connect(trayIcon, SIGNAL(activated(QSystemTrayIcon::ActivationReason)), this, SLOT(trayIconActivated(QSystemTrayIcon::ActivationReason)));//...void MainWindow::trayIconActivated(QSystemTrayIcon::ActivationReason reason){ switch(reason) { case QSystemTrayIcon::Trigger:{QDialog* f = new QDialog(this);f->setWindowFlags(f->windowFlags() | Qt::WindowStaysOnTopHint);f->show();//f->setWindowState(windowState() & ~Qt::WindowMinimized);f->raise();f->activateWindow();} default: break; }}