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/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://www.qtsoftware.com/contact.
** $QT_END_LICENSE$
**
****************************************************************************/

/*
  model.cpp

  A simple model that uses a QVector as its data source.
*/

#include "model.h"

/*!
    Returns the number of items in the string list as the number of rows
    in the model.
*/

int LinearModel::rowCount(const QModelIndex &parent) const
{
    Q_USING(parent);

    return values.count();
}

/*
    Returns an appropriate value for the requested data.
    If the view requests an invalid index, an invalid variant is returned.
    If a header is requested then we just return the column or row number,
    depending on the orientation of the header.
    Any valid index that corresponds to a string in the list causes that
    string to be returned.
*/

/*!
    Returns a model index for other component to use when referencing the
    item specified by the given row, column, and type. The parent index
    is ignored.
*/

QModelIndex LinearModel::index(int row, int column, const QModelIndex &parent) const
{
    if (parent == QModelIndex() && row >= 0 && row < rowCount()
        && column == 0)
        return createIndex(row, column, 0);
    else
        return QModelIndex();
}

QVariant LinearModel::data(const QModelIndex &index, int role) const
{
    Q_UNUSED(role);

    if (!index.isValid())
        return QVariant();

    return values.at(index.row());
}

/*!
    Returns Qt::ItemIsEditable so that all items in the vector can be edited.
*/

Qt::ItemFlags LinearModel::flags(const QModelIndex &index) const
{
    // all items in the model are editable
    return QAbstractListModel::flags(index) | Qt::ItemIsEditable;
}

/*!
    Changes an item in the string list, but only if the following conditions
    are met:

    * The index supplied is valid.
    * The index corresponds to an item to be shown in a view.
    * The role associated with editing text is specified.

    The dataChanged() signal is emitted if the item is changed.
*/

bool LinearModel::setData(const QModelIndex &index,
                          const QVariant &value, int role)
{
    if (!index.isValid() || role != Qt::EditRole)
        return false;
    values.replace(index.row(), value.toInt());
    emit dataChanged(index, index);
    return true;
}

/*!
    Inserts a number of rows into the model at the specified position.
*/

bool LinearModel::insertRows(int position, int rows, const QModelIndex &parent)
{
    beginInsertRows(parent, position, position + rows - 1);

    values.insert(position, rows, 0);

    endInsertRows();
    return true;
}

/*!
    Removes a number of rows from the model at the specified position.
*/

bool LinearModel::removeRows(int position, int rows, const QModelIndex &parent)
{
    beginRemoveRows(QModelIndex(), position, position+rows-1);

    values.remove(position, rows);

    endRemoveRows();
    return true;
}