Initial import from the monolithic Qt.

This is the beginning of revision history for this module. If you
want to look at revision history older than this, please refer to the
Qt Git wiki for how to use Git history grafting. At the time of
writing, this wiki is located here:

http://qt.gitorious.org/qt/pages/GitIntroductionWithQt

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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

26 files changed, 1811 insertions, 0 deletions

diff --git a/demos/undo/commands.cpp b/demos/undo/commands.cpp
new file mode 100644
index 0000000000..82117d597d
--- /dev/null
+++ b/demos/undo/commands.cpp
@@ -0,0 +1,180 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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 "commands.h"
+
+static const int setShapeRectCommandId = 1;
+static const int setShapeColorCommandId = 2;
+
+/******************************************************************************
+** AddShapeCommand
+*/
+
+AddShapeCommand::AddShapeCommand(Document *doc, const Shape &shape, QUndoCommand *parent)
+    : QUndoCommand(parent)
+{
+    m_doc = doc;
+    m_shape = shape;
+}
+
+void AddShapeCommand::undo()
+{
+    m_doc->deleteShape(m_shapeName);
+}
+
+void AddShapeCommand::redo()
+{
+    // A shape only gets a name when it is inserted into a document
+    m_shapeName = m_doc->addShape(m_shape);
+    setText(QObject::tr("Add %1").arg(m_shapeName));
+}
+
+/******************************************************************************
+** RemoveShapeCommand
+*/
+
+RemoveShapeCommand::RemoveShapeCommand(Document *doc, const QString &shapeName,
+                                        QUndoCommand *parent)
+    : QUndoCommand(parent)
+{
+    setText(QObject::tr("Remove %1").arg(shapeName));
+    m_doc = doc;
+    m_shape = doc->shape(shapeName);
+    m_shapeName = shapeName;
+}
+
+void RemoveShapeCommand::undo()
+{
+    m_shapeName = m_doc->addShape(m_shape);
+}
+
+void RemoveShapeCommand::redo()
+{
+    m_doc->deleteShape(m_shapeName);
+}
+
+/******************************************************************************
+** SetShapeColorCommand
+*/
+
+SetShapeColorCommand::SetShapeColorCommand(Document *doc, const QString &shapeName,
+                                            const QColor &color, QUndoCommand *parent)
+    : QUndoCommand(parent)
+{
+    setText(QObject::tr("Set %1's color").arg(shapeName));
+
+    m_doc = doc;
+    m_shapeName = shapeName;
+    m_oldColor = doc->shape(shapeName).color();
+    m_newColor = color;
+}
+
+void SetShapeColorCommand::undo()
+{
+    m_doc->setShapeColor(m_shapeName, m_oldColor);
+}
+
+void SetShapeColorCommand::redo()
+{
+    m_doc->setShapeColor(m_shapeName, m_newColor);
+}
+
+bool SetShapeColorCommand::mergeWith(const QUndoCommand *command)
+{
+    if (command->id() != setShapeColorCommandId)
+        return false;
+
+    const SetShapeColorCommand *other = static_cast<const SetShapeColorCommand*>(command);
+    if (m_shapeName != other->m_shapeName)
+        return false;
+
+    m_newColor = other->m_newColor;
+    return true;
+}
+
+int SetShapeColorCommand::id() const
+{
+    return setShapeColorCommandId;
+}
+
+/******************************************************************************
+** SetShapeRectCommand
+*/
+
+SetShapeRectCommand::SetShapeRectCommand(Document *doc, const QString &shapeName,
+                                            const QRect &rect, QUndoCommand *parent)
+    : QUndoCommand(parent)
+{
+    setText(QObject::tr("Change %1's geometry").arg(shapeName));
+
+    m_doc = doc;
+    m_shapeName = shapeName;
+    m_oldRect = doc->shape(shapeName).rect();
+    m_newRect = rect;
+}
+
+void SetShapeRectCommand::undo()
+{
+    m_doc->setShapeRect(m_shapeName, m_oldRect);
+}
+
+void SetShapeRectCommand::redo()
+{
+    m_doc->setShapeRect(m_shapeName, m_newRect);
