MainWindow: Put results menu in model action list.

src/View/MainWindow.py

@@ -104,7 +104,8 @@ define_model_action = [
     "action_menu_edit_friction", "action_menu_edit_lateral_contribution",
     "action_menu_run_solver", "action_menu_sediment_layers",
     "action_menu_edit_reach_sediment_layers", "action_menu_edit_reservoirs",
-    "action_menu_edit_hydraulic_structures"
+    "action_menu_edit_hydraulic_structures",
+    "action_menu_results_last", "action_open_results_from_file",
 ]
 
 action = (
@@ -371,7 +372,8 @@ class ApplicationWindow(QMainWindow, ListedSubWindow, WindowToolKit):
 
             if solver.name == self.conf.last_solver_name:
                 self._last_solver = solver
-                self.enable_actions("action_menu_results_last", True)
+                if self._study is not None:
+                    self.enable_actions("action_menu_results_last", True)
                 return
 
         # Last solver note found, use default-mage if exists