When re-applying the current sort, preserve sub-sorts

src/calibre/gui2/actions/sort.py

@@ -57,13 +57,7 @@ class SortByAction(InterfaceAction):
         lv.sort_by_named_field(sort_col, not order)
 
     def reapply_sort(self):
-        lv = self.gui.library_view
-        m = lv.model()
-        try:
-            sort_col, order = m.sorted_on
-        except TypeError:
-            sort_col, order = 'date', True
-        lv.sort_by_named_field(sort_col, order)
+        self.gui.library_view.resort()
 
     def location_selected(self, loc):
         enabled = loc == 'library'

src/calibre/gui2/library/views.py

@@ -600,6 +600,10 @@ class BooksView(QTableView):  # {{{
         except Exception:
             idx = -1
         self.set_sort_indicator(idx, ascending)
+
+    def resort(self):
+        with self.preserve_state(preserve_vpos=False, require_selected_ids=False):
+            self._model.resort(reset=True)
     # }}}
 
     # Ondevice column {{{