QT自定义QTextEdit实现大数据的实时刷新显示功能实例

  mwarehouse.fill(QChar(),10*1024*1024);

void MainWindow::setDataToHouse(QString &str)
{
    int Maxsize = mwarehouse.size();
    if(str.size()>=Maxsize)
    {
        mwarehouse= str;
        return;
    }
    QString test = mwarehouse.mid(str.size(),-1);
    mwarehouse.replace(0,Maxsize-str.size(),mwarehouse.mid(str.size(),-1));
    mwarehouse.replace(Maxsize-str.size(),str.size(),str);
}

void MainWindow::showScrollContent(bool up)
{
    int Maxsize = mwarehouse.size();
    uint tmpsize = getScrollshowAreaSize();
    uint cursize = mtextedit->toPlainText().size();
    if(up)
    {
        if(cyclesnum<mlinenum){return;}
        mupnum+=tmpsize;
        cyclesnum-=  (mlinenum*2-1);
    }
    else{
        if(mupnum<tmpsize)
        {
           mupnum=0 ;
           return;
        }
        mupnum-=cursize;
    }
    QString allowString = mwarehouse.mid(Maxsize-tmpsize-mupnum,tmpsize);
    showString(allowString);
}

void MainWindow::showString(QString mess,bool cyc )
{
        if(cyc)
        {
            uint cycles = (mess.size())/(mlinenumsize);
            qDebug()<<"!!!!!"<<cycles;
            if(cycles>0)
            {
                for (uint i = 0;i<cycles ;++i ) {
                    showAllString(mess.mid(i*mlinenumsize,mlinenumsize));
                }
                mess = mess.mid(cycles*mlinenumsize,mess.size()-cycles*mlinenumsize);
            }
        }
        mtextedit->append(mess);
        ui->tb_linenum->append(QString::number(cyclesnum++));
}