I’m pulling my hair out on this one and it’s probably something simple, but I can’t find it. I initially sub-classed QAbstractItemModel and everything seemed to work fine. I made what appeared to be unrelated changes in a different .cpp file when the program started reporting an ASSERT error. I believe I changed everything back, to the state it was in when it was working properly and yet it still reported the same error.

Using the debugger, I stepped through the program and found the location where the problem was starting. Surprisingly it was transpiring in the pure virtual function “data” at the line where I was checking if the request was referencing the TextAlignmentRole - line 116 in the code listing.

Qt Code: 
  1. 114	QVariant RDDSModel::data(const QModelIndex &index, int role) const
  2. 115	{
  3. 116		if (role == Qt::TextAlignmentRole)
  4.  
  5. 117			return Qt::AlignCenter;
  6. 118	
  7. 119		ModelItem* pItem;
  8. 120		if(role == Qt::DisplayRole){
  9. 121			if(index.isValid())
  10. 122				pItem = static_cast<ModelItem*>(index.internalPointer());
  11. 123			else
  12. 124				pItem = pRoot;
  13. 125			return pItem->getData(index.column());
  14. 126		}
  15. 127		return QVariant();
  16. 128	}
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The actual error message received is...

ASSERT failure in QVector<T>::at: "index out of range"

The debugger indicates that the error is being reported from qvector.h at line 429. Code shown...

Qt Code: 
  1. 427	template <typename T>
  2. 428	inline const T &QVector<T>::at(int i) const
  3. 429	{ Q_ASSERT_X(i >= 0 && i < d->size, "QVector<T>::at", "index out of range");
  4. 430	return d->begin()[i]; }
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At this time, I fail to seen any connection to the error message and the code where the error originated. Any help on this issue would be highly appreciated.