1. You have to set the item value :
Qt Code:
  1. for(int i = 1; i < 31; i++)
  2. {
  3. ui->combo->addItem(QString::number(i),i);
  4. }
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2. To get selected item value :
Qt Code:
  1. int value = ui->combo->itemValue(ui->combo->currentIndex());
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