the question about define my own selection behavior

[shentian]

You don't need to modify the selection model. You can tell the view which items can be selected by using the Qt::ItemIsSelectable flag in your data model.

Inherit your model and overwrite QAbstractItemModel::flags:

Qt::ItemFlags MyModel::flags(const QModelIndex& index) const
{
  if (/* user is allowd to select index.row() */)
    return QAbstractTableModel::flags(index) | Qt::ItemIsSelectable;
  else
    return QAbstractTableModel::flags(index) & ~Qt::ItemIsSelectable;
}

Qt::ItemFlags MyModel::flags(const QModelIndex& index) const
{
  if (/* user is allowd to select index.row() */)
    return QAbstractTableModel::flags(index) | Qt::ItemIsSelectable;
  else
    return QAbstractTableModel::flags(index) & ~Qt::ItemIsSelectable;
}

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