How do I sum all the values in column?

Caio.Sousa

I have this table:

void menupainel::listar(QString linea){


    QStringList A =linea.split("-");
    QString Descricao=A[0];
    QString Qntd=A[1];
    QString Preco=A[2];
    QString Total=A[3];

    ui->tableWidget_2->insertRow(ui->tableWidget_2->rowCount());
    ui->tableWidget_2->setItem(ui->tableWidget_2->rowCount()-1,0,new QTableWidgetItem(Descricao));
    ui->tableWidget_2->setItem(ui->tableWidget_2->rowCount()-1,1,new QTableWidgetItem(Qntd));
    ui->tableWidget_2->setItem(ui->tableWidget_2->rowCount()-1,2,new QTableWidgetItem(Preco));
    ui->tableWidget_2->setItem(ui->tableWidget_2->rowCount()-1,3,new QTableWidgetItem(Total));

    float myInt = 0;
     myInt = myInt + Total.toFloat();
    ui->txtTotalValor->setText(QString::number(myInt));



}

How do I sum all the values of the Total column display in a label?

Christian Ehrlicher

Iterate over all rows of your QTableWidget (QTableWidget::rowCount()), read the value from the item you want and sum it up.

Caio.Sousa

Did not quite understand

mrjj

@Caio.Sousa
Hi
You can just use for loop to loop over a row, or all rows.
This would loop over all rows, and all cols. ( only brain compiled)

int sum=0;
for (int i=0;i< ui->tableWidget->rowCount();i++) {
        for (int j=0;j< ui->tableWidget->columnCount();j++) {
            QTableWidgetItem *item =  ui->tableWidget->item(i,j);
            if ( ! item )  continue;
            int value = item->text().toInt(); // get its value
           sum+=value;
        }
    }

Caio.Sousa

@mrjj said in How do I sum all the values in column?:

int sum=0;
for (int i=0;i< ui->tableWidget->rowCount();i++) {
for (int j=0;j< ui->tableWidget->columnCount();j++) {
QTableWidgetItem *item = ui->tableWidget->item(i,j);
if ( ! item ) continue;
int value = item->text().toInt(); // get its value
sum+=value;
}
}

I Try this:

int sum=0;
    for (int i=0;i< ui->tableWidget->rowCount();i++) {
                QTableWidgetItem *item =  ui->tableWidget->item(i,A[3].toInt());
                if ( ! item )  continue;
                int value = item->text().toInt(); // get its value
               sum+=value;
            }

        ui->txtTotalValor->setText(QString::number(sum));

Because I want sum all values in column A[3],but it displays 0 in the interface

I did:

ui->txtTotalValor->setText(QString::number(sum));

aha_1980

@Caio.Sousa use the debugger to see where your error is...

mrjj

@Caio.Sousa said in How do I sum all the values in column?:

A[3].toInt()

Does this gives a valid column ?
Should be 3 as far as i can see.

Caio.Sousa

Yes, this column is valid, so it's strange, I split it from a file and got all values from column A [3]

mrjj

@Caio.Sousa
Ok, then we need to check if convert fails.
if not using the debugger, qDebug can be handy.

int sum=0;
    for (int i=0;i< ui->tableWidget->rowCount();i++) {
                QTableWidgetItem *item =  ui->tableWidget->item(i,A[3].toInt());
                if ( ! item )  continue;
                int value = item->text().toInt(); // get its value
               sum+=value;
               qDebug() << " values is " << value << " from text " << item->text();
            }

Caio.Sousa

Many thanks, I was doing wrong instead of just passing the value 3, I passed A [3].

I thought about what you had said and I took the test there.

How do I sum all the values ​​in column?

How do I sum all the values in column?