I changed the widget to a QDoubleSpinBox which makes it easier to handle the values since I only want decimals at 0.5 steps.

Qt Code: 
  1. QDoubleSpinBox *quantitySpinBox = new QDoubleSpinBox();
  2.     quantitySpinBox->setDecimals(1);
  3.     quantitySpinBox->setSingleStep(0.5);
  4.     ui->treeWidget->setItemWidget(itm, 7, quantitySpinBox);
  5.  
  6.     connect(quantitySpinBox, SIGNAL(valueChanged(double)), this, SLOT(planQuantity()));
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But again when I try to access the value with the following code it does not return anything.

Qt Code: 
  1. for (int i = 0; i < ui->treeWidget->topLevelItemCount(); i++)
  2.     {
  3.         QTreeWidgetItem *item = ui->treeWidget->topLevelItem(i);
  4.         qDebug() << item->data(7, Qt::DisplayRole).toFloat();
  5.         quantity += item->text(7).toFloat();
  6.     }
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Any ideas on how to access a value in a widget within the QTreeWidgetItem?

Thanks,

Pericles