i create the model with column names:

class TreeModel : public QAbstractItemModel
{
public:
     explicit TreeModel(QList<QVariant> lstColumnNames, QObject *parent = nullptr) noexcept
            : QAbstractItemModel(parent)
            , m_lstColumnNames(std::move(lstColumnNames))

private:
     	QList<QVariant> m_lstColumnNames;

the reason i do this is to get tree header names and model column count:

QVariant TreeModel::headerData(int section, Qt::Orientation orientation, int role /* = Qt::DisplayRole */) const
{
	return orientation == Qt::Horizontal && role == Qt::DisplayRole
		? m_lstColumnNames[section]
		: QAbstractItemModel::headerData(section, orientation, role);
}

int TreeModel::columnCount(const QModelIndex &parent /* = QModelIndex() */) const
{
	return parent.isValid()
		? static_cast<TreeNode *>(parent.internalPointer())->columnCount()
		: m_lstColumnNames.size();
}

now, the problem is that, when i hide a column from context menu (and have 4 columns instead of 5), this list in model is not changed, i.e. columnCount() still returns the old 5.

one option i think of is to have list of pairs, QList<QPair<QVariant, bool>> m_lstColumnNames;, where the bool indicates whether the column is hidden or shown. that means i will need to update the column states every time i hide/show column from gui. also, to return column count i'd need to run over all columns and collect only visible ones.

i'd like to know what else can i do? probably something better.
thanks