diff -r 000000000000 -r 1918ee327afb examples/tools/contiguouscache/randomlistmodel.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/tools/contiguouscache/randomlistmodel.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,97 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples 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 Technology Preview License Agreement accompanying
+** this package.
+**
+** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include "randomlistmodel.h"
+#include <stdlib.h>
+
+static const int bufferSize(500);
+static const int lookAhead(100);
+static const int halfLookAhead(lookAhead/2);
+
+RandomListModel::RandomListModel(QObject *parent)
+: QAbstractListModel(parent), m_rows(bufferSize), m_count(10000)
+{
+}
+
+RandomListModel::~RandomListModel()
+{
+}
+
+int RandomListModel::rowCount(const QModelIndex &) const
+{
+    return m_count;
+}
+
+//! [0]
+QVariant RandomListModel::data(const QModelIndex &index, int role) const
+{
+    if (role != Qt::DisplayRole)
+        return QVariant();
+
+    int row = index.row();
+
+    if (row > m_rows.lastIndex()) {
+        if (row - m_rows.lastIndex() > lookAhead)
+            cacheRows(row-halfLookAhead, qMin(m_count, row+halfLookAhead));
+        else while (row > m_rows.lastIndex())
+            m_rows.append(fetchRow(m_rows.lastIndex()+1));
+    } else if (row < m_rows.firstIndex()) {
+        if (m_rows.firstIndex() - row > lookAhead)
+            cacheRows(qMax(0, row-halfLookAhead), row+halfLookAhead);
+        else while (row < m_rows.firstIndex())
+            m_rows.prepend(fetchRow(m_rows.firstIndex()-1));
+    }
+
+    return m_rows.at(row);
+}
+
+void RandomListModel::cacheRows(int from, int to) const
+{
+    for (int i = from; i <= to; ++i)
+        m_rows.insert(i, fetchRow(i));
+}
+//![0]
+
+//![1]
+QString RandomListModel::fetchRow(int position) const
+{
+    return QString::number(rand() % ++position);
+}
+//![1]