Use member function syntax for disconnect and KStandardAction connect

src/birthdaydlg.cpp

@@ -229,8 +229,8 @@ BirthdayDlg::BirthdayDlg(QWidget* parent)
 
 
     KActionCollection* actions = new KActionCollection(this);
-    KStandardAction::selectAll(mListView, SLOT(selectAll()), actions);
-    KStandardAction::deselect(mListView, SLOT(clearSelection()), actions);
+    KStandardAction::selectAll(mListView, &QTreeView::selectAll, actions);
+    KStandardAction::deselect(mListView, &QTreeView::clearSelection, actions);
     actions->addAssociatedWidget(mListView);
     const auto lstActions = actions->actions();
     for (QAction* action : lstActions)

src/templatedlg.cpp

@@ -104,9 +104,9 @@ TemplateDlg::TemplateDlg(QWidget* parent)
     topLayout->addWidget(buttonBox);
 
     KActionCollection* actions = new KActionCollection(this);
-    QAction* act = KStandardAction::selectAll(mListView, SLOT(selectAll()), actions);
+    QAction* act = KStandardAction::selectAll(mListView, &QTreeView::selectAll, actions);
     topLevelWidget()->addAction(act);
-    act = KStandardAction::deselect(mListView, SLOT(clearSelection()), actions);
+    act = KStandardAction::deselect(mListView, &QAbstractItemView::clearSelection, actions);
     topLevelWidget()->addAction(act);
     slotSelectionChanged();          // enable/disable buttons as appropriate
 

src/traywindow.cpp

@@ -84,14 +84,14 @@ TrayWindow::TrayWindow(MainWindow* parent)
     addAction(QStringLiteral("tSpread"), a);
     contextMenu()->addAction(a);
     contextMenu()->addSeparator();
-    contextMenu()->addAction(KStandardAction::preferences(this, SLOT(slotPreferences()), this));
+    contextMenu()->addAction(KStandardAction::preferences(this, &TrayWindow::slotPreferences, this));
 
-    // Disable standard quit behaviour. We have to intercept the quit even,
-    // if the main window is hidden.
+    // Disable standard quit behaviour. We have to intercept the quit event
+    // (which triggers KStatusNotifierItem to quit unconditionally).
     QAction* act = action(QStringLiteral("quit"));
     if (act)
     {
-        act->disconnect(SIGNAL(triggered(bool)), this, SLOT(maybeQuit()));
+        disconnect(act, &QAction::triggered, this, nullptr);
         connect(act, &QAction::triggered, this, &TrayWindow::slotQuit);
     }