+}
+
+bool SetShapeRectCommand::mergeWith(const QUndoCommand *command)
+{
+    if (command->id() != setShapeRectCommandId)
+        return false;
+
+    const SetShapeRectCommand *other = static_cast<const SetShapeRectCommand*>(command);
+    if (m_shapeName != other->m_shapeName)
+        return false;
+
+    m_newRect = other->m_newRect;
+    return true;
+}
+
+int SetShapeRectCommand::id() const
+{
+    return setShapeRectCommandId;
+}
diff --git a/demos/undo/commands.h b/demos/undo/commands.h
new file mode 100644
index 0000000000..60cf061598
--- /dev/null
+++ b/demos/undo/commands.h
@@ -0,0 +1,112 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef COMMANDS_H
+#define COMMANDS_H
+
+#include <QUndoCommand>
+#include "document.h"
+
+class AddShapeCommand : public QUndoCommand
+{
+public:
+    AddShapeCommand(Document *doc, const Shape &shape, QUndoCommand *parent = 0);
+    void undo();
+    void redo();
+
+private:
+    Document *m_doc;
+    Shape m_shape;
+    QString m_shapeName;
+};
+
+class RemoveShapeCommand : public QUndoCommand
+{
+public:
+    RemoveShapeCommand(Document *doc, const QString &shapeName, QUndoCommand *parent = 0);
+    void undo();
+    void redo();
+
+private:
+    Document *m_doc;
+    Shape m_shape;
+    QString m_shapeName;
+};
+
+class SetShapeColorCommand : public QUndoCommand
+{
+public:
+    SetShapeColorCommand(Document *doc, const QString &shapeName, const QColor &color,
+                            QUndoCommand *parent = 0);
+
+    void undo();
+    void redo();
+
+    bool mergeWith(const QUndoCommand *command);
+    int id() const;
+
+private:
+    Document *m_doc;
+    QString m_shapeName;
+    QColor m_oldColor;
+    QColor m_newColor;
+};
+
+class SetShapeRectCommand : public QUndoCommand
+{
+public:
+    SetShapeRectCommand(Document *doc, const QString &shapeName, const QRect &rect,
+                            QUndoCommand *parent = 0);
+
+    void undo();
+    void redo();
+
+    bool mergeWith(const QUndoCommand *command);
+    int id() const;
+
+private:
+    Document *m_doc;
+    QString m_shapeName;
+    QRect m_oldRect;
+    QRect m_newRect;
+};
+
+#endif // COMMANDS_H
diff --git a/demos/undo/document.cpp b/demos/undo/document.cpp
new file mode 100644
index 0000000000..73187af526
--- /dev/null
+++ b/demos/undo/document.cpp
@@ -0,0 +1,445 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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 <qevent.h>
+#include <QPainter>
+#include <QTextStream>
+#include <QUndoStack>
+#include "document.h"
+#include "commands.h"
+
+static const int resizeHandleWidth = 6;
+
+/******************************************************************************
+** Shape
+*/
+
+const QSize Shape::minSize(80, 50);
+
+Shape::Shape(Type type, const QColor &color, const QRect &rect)
+    : m_type(type), m_rect(rect), m_color(color)
+{
+}
+
+Shape::Type Shape::type() const
+{
+    return m_type;
+}
+
+QRect Shape::rect() const
+{
+    return m_rect;
+}
+
+QColor Shape::color() const
+{
+    return m_color;
+}
+
+QString Shape::name() const
+{
+    return m_name;
+}
+
+QRect Shape::resizeHandle() const
+{
+    QPoint br = m_rect.bottomRight();
+    return QRect(br - QPoint(resizeHandleWidth, resizeHandleWidth), br);
+}
+
+QString Shape::typeToString(Type type)
+{
+    QString result;
+
+    switch (type) {
+        case Rectangle:
+            result = QLatin1String("Rectangle");
+            break;
+        case Circle:
+            result = QLatin1String("Circle");
+            break;
+        case Triangle:
+            result = QLatin1String("Triangle");
+            break;
+    }
+
+    return result;
+}
+
+Shape::Type Shape::stringToType(const QString &s, bool *ok)
+{
+    if (ok != 0)
+        *ok = true;
+
+    if (s == QLatin1String("Rectangle"))
+        return Rectangle;
