Two advanced playing methods of QT signal and slot

A preliminary study of playing methods

Function wrapper as slot

    ///>1 std::function
    //    std::function<void(QString)> f_add_display = std::bind(&NOISTMain::btnClicked, this, std::placeholders::_1);
    //    dlgManage->show_dialog(f_add_display);

    ///>2 std::function
    //    std::function<void(QString nn)> f_display_1 = [](QString nn) { qDebug() &