宏定义：

Q_GLOBAL_STATIC(NotifyManager,theInstance)

函数定义：

class NotifyManager  : public QObject
{Q_OBJECTpublic:NotifyManager(QObject *parent = nullptr);~NotifyManager();static NotifyManager*getInstance();  //单例模式
}

源代码：

NotifyManager * NotifyManager::getInstance() {return theInstance();
}