qstringlistmodel.cpp

Go to the documentation of this file.

/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** 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, Digia gives you certain additional
** rights.  These rights are described in the Digia Qt LGPL Exception
** version 1.1, 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.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

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

#include "qstringlistmodel.h"

#ifndef QT_NO_STRINGLISTMODEL

QT_BEGIN_NAMESPACE

QStringListModel::QStringListModel(QObject *parent)
    : QAbstractListModel(parent)
{
}

QStringListModel::QStringListModel(const QStringList &strings, QObject *parent)
    : QAbstractListModel(parent), lst(strings)
{
}

int QStringListModel::rowCount(const QModelIndex &parent) const
{
    if (parent.isValid())
        return 0;

    return lst.count();
}

QVariant QStringListModel::data(const QModelIndex &index, int role) const
{
    if (index.row() < 0 || index.row() >= lst.size())
        return QVariant();

    if (role == Qt::DisplayRole || role == Qt::EditRole)
        return lst.at(index.row());

    return QVariant();
}

Qt::ItemFlags QStringListModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return QAbstractItemModel::flags(index) | Qt::ItemIsDropEnabled;

    return QAbstractItemModel::flags(index) | Qt::ItemIsEditable | Qt::ItemIsDragEnabled | Qt::ItemIsDropEnabled;
}

bool QStringListModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (index.row() >= 0 && index.row() < lst.size()
        && (role == Qt::EditRole || role == Qt::DisplayRole)) {
        lst.replace(index.row(), value.toString());
        emit dataChanged(index, index);
        return true;
    }
    return false;
}

bool QStringListModel::insertRows(int row, int count, const QModelIndex &parent)
{
    if (count < 1 || row < 0 || row > rowCount(parent))
        return false;

    beginInsertRows(QModelIndex(), row, row + count - 1);

    for (int r = 0; r < count; ++r)
        lst.insert(row, QString());

    endInsertRows();

    return true;
}

bool QStringListModel::removeRows(int row, int count, const QModelIndex &parent)
{
    if (count <= 0 || row < 0 || (row + count) > rowCount(parent))
        return false;

    beginRemoveRows(QModelIndex(), row, row + count - 1);

    for (int r = 0; r < count; ++r)
        lst.removeAt(row);

    endRemoveRows();

    return true;
}

static bool ascendingLessThan(const QPair<QString, int> &s1, const QPair<QString, int> &s2)
{
    return s1.first < s2.first;
}

static bool decendingLessThan(const QPair<QString, int> &s1, const QPair<QString, int> &s2)
{
    return s1.first > s2.first;
}

void QStringListModel::sort(int, Qt::SortOrder order)
{
    emit layoutAboutToBeChanged();

    QList<QPair<QString, int> > list;
    for (int i = 0; i < lst.count(); ++i)
        list.append(QPair<QString, int>(lst.at(i), i));

    if (order == Qt::AscendingOrder)
        qSort(list.begin(), list.end(), ascendingLessThan);
    else
        qSort(list.begin(), list.end(), decendingLessThan);

    lst.clear();
    QVector<int> forwarding(list.count());
    for (int i = 0; i < list.count(); ++i) {
        lst.append(list.at(i).first);
        forwarding[list.at(i).second] = i;
    }

    QModelIndexList oldList = persistentIndexList();
    QModelIndexList newList;
    for (int i = 0; i < oldList.count(); ++i)
        newList.append(index(forwarding.at(oldList.at(i).row()), 0));
    changePersistentIndexList(oldList, newList);

    emit layoutChanged();
}

QStringList QStringListModel::stringList() const
{
    return lst;
}

void QStringListModel::setStringList(const QStringList &strings)
{
    emit beginResetModel();
    lst = strings;
    emit endResetModel();
}

Qt::DropActions QStringListModel::supportedDropActions() const
{
    return QAbstractItemModel::supportedDropActions() | Qt::MoveAction;
}

QT_END_NAMESPACE

#endif // QT_NO_STRINGLISTMODEL