src_corelib_kernel_qabstractitemmodel.cpp

Go to the documentation of this file.

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
#include <QSortFilterProxyModel>
#include <QVariant>
#include <QModelIndex>
#include <QModelRoleDataSpan>
#include <QAbstractItemModel>
 
class MyModel : public QAbstractItemModel
{
public:
    void multiData(const QModelIndex &index, QModelRoleDataSpan roleDataSpan) const override;
 
    QVariant data(const QModelIndex &index, int role) const override;
 
    void methods_calls(QModelIndex &parent,
        QModelIndex &sourceParent,
        QModelIndex &destinationParent)
    {
        //! [0]
        beginInsertRows(parent, 2, 4);
        //! [0]
 
 
        //! [1]
        beginInsertRows(parent, 4, 5);
        //! [1]
 
 
        //! [2]
        beginRemoveRows(parent, 2, 3);
        //! [2]
 
 
        //! [3]
        beginInsertColumns(parent, 4, 6);
        //! [3]
 
 
        //! [4]
        beginInsertColumns(parent, 6, 8);
        //! [4]
 
 
        //! [5]
        beginRemoveColumns(parent, 4, 6);
        //! [5]
 
 
        //! [6]
        beginMoveRows(sourceParent, 2, 4, destinationParent, 2);
        //! [6]
 
 
        //! [7]
        beginMoveRows(sourceParent, 2, 4, destinationParent, 6);
        //! [7]
 
 
        //! [8]
        beginMoveRows(parent, 2, 2, parent, 0);
        //! [8]
 
 
        //! [9]
        beginMoveRows(parent, 2, 2, parent, 4);
        //! [9]
    }
};
 
//! [12]
class CustomDataProxy : public QSortFilterProxyModel
{
    Q_OBJECT
public:
    CustomDataProxy(QObject *parent)
      : QSortFilterProxyModel(parent)
    {
    }
 
    //...
 
    QVariant data(const QModelIndex &index, int role) const override
    {
        if (role != Qt::BackgroundRole)
            return QSortFilterProxyModel::data(index, role);
 
        if (m_customData.contains(index.row()))
            return m_customData.value(index.row());
        return QSortFilterProxyModel::data(index, role);
    }
 
private slots:
    void resetInternalData()
    {
        m_customData.clear();
    }
 
private:
  QHash<int, QVariant> m_customData;
};
//! [12]
 
void example(CustomDataProxy *model, const QModelIndex &index)
{
    //! [13]
    QVariant text = model->data(index, Qt::DisplayRole);
    QVariant decoration = model->data(index, Qt::DecorationRole);
    QVariant checkState = model->data(index, Qt::CheckStateRole);
    // etc.
    //! [13]
 
    //! [14]
    std::array<QModelRoleData, 3> roleData = { {
        QModelRoleData(Qt::DisplayRole),
        QModelRoleData(Qt::DecorationRole),
        QModelRoleData(Qt::CheckStateRole)
    } };
 
    // Usually, this is not necessary: A QModelRoleDataSpan
    // will be built automatically for you when passing an array-like
    // container to multiData().
    QModelRoleDataSpan span(roleData);
 
    model->multiData(index, span);
 
    // Use roleData[0].data(), roleData[1].data(), etc.
    //! [14]
}
 
char result = 0;
 
//! [15]
void MyModel::multiData(const QModelIndex &index, QModelRoleDataSpan roleDataSpan) const
{
    for (QModelRoleData &roleData : roleDataSpan) {
        int role = roleData.role();
 
        // ... obtain the data for index and role ...
 
        roleData.setData(result);
    }
}
//! [15]
 
//! [16]
QVariant MyModel::data(const QModelIndex &index, int role) const
{
    QModelRoleData roleData(role);
    multiData(index, roleData);
    return roleData.data();
}
//! [16]