Refactor the MultiSettings class to work on Linux with Qt 5.5

This  change  to  using  dynamically   built  pop  up  menus  for  teh
configurations menu gets around an  issue with teh Linux Unity appmenu
not being able to handle actions used in multiple menu items.

There is  a remaining issue  with the QMenu::aboutToHide()  signal not
being fired if the Unity appmenu  is not disabled. Hopefully this will
be fixed  in later  Qt/Unity versions.  Until then  the configurations
menu cannot be used unless the appmenu_qt5 package is removed.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7260 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

MultiSettings.cpp

@@ -155,7 +155,8 @@ private:
   using Dictionary = QMap<QString, QVariant>;
 
   // create a configuration maintenance sub menu
-  QMenu * create_sub_menu (QMenu * parent,
+  QMenu * create_sub_menu (QMainWindow * main_window,
+			   QMenu * parent,
                            QString const& menu_title,
                            QActionGroup * = nullptr);
 
@@ -166,22 +167,22 @@ private:
   void load_from (Dictionary const&, bool add_placeholder = true);
 
   // switch to this configuration
-  void select_configuration (QMainWindow *);
+  void select_configuration (QMainWindow *, QMenu const *);
 
   // clone this configuration
-  void clone_configuration (QMenu *);
+  void clone_configuration (QMainWindow * main_window, QMenu *, QMenu const *);
 
   // update this configuration from another
-  void clone_into_configuration (QMainWindow *);
+  void clone_into_configuration (QMainWindow *, QMenu const *);
 
   // reset configuration to default values
-  void reset_configuration (QMainWindow *);
+  void reset_configuration (QMainWindow *, QMenu const *);
 
   // change configuration name
-  void rename_configuration (QMainWindow *);
+  void rename_configuration (QMainWindow *, QMenu *);
 
   // remove a configuration
-  void delete_configuration (QMainWindow *);
+  void delete_configuration (QMainWindow *, QMenu *);
 
   MultiSettings const * parent_;  // required for emitting signals
   bool name_change_emit_pending_; // delayed until menu built
@@ -195,14 +196,6 @@ private:
   bool exit_flag_;              // false means loop around with new
                                 // configuration
   QActionGroup * configurations_group_;
-  QAction * select_action_;
-  QAction * clone_action_;
-  QAction * clone_into_action_;
-  QAction * reset_action_;
-  QAction * rename_action_;
-  QAction * delete_action_;
-  QList<QMetaObject::Connection> action_connections_;
-  QMenu * active_sub_menu_;
 };
 
 #include "MultiSettings.moc"
@@ -277,13 +270,6 @@ MultiSettings::impl::impl (MultiSettings const * parent)
   , reposition_type_ {RepositionType::unchanged}
   , exit_flag_ {true}
   , configurations_group_ {new QActionGroup {this}}
-  , select_action_ {new QAction {tr ("&Switch To"), this}}
-  , clone_action_ {new QAction {tr ("&Clone"), this}}
-  , clone_into_action_ {new QAction {tr ("Clone &Into ..."), this}}
-  , reset_action_ {new QAction {tr ("R&eset"), this}}
-  , rename_action_ {new QAction {tr ("&Rename ..."), this}}
-  , delete_action_ {new QAction {tr ("&Delete"), this}}
-  , active_sub_menu_ {nullptr}
 {
   if (!settings_.isWritable ())
     {
@@ -373,7 +359,7 @@ bool MultiSettings::impl::reposition ()
         SettingsGroup alternatives {&settings_, multi_settings_root_group};
         {
           SettingsGroup purge_group {&settings_, current_};
-          settings_.remove ("");  // purge entire group
+          settings_.remove (QString {});  // purge entire group
         }
         // switch to the specified configuration name
         settings_.setValue (multi_settings_current_name_key, current_);
@@ -404,7 +390,7 @@ void MultiSettings::impl::create_menu_actions (QMainWindow * main_window, QMenu
   // get the current configuration name
   auto current_configuration_name = settings_.value (multi_settings_current_name_key, tr (default_string)).toString ();
   // add the default configuration sub menu
-  QMenu * default_menu = create_sub_menu (menu, current_configuration_name, configurations_group_);
+  QMenu * default_menu = create_sub_menu (main_window, menu, current_configuration_name, configurations_group_);
   // and set as the current configuration
   default_menu->menuAction ()->setChecked (true);
 
