Fix re-render of layout

lumen/dashboard.py

@@ -816,8 +816,28 @@ def _navigate(self, event: param.parameterized.Event):
         pn.state.location.pathname = f'/{app}'
         pn.state.location.reload = True
 
-    def _set_loading(self, name: str = ''):
+    def _set_loading(self, name: str = '', reloading: bool = True):
         state.loading_msg.object = f'<b>Reloading {name}...</b>'
+        if reloading:
+            self._main.loading = True
+            return
+        if isinstance(self._layout, pn.GridBox):
+            items = [pn.pane.HTML(width=self._layout[i].width) # type: ignore
+                     for i in range(self._layout.ncols) if i < len(self._layout)]
+            index = int(min(self._layout.ncols, (len(self._layout)-1)) / 2)
+            if items:
+                items[index] = self._loading
+            else:
+                items = [self._loading]
+        elif isinstance(self._layout, pn.Tabs):
+            items = list(zip(self._layout._names, list(self._layout.objects))) # type: ignore
+            tab_name = items[self._layout.active][0]
+            if name and tab_name != name:
+                return
+            items[self._layout.active] = (tab_name, self._loading)
+        else:
+            items = [self._loading]
+        self._layout[:] = items
         self._main.loading = True
 
     def _open_modal(self, event: param.parameterized.Event):
@@ -875,7 +895,7 @@ def _render_filters(self):
 
     def _render_layouts(self, event: param.parameterized.Event | None = None):
         if event is not None:
-            self._set_loading(event.obj.title)
+            self._set_loading(event.obj.title, reloading=event.name == 'rerender')
         items = []
         for layout, spec in zip(self.layouts, state.spec.get('layouts', [])):
             if layout is None or isinstance(layout, Future):

lumen/layout.py

@@ -711,7 +711,7 @@ def _rerender(self, update_views: bool = True):
         if update_views:
             self._rerender_cards(cards)
             rerender = True
-        if set(cards) != set(self._cards):
+        if cards != self._cards:
             self._cards[:] = cards
             rerender = True
         if rerender: