QT设置二级菜单 QT获取命令行参数 QT获取系统环境变量 QT QStatusBar showMessage的坑
QT设置二级菜单QMenu*fileMenu=newQMenu(QStringLiteral("文件"),this->menuBar());this->menuBar()->addMenu(fileMenu);QAction*open=newQAction(QStringLiteral("打开"));QAction*close=newQAction(QStringLiteral("关闭"));QA