@@ -415,28 +401,9 @@ void MultiSettings::impl::create_menu_actions (QMainWindow * main_window, QMenu
   // add all the other configurations
   for (auto const& configuration_name: available_configurations)
     {
-      create_sub_menu (menu, configuration_name, configurations_group_);
+      create_sub_menu (main_window, menu, configuration_name, configurations_group_);
     }
 
-  // hook up configuration actions
-  action_connections_ << connect (select_action_, &QAction::triggered, [this, main_window] (bool) {
-      select_configuration (main_window);
-    });
-  action_connections_ << connect (clone_action_, &QAction::triggered, [this, menu] (bool) {
-      clone_configuration (menu);
-    });
-  action_connections_ << connect (clone_into_action_, &QAction::triggered, [this, main_window] (bool) {
-      clone_into_configuration (main_window);
-    });
-  action_connections_ << connect (rename_action_, &QAction::triggered, [this, main_window] (bool) {
-      rename_configuration (main_window);
-    });
-  action_connections_ << connect (reset_action_, &QAction::triggered, [this, main_window] (bool) {
-      reset_configuration (main_window);
-    });
-  action_connections_ << connect (delete_action_, &QAction::triggered, [this, main_window] (bool) {
-      delete_configuration (main_window);
-    });
   if (current_group.size ()) settings_.beginGroup (current_group);
 
   if (name_change_emit_pending_)
@@ -450,12 +417,6 @@ void MultiSettings::impl::create_menu_actions (QMainWindow * main_window, QMenu
 // main window really wants to quit or to run again with a new configuration
 bool MultiSettings::impl::exit ()
 {
-  for (auto const& connection: action_connections_)
-    {
-      disconnect (connection);
-    }
-  action_connections_.clear ();
-
   // ensure that configuration name changed signal gets fired on restart
   name_change_emit_pending_ = true;
 
@@ -463,32 +424,74 @@ bool MultiSettings::impl::exit ()
   return reposition ();
 }
 
-QMenu * MultiSettings::impl::create_sub_menu (QMenu * parent_menu,
+QMenu * MultiSettings::impl::create_sub_menu (QMainWindow * main_window,
+					      QMenu * parent_menu,
                                               QString const& menu_title,
                                               QActionGroup * action_group)
 {
   QMenu * sub_menu = parent_menu->addMenu (menu_title);
   if (action_group) action_group->addAction (sub_menu->menuAction ());
   sub_menu->menuAction ()->setCheckable (true);
-  sub_menu->addAction (select_action_);
-  sub_menu->addSeparator ();
-  sub_menu->addAction (clone_action_);
-  sub_menu->addAction (clone_into_action_);
-  sub_menu->addAction (rename_action_);
-  sub_menu->addAction (reset_action_);
-  sub_menu->addAction (delete_action_);
 
-  // disable disallowed actions before showing sub menu
+  // populate sub-menu actions before showing
-  connect (sub_menu, &QMenu::aboutToShow, [this, sub_menu] () {
+  connect (sub_menu, &QMenu::aboutToShow, [this, main_window, parent_menu, sub_menu] () {
       bool is_current {sub_menu->menuAction ()->text () == current_};
-      select_action_->setEnabled (!is_current);
+      if (!is_current)
-      delete_action_->setEnabled (!is_current);
+	{
+	  auto  * select_action = new QAction {tr ("&Switch To"), this};
+	  sub_menu->addAction (select_action);
+	  connect (select_action, &QAction::triggered, [this, main_window, sub_menu] (bool) {
+	      select_configuration (main_window, sub_menu);
+	    });
+	  sub_menu->addSeparator ();
+	}
+
+      auto * clone_action = new QAction {tr ("&Clone"), this};
+      sub_menu->addAction (clone_action);
+      connect (clone_action, &QAction::triggered, [this, main_window, parent_menu, sub_menu] (bool) {
+	  clone_configuration (main_window, parent_menu, sub_menu);
+	});
+
       auto const& current_group = settings_.group ();
       if (current_group.size ()) settings_.endGroup ();
       SettingsGroup alternatives {&settings_, multi_settings_root_group};
-      clone_into_action_->setEnabled (settings_.childGroups ().size ());
+      if (settings_.childGroups ().size ())
+	{
+	  auto * clone_into_action = new QAction {tr ("Clone &Into ..."), this};
+	  sub_menu->addAction (clone_into_action);
+	  connect (clone_into_action, &QAction::triggered, [this, main_window, sub_menu] (bool) {
+	      clone_into_configuration (main_window, sub_menu);
+	    });
+	}
       if (current_group.size ()) settings_.beginGroup (current_group);
-      active_sub_menu_ = sub_menu;
+      auto * reset_action = new QAction {tr ("R&eset"), this};
+      sub_menu->addAction (reset_action);
+      connect (reset_action, &QAction::triggered, [this, main_window, sub_menu] (bool) {
+	  reset_configuration (main_window, sub_menu);
+	});
+
+      auto * rename_action = new QAction {tr ("&Rename ..."), this};
+      sub_menu->addAction (rename_action);
+      connect (rename_action, &QAction::triggered, [this, main_window, sub_menu] (bool) {
+	  rename_configuration (main_window, sub_menu);
+	});
+
+      if (!is_current)
+	{
+	  auto * delete_action = new QAction {tr ("&Delete"), this};
+	  sub_menu->addAction (delete_action);
+	  connect (delete_action, &QAction::triggered, [this, main_window, sub_menu] (bool) {
+	      delete_configuration (main_window, sub_menu);
+	    });
+	}
+    });
+
+  // depopulate sub-menu actions before hiding
+  connect (sub_menu, &QMenu::aboutToHide, [this, sub_menu] () {
+      while (!sub_menu->actions ().isEmpty ())
+	{
+	  sub_menu->removeAction (sub_menu->actions ().last ());
+	}
     });
 
