ColumnProxy

//////////////////////////////////////////////////////////////////////////
// ColumnsToRolesProxy.h
//////////////////////////////////////////////////////////////////////////
#ifndef COLUMNSTOROLESPROXY_H
#define COLUMNSTOROLESPROXY_H

#include <QIdentityProxyModel>

class ColumnsToRolesProxy : public QIdentityProxyModel
{
    Q_OBJECT

public:
    ColumnsToRolesProxy(QObject *parent=nullptr);
    virtual ~ColumnsToRolesProxy() = default;
    virtual QHash<int, QByteArray> roleNames() const override;
    virtual QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
    virtual bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole) override;
    virtual int columnCount(const QModelIndex &parent = QModelIndex()) const override;
    enum{
        FirstColumnShift = 10
    };
};

#endif // COLUMNSTOROLESPROXY_H

//////////////////////////////////////////////////////////////////////////
// ColumnsToRolesProxy.cpp
//////////////////////////////////////////////////////////////////////////
#include "ColumnsToRolesProxy.h"

ColumnsToRolesProxy::ColumnsToRolesProxy(QObject *parent)
    : QIdentityProxyModel(parent)
{}

QHash<int, QByteArray> ColumnsToRolesProxy::roleNames() const
{
    QHash<int, QByteArray> result = QIdentityProxyModel::roleNames();
    QList<int> baseRoles = result.keys();
    baseRoles.removeAll(Qt::DisplayRole);
    for (int i = 0; i < sourceModel()->columnCount();++i){
        result[(i << FirstColumnShift) | Qt::DisplayRole] = sourceModel()->headerData(i, Qt::Horizontal, Qt::DisplayRole).toByteArray();
        for (auto j = baseRoles.constBegin(); j != baseRoles.constEnd(); ++j) {
            result.insert((i << FirstColumnShift) | *j, "col" + QByteArray::number(i) + result.value(*j));
        }
    }

    return result;
}

QVariant ColumnsToRolesProxy::data(const QModelIndex &index, int role) const
{
    return sourceModel()->data(sourceModel()->index(index.row(), role >> FirstColumnShift, index.parent()), role & ((1 << FirstColumnShift) - 1));
}

bool ColumnsToRolesProxy::setData(const QModelIndex &index, const QVariant &value, int role)
{
    return sourceModel()->setData(sourceModel()->index(index.row(), role >> FirstColumnShift, index.parent()), value, role & ((1 << FirstColumnShift) - 1));
}

int ColumnsToRolesProxy::columnCount(const QModelIndex &parent) const
{
    return qMin(1, QIdentityProxyModel::columnCount(parent));
}