class MainApplicationAdaptor: public QDBusAbstractAdaptor {     Q_OBJECT     Q_CLASSINFO("D-Bus Interface", "com.example.DBus.MainApplication")     Q_CLASSINFO("D-Bus Interface", "org.kde.DBus.MainApplication")     Q_PROPERTY(QString caption READ caption WRITE setCaption)     Q_PROPERTY(QString organizationName READ organizationName)     Q_PROPERTY(QString organizationDomain READ organizationDomain) private:     QApplication *app; public:     MyInterfaceAdaptor(QApplication *application)         : QDBusAbstractAdaptor(application), app(application)     {         connect(application, SIGNAL(aboutToQuit()), SIGNAL(aboutToQuit());         connect(application, SIGNAL(focusChanged(QWidget*, QWidget*)),                 SLOT(focusChangedSlot(QWidget*, QWidget*)));     }     QString caption()     {         if (app->hasMainWindow())             return app->mainWindow()->caption();         return QString(""); // must not return a null QString     }     void setCaption(const QString &newCaption)     {         if (app->hasMainWindow())             app->mainWindow()->setCaption(newCaption);     }     QString organizationName()     {         return app->organizationName();     }     QString organizationDomain()     {         return app->organizationDomain();     } public slots:     Q_ASYNC void quit()     { app->quit(); }     void reparseConfiguration()     { app->reparseConfiguration(); }     QString mainWindowObject()     {         if (app->hasMainWindow())             return QString("/%1/mainwindow").arg(app->applicationName());         return QString();     }     void setSessionManagement(bool enable)     {         if (enable)            app->enableSessionManagement();         else            app->disableSessionManagement();     } private slots:     void focusChangedSlot(QWidget *, QWidget *now)     {         if (now == app->mainWindow())             emit mainWindowHasFocus();     } signals:     void aboutToQuit();     void mainWindowHasFocus(); };