   return sub_menu;
@@ -529,256 +532,238 @@ void MultiSettings::impl::load_from (Dictionary const& dictionary, bool add_plac
   settings_.sync ();
 }
 
-void MultiSettings::impl::select_configuration (QMainWindow * main_window)
+void MultiSettings::impl::select_configuration (QMainWindow * main_window, QMenu const * menu)
 {
-  if (active_sub_menu_)
+  auto const& target_name = menu->title ();
+
+  if (target_name != current_)
     {
-      auto const& target_name = active_sub_menu_->title ();
-
-      if (target_name != current_)
-        {
-          {
-            auto const& current_group = settings_.group ();
-            if (current_group.size ()) settings_.endGroup ();
-            // position to the alternative settings
-            SettingsGroup alternatives {&settings_, multi_settings_root_group};
-            // save the target settings
-            SettingsGroup target_group {&settings_, target_name};
-            new_settings_ = get_settings ();
-            if (current_group.size ()) settings_.beginGroup (current_group);
-          }
-          // and set up the restart
-          current_ = target_name;
-          Q_EMIT parent_->configurationNameChanged (current_);
-          reposition_type_ = RepositionType::save_and_replace;
-          exit_flag_ = false;
-          main_window->close ();
-        }
-    }
-}
-
-void MultiSettings::impl::clone_configuration (QMenu * menu)
-{
-  if (active_sub_menu_)
-    {
-      auto const& current_group = settings_.group ();
-      if (current_group.size ()) settings_.endGroup ();
-      auto const& source_name = active_sub_menu_->title ();
-
-      // settings to clone
-      Dictionary source_settings;
-      if (source_name == current_)
-        {
-          // grab the data to clone from the current settings
-          source_settings = get_settings ();
-        }
-      SettingsGroup alternatives {&settings_, multi_settings_root_group};
-      if (source_name != current_)
-        {
-          SettingsGroup source_group {&settings_, source_name};
-          source_settings = get_settings ();
-        }
-
-      // find a new unique name
-      QString new_name_root {source_name + " - Copy"};;
-      QString new_name {new_name_root};
-      unsigned index {0};
-      do
-        {
-          if (index++) new_name = new_name_root + '(' + QString::number (index) + ')';
-        }
-      while (settings_.childGroups ().contains (new_name));
-      SettingsGroup new_group {&settings_, new_name};
-      load_from (source_settings);
-
-      // insert the new configuration sub menu in the parent menu
-      create_sub_menu (menu, new_name, configurations_group_);
-      if (current_group.size ()) settings_.beginGroup (current_group);
-    }
-}
-
-void MultiSettings::impl::clone_into_configuration (QMainWindow * main_window)
-{
-  if (active_sub_menu_)
-    {
-      auto const& current_group = settings_.group ();
-      if (current_group.size ()) settings_.endGroup ();
-      auto const& target_name = active_sub_menu_->title ();
-
-      // get the current configuration name
-      QString current_group_name;
-      QStringList sources;
       {
-        SettingsGroup alternatives {&settings_, multi_settings_root_group};
+	auto const& current_group = settings_.group ();
-        current_group_name = settings_.value (multi_settings_current_name_key).toString ();
+	if (current_group.size ()) settings_.endGroup ();
-
+	// position to the alternative settings
-        {
+	SettingsGroup alternatives {&settings_, multi_settings_root_group};
-          // get the source configuration name for the clone
+	// save the target settings
-          sources = settings_.childGroups ();
+	SettingsGroup target_group {&settings_, target_name};
-          sources << current_group_name;
+	new_settings_ = get_settings ();
-          sources.removeOne (target_name);
+	if (current_group.size ()) settings_.beginGroup (current_group);
-        }
       }
-
+      // and set up the restart
-      // pick a source configuration
+      current_ = target_name;
-      ExistingNameDialog dialog {sources, main_window};
+      Q_EMIT parent_->configurationNameChanged (current_);
-      if (sources.size () && (1 == sources.size () || QDialog::Accepted == dialog.exec ()))
+      reposition_type_ = RepositionType::save_and_replace;
-        {
+      exit_flag_ = false;
-          QString source_name {1 == sources.size () ? sources.at (0) : dialog.name ()};
+      main_window->close ();
-          if (MessageBox::Yes == MessageBox::query_message (main_window,
-                                                            tr ("Clone Into Configuration"),
-                                                            tr ("Confirm overwrite of all values for configuration \"%1\" with values from \"%2\"?")
-                                                            .arg (target_name)
-                                                            .arg (source_name)))
-            {
-              // grab the data to clone from
-              if (source_name == current_group_name)
-                {
-                  // grab the data to clone from the current settings
-                  new_settings_ = get_settings ();
-                }
-              else
-                {
-                  SettingsGroup alternatives {&settings_, multi_settings_root_group};
-                  SettingsGroup source_group {&settings_, source_name};
-                  new_settings_ = get_settings ();
-                }
-
-              // purge target settings and replace
-              if (target_name == current_)
-                {
-                  // restart with new settings
-                  reposition_type_ = RepositionType::replace;
-                  exit_flag_ = false;
-                  main_window->close ();
-                }
-              else
-                {
-                  SettingsGroup alternatives {&settings_, multi_settings_root_group};
-                  SettingsGroup target_group {&settings_, target_name};
-                  settings_.remove (""); // purge entire group
-                  load_from (new_settings_);
-                  new_settings_.clear ();
-                }
-            }
-        }
-      if (current_group.size ()) settings_.beginGroup (current_group);
     }
 }
 
