代码太啰嗦了,比如就用QLabel吧,用的时候
QLabel *label = new QLabel("xxxx", this);
label->show();
QTimer::singleShot(3000, label, SLOT(deleteLater()));
或者
QLabel *label = new QLabel("xxxx", this);
label->setAttribute(Qt::WA_DeleteOnClose, true);
label->show();
QTimer::singleShot(3000, label, SLOT(close()));