qt 拷贝文件设置进度条

/**
 * @brief FuncModuleWin::copyFile 
 * @param fromFIleName 优盘里面的文件
 * @param toFileName 拷贝到/bin里面的启动文件
 * @return
 */
bool FuncModuleWin::copyFile(const QString &fromFIleName, const QString &toFileName)
{
    char* byteTemp = new char[4096];//字节数组
    int fileSize = 0;
    int totalCopySize = 0;
    QFile tofile;
    ui->progressBar_copy->setValue(0);
    tofile.setFileName(toFileName);
    QDataStream out(&tofile);
    out.setVersion(QDataStream::Qt_4_8);

    QFile fromfile;
    fromfile.setFileName(fromFIleName);
    if(!fromfile.open(QIODevice::ReadOnly)){
        qDebug() << "open fromfile failed！！！";
        return false;
    }
    fileSize = fromfile.size();
    QDataStream in(&fromfile);

    in.setVersion(QDataStream::Qt_4_8);
    ui->progressBar_copy->setRange(0, fileSize);
    while(!in.atEnd())
    {
        int readSize = 0;
        //读入字节数组,返回读取的字节数量，如果小于4096，则到了文件尾
        readSize = in.readRawData(byteTemp, 4096);
        out.writeRawData(byteTemp, readSize);
        totalCopySize += readSize;
        ui->progressBar_copy->setValue(totalCopySize);
    }
    if(totalCopySize == fileSize){
        tofile.setPermissions(QFile::ExeUser);
        return true;
    }
    else
        return false;
}