+    if (s == QLatin1String("Circle"))
+        return Circle;
+    if (s == QLatin1String("Triangle"))
+        return Triangle;
+
+    if (ok != 0)
+        *ok = false;
+    return Rectangle;
+}
+
+/******************************************************************************
+** Document
+*/
+
+Document::Document(QWidget *parent)
+    : QWidget(parent), m_currentIndex(-1), m_mousePressIndex(-1), m_resizeHandlePressed(false)
+{
+    m_undoStack = new QUndoStack(this);
+
+    setAutoFillBackground(true);
+    setBackgroundRole(QPalette::Base);
+
+    QPalette pal = palette();
+    pal.setBrush(QPalette::Base, QPixmap(":/icons/background.png"));
+    pal.setColor(QPalette::HighlightedText, Qt::red);
+    setPalette(pal);
+}
+
+QString Document::addShape(const Shape &shape)
+{
+    QString name = Shape::typeToString(shape.type());
+    name = uniqueName(name);
+
+    m_shapeList.append(shape);
+    m_shapeList[m_shapeList.count() - 1].m_name = name;
+    setCurrentShape(m_shapeList.count() - 1);
+
+    return name;
+}
+
+void Document::deleteShape(const QString &shapeName)
+{
+    int index = indexOf(shapeName);
+    if (index == -1)
+        return;
+
+    update(m_shapeList.at(index).rect());
+
+    m_shapeList.removeAt(index);
+
+    if (index <= m_currentIndex) {
+        m_currentIndex = -1;
+        if (index == m_shapeList.count())
+            --index;
+        setCurrentShape(index);
+    }
+}
+
+Shape Document::shape(const QString &shapeName) const
+{
+    int index = indexOf(shapeName);
+    if (index == -1)
+        return Shape();
+    return m_shapeList.at(index);
+}
+
+void Document::setShapeRect(const QString &shapeName, const QRect &rect)
+{
+    int index = indexOf(shapeName);
+    if (index == -1)
+        return;
+
+    Shape &shape = m_shapeList[index];
+
+    update(shape.rect());
+    update(rect);
+
+    shape.m_rect = rect;
+}
+
+void Document::setShapeColor(const QString &shapeName, const QColor &color)
+{
+
+    int index = indexOf(shapeName);
+    if (index == -1)
+        return;
+
+    Shape &shape = m_shapeList[index];
+    shape.m_color = color;
+
+    update(shape.rect());
+}
+
+QUndoStack *Document::undoStack() const
+{
+    return m_undoStack;
+}
+
+bool Document::load(QTextStream &stream)
+{
+    m_shapeList.clear();
+
+    while (!stream.atEnd()) {
+        QString shapeType, shapeName, colorName;
+        int left, top, width, height;
+        stream >> shapeType >> shapeName >> colorName >> left >> top >> width >> height;
+        if (stream.status() != QTextStream::Ok)
+            return false;
+        bool ok;
+        Shape::Type type = Shape::stringToType(shapeType, &ok);
+        if (!ok)
+            return false;
+        QColor color(colorName);
+        if (!color.isValid())
+            return false;
+
+        Shape shape(type);
+        shape.m_name = shapeName;
+        shape.m_color = color;
+        shape.m_rect = QRect(left, top, width, height);
+
+        m_shapeList.append(shape);
+    }
+
+    m_currentIndex = m_shapeList.isEmpty() ? -1 : 0;
+
+    return true;
+}
+
+void Document::save(QTextStream &stream)
+{
+    for (int i = 0; i < m_shapeList.count(); ++i) {
+        const Shape &shape = m_shapeList.at(i);
+        QRect r = shape.rect();
+        stream << Shape::typeToString(shape.type()) << QLatin1Char(' ')
+                << shape.name() << QLatin1Char(' ')
+                << shape.color().name() << QLatin1Char(' ')
+                << r.left() << QLatin1Char(' ')
+                << r.top() << QLatin1Char(' ')
+                << r.width() << QLatin1Char(' ')
+                << r.height();
+        if (i != m_shapeList.count() - 1)
+            stream << QLatin1Char('\n');
+    }
+    m_undoStack->setClean();
+}
+
+QString Document::fileName() const
+{
+    return m_fileName;
+}
