Qt-控件注册eventFilter后,控件消失

//xx.h
 
bool eventFilter(QObject *obj, QEvent *event)override;
//xx.cpp
xx(){
    ui->label->installEventFilter(this);
}
bool xx::eventFilter(QObject *obj, QEvent *event)
{
	....
    //这里不要返回ture或false
	return QWidget::eventFilter(obj, event);
}