saveAction = new QAction(tr("&Save"), this);
exitAction = new QAction(tr("E&xit"), this);
connect(openAction, &QAction::triggered,
this, &Mainwindow::open);
saveAction = new QAction(tr("&Save"), this);
exitAction = new QAction(tr("E&xit"), this);
connect(openAction, &QAction::triggered,
this, &Mainwindow::open);