1. 信号槽
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QPushButton button("Quit");
QObject::connect(&button, &QPushButton::clicked, &QApplication::quit);
button.show();
return app.exec();
}
原文：https://www.cnblogs.com/luoyinjie/p/9745327.html