QTableWidget with setItem cannot access the data in the tablewidget - c++

Question

void IdListForTrain::SetListIdInList(QStringList IdList)
{
QTableWidgetItem *item=nullptr;
for(int index=0;index<IdList.count();index++)
{
ui->Id_tableWidget->insertRow(index);
for(qint32 columnIndex=0;columnIndex<=1;columnIndex++)
{
item = new QTableWidgetItem;
if(columnIndex==0)
{
ui->Id_tableWidget->setItem(index,columnIndex,item);
item->setText("00:00:00");
}
if(columnIndex==1)
{
ui->Id_tableWidget->setItem(index,columnIndex,item);
item->setText(IdList.at(index));
}
QString tmp1 = ui->Id_tableWidget->item(index,1)->text();
QString tmp = item->text();
}
}
}
Hi! I am new to Qt and I'm facing a problem. I was asked to create a tablewidget with the effective date of train Ids in one column and the names of the trains in another column,I did this code to the best of my knowledge but I can't set or access the data in the widget in the line eventhough the code doesnt give any errors but it crashes everytime I open the application window at this line,
QString tmp1 = ui->Id_tableWidget->item(index,1)->text();
I'm not sure what the reason is.

Answer 1

Let look at first iteration - index=0 and columnIndex=0.
You go through if(columnIndex==0) condition and set item to
QTableWidget's row = 0 (index) and column = 0 (columnIndex)
Second condition skipped
You try to access item at row = 0 (index) and column = 1 with code QString tmp1 = ui->Id_tableWidget->item(index,1)->text();. But at this time you have no item assigned to that column
That's all!