QTableWidget and SQL (dynamic) not working

cxam

Hi!
In my program I have a QTableWidget that shows information queried, this is the code:

   int i = 0;
    while (query.next()) {
        //Establecemos un QTableWidget por cada columna
        ui->tableWidget->setItem(i,0,new QTableWidgetItem(query.value(0).toString()));
        ui->tableWidget->setItem(i,1,new QTableWidgetItem(query.value(1).toString()));
        ui->tableWidget->setItem(i,2,new QTableWidgetItem(query.value(2).toString()));
        ui->tableWidget->setItem(i,3,new QTableWidgetItem(query.value(3).toString()));
        ui->tableWidget->setItem(i,4,new QTableWidgetItem(query.value(4).toString()));
        ui->tableWidget->setItem(i,5,new QTableWidgetItem(query.value(5).toString()));
        ui->tableWidget->setItem(i,6,new QTableWidgetItem(query.value(6).toString()));
        ui->tableWidget->setItem(i,7,new QTableWidgetItem(query.value(7).toString()));
        i++;
        recCount++;
    }

Unfortunately it only shows 1 result even though the query is correct.

"i" is the number of the row and "recCount" doesn't has anything to do with the table.

Thanks in advance

SGaist

Hi,

You don't add any row to your QTableWidget or did you do before running that loop ?

Also, why not use a QTableView with QSqlQueryModel ?

cxam

@SGaist "i" is the number of rows that add's +1 at the end of the loop

cxam

@SGaist But how QtableView works ?

Joel Bodenmann

I can recommend reading these two articles to not only understand the model/view concept but also how Qt implements it:

As @SGaist pointed out there's an existing model that allows you to display SQL query results in a QTableView. The model is called QSqlQueryModel. You'd basically use a QTableView instead of a QTableWidget and use QTableView::setModel() to set the QSqlQueryModel as the model for the table view.

cxam

@Joel-Bodenmann I tried to use QTableView but actually it would break a lot of my code so unless it's completely necessary I won't use it. I'm focusing on trying to solve my current issue.

SGaist

What would break ?

In any case, I don't see you creating new rows. The incrementation of i doesn't mean your QTableWidget will have an additional row unless you did it before your while loop.

Joel Bodenmann

@cxam QTableWidget actually inherits from QTableView so it shouldn't break anything in terms of the GUI. In terms of the data handling: You just outsource that to the model. As there's an existing model that is designed specifically for handling SQL queries I can imagine that the only thing it would do is drastically simplify your life.
The QTableWidget really is just a QTableView with an internal model. That model is a generic model. Using the QTableView would allow you to use the SQL query specific QSqlQueryModel.

@SGaist QTableWidget::setItem() actually creates the row internally.

cxam

@Joel-Bodenmann Hmm I see. I'll check it out then, thanks for your help.

SGaist

@Joel-Bodenmann No it doesn't. First thing done, it checks whether the row, column combination returns a valid index if not then it returns immediately.

Joel Bodenmann

@SGaist Yes, you are correct. I am sorry for giving wrong information.

@cxam So as @SGaist pointed out in his first post: Make sure that your QTableWidget "has enough rows".
But anyway, I'd still recommend going with QTableView and QSqlQueryModel in your case.

cxam

@SGaist Indeed, you're right When I set the properties for my table I set that the number of rows was "1" so I have to create an "int" variable and then say that the number of rows is that variable starting from 1 and then increment that number on the loop.

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