don't hide gtkmm interfaces! (gtkmm doc)

src/window.cc

@@ -683,7 +683,7 @@ bool Window::on_delete_event (GdkEventAny *event) {
   return true;
 }
 
-void Window::hide() {
+void Window::on_hide() {
   auto size=notebook.size();
   for(int c=0;c<size;c++) {
     if(!notebook.close_current_page())

src/window.h

@@ -29,7 +29,7 @@ private:
   void configure();
   void set_menu_actions();
   void activate_menu_items(bool activate=true);
-  void hide();
+  void on_hide() override;
   void search_and_replace_entry();
   void set_tab_entry();
   void goto_line_entry();