-void MultiSettings::impl::reset_configuration (QMainWindow * main_window)
+void MultiSettings::impl::clone_configuration (QMainWindow * main_window, QMenu * parent_menu, QMenu const * menu)
 {
-  if (active_sub_menu_)
+  auto const& current_group = settings_.group ();
+  if (current_group.size ()) settings_.endGroup ();
+  auto const& source_name = menu->title ();
+
+  // settings to clone
+  Dictionary source_settings;
+  if (source_name == current_)
     {
-      auto const& target_name = active_sub_menu_->title ();
+      // grab the data to clone from the current settings
-
+      source_settings = get_settings ();
-      if (MessageBox::Yes != MessageBox::query_message (main_window,
-                                                        tr ("Reset Configuration"),
-                                                        tr ("Confirm reset to default values for configuration \"%1\"?")
-                                                        .arg (target_name)))
-        {
-          return;
-        }
-
-      if (target_name == current_)
-        {
-          // restart with default settings
-          reposition_type_ = RepositionType::replace;
-          new_settings_.clear ();
-          exit_flag_ = false;
-          main_window->close ();
-        }
-      else
-        {
-          auto const& current_group = settings_.group ();
-          if (current_group.size ()) settings_.endGroup ();
-          SettingsGroup alternatives {&settings_, multi_settings_root_group};
-          SettingsGroup target_group {&settings_, target_name};
-          settings_.remove (""); // purge entire group
-          // add a placeholder to stop alternative configuration name
-          // being lost
-          settings_.setValue (multi_settings_place_holder_key, QVariant {});
-          settings_.sync ();
-          if (current_group.size ()) settings_.beginGroup (current_group);
-        }
     }
+  SettingsGroup alternatives {&settings_, multi_settings_root_group};
+  if (source_name != current_)
+    {
+      SettingsGroup source_group {&settings_, source_name};
+      source_settings = get_settings ();
+    }
+
+  // find a new unique name
+  QString new_name_root {source_name + " - Copy"};;
+  QString new_name {new_name_root};
+  unsigned index {0};
+  do
+    {
+      if (index++) new_name = new_name_root + '(' + QString::number (index) + ')';
+    }
+  while (settings_.childGroups ().contains (new_name) || new_name == current_);
+  SettingsGroup new_group {&settings_, new_name};
+  load_from (source_settings);
+
+  // insert the new configuration sub menu in the parent menu
+  create_sub_menu (main_window, parent_menu, new_name, configurations_group_);
+  if (current_group.size ()) settings_.beginGroup (current_group);
 }
 
