QT中QListWidget窗口中条目更新，如何让它动态显示出来

我做的是一个公交车报站系统，在点击完模拟按钮后，会模拟走完整条路线，但是QListWidget不会动态更新，其中的数据处理部分还是会进行
附上模拟按钮的代码
/* simulate */
void MyDialog::on_pushButton_3_clicked()
{
while (1)
{
// 先清空显示
ui->listWidget->clear();

QFile file("bus_.xml");
if (!file.open(QIODevice::ReadOnly)) return ;
QDomDocument doc;
if (!doc.setContent(&file))
{
    file.close();
    return ;
}
file.close();

QDomElement docElem = doc.documentElement();
QDomElement c;
QString curstation;

int flag=0, count=0;

QDomNode n = docElem.firstChild();

while(!n.isNull())
{
    if (n.isElement())
    {
        QDomElement e = n.toElement();

        QDomNodeList list = e.childNodes();
        if (flag == 1)
        {
            for(int i=0; i<list.count(); i++)
            {
                QDomNode node = list.at(i);
                if(node.isElement())
                {
                    if (i == number)
                    {   qDebug()<<number;
                        //ui->listWidget->addItem(new QListWidgetItem(QIcon("yuan.jpg"), node.toElement().text()));
                        ui->listWidget->setCurrentItem(new QListWidgetItem(QIcon("yuan.jpg"), node.toElement().text()));
                        curstation = node.toElement().text();
                        qDebug()<<"next station"<<curstation;
                    }
                    else{
                        //ui->listWidget->addItem("           " + node.toElement().text());
                        ui->listWidget->setCurrentItem (new QListWidgetItem(QIcon("yuan.jpg"), node.toElement().text()));
                    }
                }
            }
        }
        else
        {
            QDomNode node_count = list.at(0);
            count = node_count.toElement().text().toInt();
            //qDebug()<<count;
        }

        flag++;
    }
    n = n.nextSibling();
}
//char command[256] = {0};
QString command;
command = _config_2() + curstation ;
qDebug()<<command;
/* yuying */
tts_open_test("/dev/ttyUSB0", (char *)command.toStdString().c_str());
/* net_demo_string */
/* string shuld be utf-8 */
net_demo_string((char *)command.toStdString().c_str());
qDebug()<<"net_demo_string";
/* maybe change */
QByteArray datagram = curstation.toStdString().c_str();
sender->writeDatagram (datagram.data(), datagram.size(), QHostAddress::Broadcast, 45454);
if (count == number)
{
    return ;
}
ui->listWidget->update ();
number++;
sleep(1);
}

}

    ui->listWidget_2->removeItemWidget(listWidgetItem);
    delete listWidgetItem;