Qt::ToolTipRole not getting triggered - qt

Question

I am using a model implemented using QAbstractTableModel. I want to show individual tooltips for all the headers. In the data() and headerData() implementations, however, When I print the role, it is never becoming Qt::ToolTipRole. Is there anything else I have to do to trigger the tooltiprole here?
QVariant jlsGenericReportTableModel::data(const QModelIndex &index, int role) const
{
printf("Role in data() = %d\n",role);
if (role == Qt::DisplayRole)
{
// printf(" --- Returned\n");
if(_dataStore)
{
if(index.row() < _dataStore->RowCount())
{
return _dataStore->DataForTuple(index.row(),index.column());
}
}
else
{
if(index.row() < _rows.size())
{
return _rows.at(index.row())->DataForColumn(index.column());
}
}
}
else if (role == Qt::TextAlignmentRole )
{
if (( (QMetaType::Type)(data(index,Qt::DisplayRole)).type()) == QMetaType::QString)
return QVariant(Qt::AlignLeft | Qt::AlignVCenter);
else
return QVariant(Qt::AlignRight | Qt::AlignVCenter);
}
else if (role == Qt::ToolTipRole) {
printf("Triggered\n"); //Doesn't come here
//if (orientation == Qt::Horizontal)
return QString("Horizontal Header No. ");
//else
// return QString("Vertical Header No. ");
}
return QVariant();
}