Results: Add posibility to save multiple results for different solver.

src/View/MainWindow.py

@@ -596,7 +596,11 @@ class ApplicationWindow(QMainWindow, ListedSubWindow, WindowToolKit):
         if self._study is None:
             return None
 
-        return self._study.results
+        results = self._study.results
+        if self._last_solver._type in results:
+            return self._study.results[self._last_solver._type]
+
+        return None
 
     @last_results.setter
     def last_results(self, results):