The Qt::ISODate format is YYYY-MM-DD for dates.
If you default the value to a date like above then the code that you used:
Qt Code:
  1. return value.toDate().toString(m_dateFormat);
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is correct, but if you default it in another form you should use a code like this one:
Qt Code:
  1. //myDateFormat is of type 'Qt::DateFormat' and is same as
  2. //the date format that you use for filling date cells.
  3. return QDate::fromString ( value.toString(), myDateFormat);
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