QCoreApplication::sendPostedEvents: Cannot send posted events for objects in another thread

QCoreApplication::sendPostedEvents: Cannot send posted events for objects in another thread

在非GUI线程中操作继承自QObject的对象时会报出此错误，需改为在非GUI线程中发出信号，GUI线程中使用槽函数接收处理才能避免此错误。