+
+void Document::setFileName(const QString &fileName)
+{
+    m_fileName = fileName;
+}
+
+int Document::indexAt(const QPoint &pos) const
+{
+    for (int i = m_shapeList.count() - 1; i >= 0; --i) {
+        if (m_shapeList.at(i).rect().contains(pos))
+            return i;
+    }
+    return -1;
+}
+
+void Document::mousePressEvent(QMouseEvent *event)
+{
+    event->accept();
+    int index = indexAt(event->pos());;
+    if (index != -1) {
+        setCurrentShape(index);
+
+        const Shape &shape = m_shapeList.at(index);
+        m_resizeHandlePressed = shape.resizeHandle().contains(event->pos());
+
+        if (m_resizeHandlePressed)
+            m_mousePressOffset = shape.rect().bottomRight() - event->pos();
+        else
+            m_mousePressOffset = event->pos() - shape.rect().topLeft();
+    }
+    m_mousePressIndex = index;
+}
+
+void Document::mouseReleaseEvent(QMouseEvent *event)
+{
+    event->accept();
+    m_mousePressIndex = -1;
+}
+
+void Document::mouseMoveEvent(QMouseEvent *event)
+{
+    event->accept();
+
+    if (m_mousePressIndex == -1)
+        return;
+
+    const Shape &shape = m_shapeList.at(m_mousePressIndex);
+
+    QRect rect;
+    if (m_resizeHandlePressed) {
+        rect = QRect(shape.rect().topLeft(), event->pos() + m_mousePressOffset);
+    } else {
+        rect = shape.rect();
+        rect.moveTopLeft(event->pos() - m_mousePressOffset);
+    }
+
+    QSize size = rect.size().expandedTo(Shape::minSize);
+    rect.setSize(size);
+
+    m_undoStack->push(new SetShapeRectCommand(this, shape.name(), rect));
+}
+
+static QGradient gradient(const QColor &color, const QRect &rect)
+{
+    QColor c = color;
+    c.setAlpha(160);
+    QLinearGradient result(rect.topLeft(), rect.bottomRight());
+    result.setColorAt(0, c.dark(150));
+    result.setColorAt(0.5, c.light(200));
+    result.setColorAt(1, c.dark(150));
+    return result;
+}
+
+static QPolygon triangle(const QRect &rect)
+{
+    QPolygon result(3);
+    result.setPoint(0, rect.center().x(), rect.top());
+    result.setPoint(1, rect.right(), rect.bottom());
+    result.setPoint(2, rect.left(), rect.bottom());
+    return result;
+}
+
+void Document::paintEvent(QPaintEvent *event)
+{
+    QRegion paintRegion = event->region();
+    QPainter painter(this);
+    QPalette pal = palette();
+
+    for (int i = 0; i < m_shapeList.count(); ++i) {
+        const Shape &shape = m_shapeList.at(i);
+
+        if (!paintRegion.contains(shape.rect()))
+            continue;
+
+        QPen pen = pal.text().color();
+        pen.setWidth(i == m_currentIndex ? 2 : 1);
+        painter.setPen(pen);
+        painter.setBrush(gradient(shape.color(), shape.rect()));
+
+        QRect rect = shape.rect();
+        rect.adjust(1, 1, -resizeHandleWidth/2, -resizeHandleWidth/2);
+
+        // paint the shape
+        switch (shape.type()) {
+            case Shape::Rectangle:
+                painter.drawRect(rect);
+                break;
+            case Shape::Circle:
+                painter.setRenderHint(QPainter::Antialiasing);
+                painter.drawEllipse(rect);
+                painter.setRenderHint(QPainter::Antialiasing, false);
+                break;
+            case Shape::Triangle:
+                painter.setRenderHint(QPainter::Antialiasing);
+                painter.drawPolygon(triangle(rect));
+                painter.setRenderHint(QPainter::Antialiasing, false);
+                break;
+        }
+
+        // paint the resize handle
+        painter.setPen(pal.text().color());
+        painter.setBrush(Qt::white);
+        painter.drawRect(shape.resizeHandle().adjusted(0, 0, -1, -1));
+
+        // paint the shape name
+        painter.setBrush(pal.text());
+        if (shape.type() == Shape::Triangle)
+            rect.adjust(0, rect.height()/2, 0, 0);
