
+        self._changing = {}
 
     #----------------------------------------------------------------
     # Callback API
     #----------------------------------------------------------------
 
     def _update_model(self, events, msg, root, model, doc, comm):
-        self._changing = [
+        self._changing[root.ref['id']] = [
             attr for attr, value in msg.items()
             if not model.lookup(attr).property.matches(getattr(model, attr), value)
         ]
         try:
             model.update(**msg)
         finally:
-            self._changing = []
+            del self._changing[root.ref['id']]
 
     def param_change(self, *events):
         msgs = []
@@ -764,7 +764,7 @@ def param_change(self, *events):
             return
 
         for ref, (model, parent) in self._models.items():
-            if ref not in state._views:
+            if ref not in state._views or ref in state._fake_roots:
                 continue
             viewable, root, doc, comm = state._views[ref]
             if comm or not doc.session_context or state._unblocked(doc):

panel/widgets/base.py

@@ -68,6 +68,8 @@ def _manual_update(self, events, model, doc, root, parent, comm):
 
     def _update_widget(self, *events):
         for ref, (model, parent) in self._models.items():
+            if ref not in state._views or ref in state._fake_roots:
+                continue
             viewable, root, doc, comm = state._views[ref]
             if comm or state._unblocked(doc):
                 with unlocked():