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Add hash function to saving in csv



  • Hi!
    A week ago, I was able to solve one problem. ( https://forum.qt.io/topic/65110/encoding-in-the-qtableview ). Thanks to @mrjj and @SGaist .

    In the previous function I wrote:

    ui->tableView_3->setModel(model);
    ui->tableView_3->setItemDelegateForColumn(3, new MyDelegate(this));
    

    But now I want to save that table in csv format with the hash function.
    This is the working code that can save table into csv file without transforming.

    void MainWindow::on_pushButton3_2_clicked()
    { QSqlQueryModel * model = new QSqlQueryModel(0);
    QString filename=QFileDialog::getSaveFileName(
                this,
                tr("Save as"),
                "C://",
                "CSV files (*.csv)"        );
        QFile f(filename);
            if( f.open( QIODevice::WriteOnly ) )
            {
                QTextStream ts( &f );
                QStringList strList;
                strList << "\" \"";
                for( int c = 0; c < ui->tableView_3->horizontalHeader()->count(); ++c )
                    strList << "\""+ui->tableView_3->model()->headerData(c, Qt::Horizontal).toString()+"\"";
                ts << strList.join( ";" )+"\n";
                for( int r = 0; r < ui->tableView_3->verticalHeader()->count(); ++r )
                {
                    strList.clear();
                    strList << "\""+ui->tableView_3->model()->headerData(r, Qt::Vertical).toString()+"\"";
                    for( int c = 0; c < ui->tableView_3->horizontalHeader()->count(); ++c )
                    {
                        strList << "\""+ui->tableView_3->model()->data(ui->tableView_3->model()->index(r, c), Qt::DisplayRole).toString()+"\"";
                    }
                    ts << strList.join( ";" )+"\n";
                }
                f.close();
            }
    }
    
    

    It's working, but how to add here hash function that will transform values?


  • Lifetime Qt Champion

    hi
    you just need to call like before
    QString CityName = hash[value];
    so u need the same hash here.
    U can either make a new one here.
    (reading 40 values is no big deal)
    or re-arrange the code so this function/class can also use the existing hash.

    QString CityName = hash[value];
    value is
    ui->tableView_3->model()->data(ui->tableView_3->model()->index(r, c), Qt::DisplayRole).toString()
    when "c" is the correct column. ( u must use if to test for that)



  • @mrjj said:

    or re-arrange the code so this function/class can also use the existing hash.

    QString CityName = hash[value];
    value is
    ui->tableView_3->model()->data(ui->tableView_3->model()->index(r, c), Qt::DisplayRole).toString()
    when "c" is the correct column. ( u must use if to test for that)

    I think I don't understand you well. Why I can't just paste that code with little transformation?(if it need to use) .

    ui->tableView_2->setItemDelegateForColumn(3, new MyDelegate(this));
    

    And do you mean that I should write that? But it won't work( or not)?

    QString CityName = hash[ ui->tableView_3->model()->data(ui->tableView_3->model()->index(r, c), Qt::DisplayRole).toString()]
    

  • Lifetime Qt Champion

    @ro12man3

    • Why I can't just paste that code with little transformation
      Because the delegate replace the text (data) when showing it.
      Now you are reading data directly to save it and
      ui->tableView_3->model()->data return the original data, there is no delegate in between to
      translate.
      So you must do it. (again)
      And yes like you show, but ONLY when c is the COL you want to convert.
      and then write out cityname and not directly from data.


  • @mrjj I really don't understand the method for solving that problem.

    This is the project with all functions: saving in csv(after clicking on the button) and the hash function(thanks :D)
    http://rghost.ru/62XsMLmDk
    Can you watch what I should to change? My skills are better now, but insufficiently


  • Lifetime Qt Champion

    @ro12man3

    You must use the hash again,
    so i moved the code into function.
    that way we can also create a hash when exporting.

    https://www.dropbox.com/s/6oqbcvcz006kzeh/myfristview_hash3.zip?dl=0

    Note I copy the hash, so if u had 10000000 items, it would not be the way to do it.



  • @mrjj Thank you, now I understand.



  • @mrjj I found the bag. It is changing ALL columns, how to do it only for one column?
    I have edited the code on that:

      QString value = uimodel->data(uimodel->index(r, 3), Qt::DisplayRole).toString();
    

    but then it will duplicate that column to all another.


  • Lifetime Qt Champion

    @ro12man3
    oh the test had only one COL so didn't check

    you do
    for( int c = 0; c < ui->tableView->horizontalHeader()->count()
    ...
    so you should only do it when c == the_right_col

    you could

    ...
         if (c == 3)
            strList << "\"" + mapped + "\"";
            else
            strList << "\"" + value + "\"";
    


  • @mrjj yeeeep! it's working! thank you!


  • Lifetime Qt Champion

    @ro12man3 said:
    super :)


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