Fixed Tab content lost on reload

src/myfasthtml/controls/TabsManager.py

@@ -114,12 +114,12 @@ class TabsManager(MultipleInstance):
     logger.debug(f"on_new_tab {label=}, {component=}, {auto_increment=}")
     if auto_increment:
       label = f"{label}_{self._get_tab_count()}"
-    tab_id = self.add_tab(label, component)
     component = component or VisNetwork(self._session, nodes=vis_nodes, edges=vis_edges)
+    tab_id = self.add_tab(label, component)
     return (
         self._mk_tabs_controller(),
         self._wrap_tab_content(self._mk_tab_content(tab_id, component)),
-        self._mk_tabs_header(True),
+        self._mk_tabs_header_wrapper(True),
     )
   
   def add_tab(self, label: str, component: Any, activate: bool = True) -> str:
@@ -258,7 +258,7 @@ class TabsManager(MultipleInstance):
       Script(f'updateTabs("{self._id}-controller");'),
     )
   
-  def _mk_tabs_header(self, oob=False):
+  def _mk_tabs_header_wrapper(self, oob=False):
     # Create visible tab buttons
     visible_tab_buttons = [
         self._mk_tab_button(self._state.tabs[tab_id])
@@ -318,14 +318,20 @@ class TabsManager(MultipleInstance):
     Returns:
         Div element containing the active tab content or empty container
     """
-    content = None
     
-    if self._state.active_tab and self._state.active_tab in self._state._tabs_content:
-      component = self._state._tabs_content[self._state.active_tab]
-      content = component
+    if self._state.active_tab:
+      active_tab = self._state.active_tab
+      if active_tab in self._state._tabs_content:
+        tab_content = self._state._tabs_content[active_tab]
+      else:
+        content = self._get_tab_content(active_tab)
+        tab_content = self._mk_tab_content(active_tab, content)
+        self._state._tabs_content[active_tab] = tab_content
+    else:
+      tab_content = self._mk_tab_content("", None)
     
     return Div(
-      self._mk_tab_content(self._state.active_tab, content),
+      tab_content,
       cls="mf-tab-content-wrapper",
       id=f"{self._id}-content-wrapper",
     )
@@ -374,7 +380,7 @@ class TabsManager(MultipleInstance):
     """
     return Div(
       self._mk_tabs_controller(),
-      self._mk_tabs_header(),
+      self._mk_tabs_header_wrapper(),
       self._mk_tab_content_wrapper(),
       cls="mf-tabs-manager",
       id=self._id,