-void MultiSettings::impl::rename_configuration (QMainWindow * main_window)
+void MultiSettings::impl::clone_into_configuration (QMainWindow * main_window, QMenu const * menu)
 {
-  if (active_sub_menu_)
+  auto const& current_group = settings_.group ();
+  if (current_group.size ()) settings_.endGroup ();
+  auto const& target_name = menu->title ();
+
+  // get the current configuration name
+  QString current_group_name;
+  QStringList sources;
+  {
+    SettingsGroup alternatives {&settings_, multi_settings_root_group};
+    current_group_name = settings_.value (multi_settings_current_name_key).toString ();
+
+    {
+      // get the source configuration name for the clone
+      sources = settings_.childGroups ();
+      sources << current_group_name;
+      sources.removeOne (target_name);
+    }
+  }
+
+  // pick a source configuration
+  ExistingNameDialog dialog {sources, main_window};
+  if (sources.size () && (1 == sources.size () || QDialog::Accepted == dialog.exec ()))
+    {
+      QString source_name {1 == sources.size () ? sources.at (0) : dialog.name ()};
+      if (MessageBox::Yes == MessageBox::query_message (main_window,
+							tr ("Clone Into Configuration"),
+							tr ("Confirm overwrite of all values for configuration \"%1\" with values from \"%2\"?")
+							.arg (target_name)
+							.arg (source_name)))
+	{
+	  // grab the data to clone from
+	  if (source_name == current_group_name)
+	    {
+	      // grab the data to clone from the current settings
+	      new_settings_ = get_settings ();
+	    }
+	  else
+	    {
+	      SettingsGroup alternatives {&settings_, multi_settings_root_group};
+	      SettingsGroup source_group {&settings_, source_name};
+	      new_settings_ = get_settings ();
+	    }
+
+	  // purge target settings and replace
+	  if (target_name == current_)
+	    {
+	      // restart with new settings
+	      reposition_type_ = RepositionType::replace;
+	      exit_flag_ = false;
+	      main_window->close ();
+	    }
+	  else
+	    {
+	      SettingsGroup alternatives {&settings_, multi_settings_root_group};
+	      SettingsGroup target_group {&settings_, target_name};
+	      settings_.remove (QString {}); // purge entire group
+	      load_from (new_settings_);
+	      new_settings_.clear ();
+	    }
+	}
+    }
+  if (current_group.size ()) settings_.beginGroup (current_group);
+}
+
+void MultiSettings::impl::reset_configuration (QMainWindow * main_window, QMenu const * menu)
+{
+  auto const& target_name = menu->title ();
+
+  if (MessageBox::Yes != MessageBox::query_message (main_window,
+						    tr ("Reset Configuration"),
+						    tr ("Confirm reset to default values for configuration \"%1\"?")
+						    .arg (target_name)))
+    {
+      return;
+    }
+
+  if (target_name == current_)
+    {
+      // restart with default settings
+      reposition_type_ = RepositionType::replace;
+      new_settings_.clear ();
+      exit_flag_ = false;
+      main_window->close ();
+    }
+  else
     {
       auto const& current_group = settings_.group ();
       if (current_group.size ()) settings_.endGroup ();
-      auto const& target_name = active_sub_menu_->title ();
-
-      // gather names we cannot use
       SettingsGroup alternatives {&settings_, multi_settings_root_group};
-      auto invalid_names = settings_.childGroups ();
+      SettingsGroup target_group {&settings_, target_name};
-      invalid_names << settings_.value (multi_settings_current_name_key).toString ();
+      settings_.remove (QString {}); // purge entire group
-
+      // add a placeholder to stop alternative configuration name
-      // get the new name
+      // being lost
-      NameDialog dialog {target_name, invalid_names, main_window};
+      settings_.setValue (multi_settings_place_holder_key, QVariant {});
-      if (QDialog::Accepted == dialog.exec ())
+      settings_.sync ();
-        {
-          if (target_name == current_)
-            {
-              settings_.setValue (multi_settings_current_name_key, dialog.new_name ());
-              settings_.sync ();
-              current_ = dialog.new_name ();
-              Q_EMIT parent_->configurationNameChanged (current_);
-            }
-          else
-            {
-              // switch to the target group and fetch the configuration data
-              Dictionary target_settings;
-              {
-                // grab the target configuration settings
-                SettingsGroup target_group {&settings_, target_name};
-                target_settings = get_settings ();
-                // purge the old configuration data
-                settings_.remove (""); // purge entire group
-              }
-              // load into new configuration group name
-              SettingsGroup target_group {&settings_, dialog.new_name ()};
-              load_from (target_settings);
-            }
-          // change the action text in the menu
-          active_sub_menu_->setTitle (dialog.new_name ());
-        }
       if (current_group.size ()) settings_.beginGroup (current_group);
     }
 }
 
-void MultiSettings::impl::delete_configuration (QMainWindow * main_window)
+void MultiSettings::impl::rename_configuration (QMainWindow * main_window, QMenu * menu)
 {
-  if (active_sub_menu_)
+  auto const& current_group = settings_.group ();
-    {
+  if (current_group.size ()) settings_.endGroup ();
-      auto const& target_name = active_sub_menu_->title ();
+  auto const& target_name = menu->title ();
 
+  // gather names we cannot use
+  SettingsGroup alternatives {&settings_, multi_settings_root_group};
+  auto invalid_names = settings_.childGroups ();
+  invalid_names << settings_.value (multi_settings_current_name_key).toString ();
+
+  // get the new name
+  NameDialog dialog {target_name, invalid_names, main_window};
+  if (QDialog::Accepted == dialog.exec ())
+    {
       if (target_name == current_)
-        {
+	{
-          return;               // suicide not allowed here
+	  settings_.setValue (multi_settings_current_name_key, dialog.new_name ());
-        }
+	  settings_.sync ();
+	  current_ = dialog.new_name ();
+	  Q_EMIT parent_->configurationNameChanged (current_);
+	}
       else
-        {
+	{
-          if (MessageBox::Yes != MessageBox::query_message (main_window,
+	  // switch to the target group and fetch the configuration data
-                                                            tr ("Delete Configuration"),
+	  Dictionary target_settings;
-                                                            tr ("Confirm deletion of configuration \"%1\"?")
+	  {
-                                                            .arg (target_name)))
+	    // grab the target configuration settings
-            {
+	    SettingsGroup target_group {&settings_, target_name};
-              return;
+	    target_settings = get_settings ();
-            }
+	    // purge the old configuration data
-          auto const& current_group = settings_.group ();
+	    settings_.remove (QString {}); // purge entire group
-          if (current_group.size ()) settings_.endGroup ();
+	  }
-          SettingsGroup alternatives {&settings_, multi_settings_root_group};
+	  // load into new configuration group name
-          SettingsGroup target_group {&settings_, target_name};
+	  SettingsGroup target_group {&settings_, dialog.new_name ()};
-          // purge the configuration data
+	  load_from (target_settings);
-          settings_.remove (""); // purge entire group
+	}
-          settings_.sync ();
+      // change the action text in the menu
-          if (current_group.size ()) settings_.beginGroup (current_group);
+      menu->setTitle (dialog.new_name ());
-        }
-      // update the menu
-      active_sub_menu_->deleteLater (), active_sub_menu_ = nullptr;
     }
+  if (current_group.size ()) settings_.beginGroup (current_group);
+}
+
+void MultiSettings::impl::delete_configuration (QMainWindow * main_window, QMenu * menu)
+{
+  auto const& target_name = menu->title ();
+
+  if (target_name == current_)
+    {
+      return;               // suicide not allowed here
+    }
+  else
+    {
+      if (MessageBox::Yes != MessageBox::query_message (main_window,
+							tr ("Delete Configuration"),
+							tr ("Confirm deletion of configuration \"%1\"?")
+							.arg (target_name)))
+	{
+	  return;
+	}
+      auto const& current_group = settings_.group ();
+      if (current_group.size ()) settings_.endGroup ();
+      SettingsGroup alternatives {&settings_, multi_settings_root_group};
+      SettingsGroup target_group {&settings_, target_name};
+      // purge the configuration data
+      settings_.remove (QString {}); // purge entire group
+      settings_.sync ();
+      if (current_group.size ()) settings_.beginGroup (current_group);
+    }
+  // update the menu
+  menu->deleteLater ();
 }