+        painter.drawText(rect, Qt::AlignCenter, shape.name());
+    }
+}
+
+void Document::setCurrentShape(int index)
+{
+    QString currentName;
+
+    if (m_currentIndex != -1)
+        update(m_shapeList.at(m_currentIndex).rect());
+
+    m_currentIndex = index;
+
+    if (m_currentIndex != -1) {
+        const Shape &current = m_shapeList.at(m_currentIndex);
+        update(current.rect());
+        currentName = current.name();
+    }
+
+    emit currentShapeChanged(currentName);
+}
+
+int Document::indexOf(const QString &shapeName) const
+{
+    for (int i = 0; i < m_shapeList.count(); ++i) {
+        if (m_shapeList.at(i).name() == shapeName)
+            return i;
+    }
+    return -1;
+}
+
+QString Document::uniqueName(const QString &name) const
+{
+    QString unique;
+
+    for (int i = 0; ; ++i) {
+        unique = name;
+        if (i > 0)
+            unique += QString::number(i);
+        if (indexOf(unique) == -1)
+            break;
+    }
+
+    return unique;
+}
+
+QString Document::currentShapeName() const
+{
+    if (m_currentIndex == -1)
+        return QString();
+    return m_shapeList.at(m_currentIndex).name();
+}
+
diff --git a/demos/undo/document.h b/demos/undo/document.h
new file mode 100644
index 0000000000..c85e6dd0a5
--- /dev/null
+++ b/demos/undo/document.h
@@ -0,0 +1,125 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef DOCUMENT_H
+#define DOCUMENT_H
+
+#include <QWidget>
+
+QT_FORWARD_DECLARE_CLASS(QUndoStack)
+QT_FORWARD_DECLARE_CLASS(QTextStream)
+
+class Shape
+{
+public:
+    enum Type { Rectangle, Circle, Triangle };
+
+    Shape(Type type = Rectangle, const QColor &color = Qt::red, const QRect &rect = QRect());
+
+    Type type() const;
+    QString name() const;
+    QRect rect() const;
+    QRect resizeHandle() const;
+    QColor color() const;
+
+    static QString typeToString(Type type);
+    static Type stringToType(const QString &s, bool *ok = 0);
+
+    static const QSize minSize;
+
+private:
+    Type m_type;
+    QRect m_rect;
+    QColor m_color;
+    QString m_name;
+
+    friend class Document;
+};
+
+class Document : public QWidget
+{
+    Q_OBJECT
+
+public:
+    Document(QWidget *parent = 0);
+
+    QString addShape(const Shape &shape);
+    void deleteShape(const QString &shapeName);
+    Shape shape(const QString &shapeName) const;
+    QString currentShapeName() const;
+
+    void setShapeRect(const QString &shapeName, const QRect &rect);
+    void setShapeColor(const QString &shapeName, const QColor &color);
+
+    bool load(QTextStream &stream);
+    void save(QTextStream &stream);
+
+    QString fileName() const;
+    void setFileName(const QString &fileName);
+
+    QUndoStack *undoStack() const;
+
+signals:
+    void currentShapeChanged(const QString &shapeName);
+
+protected:
+    void paintEvent(QPaintEvent *event);
+    void mousePressEvent(QMouseEvent *event);
+    void mouseReleaseEvent(QMouseEvent *event);
+    void mouseMoveEvent(QMouseEvent *event);
+
+private:
+    void setCurrentShape(int index);
+    int indexOf(const QString &shapeName) const;
+    int indexAt(const QPoint &pos) const;
+    QString uniqueName(const QString &name) const;
+
+    QList<Shape> m_shapeList;
+    int m_currentIndex;
+    int m_mousePressIndex;
+    QPoint m_mousePressOffset;
+    bool m_resizeHandlePressed;
+    QString m_fileName;
+
+    QUndoStack *m_undoStack;
+};
+
+#endif // DOCUMENT_H
diff --git a/demos/undo/icons/background.png b/demos/undo/icons/background.png
new file mode 100644
index 0000000000..3bc5ed8cf0
--- /dev/null
+++ b/demos/undo/icons/background.png
diff --git a/demos/undo/icons/blue.png b/demos/undo/icons/blue.png
new file mode 100644
index 0000000000..4e181bb61a
--- /dev/null
+++ b/demos/undo/icons/blue.png
diff --git a/demos/undo/icons/circle.png b/demos/undo/icons/circle.png
new file mode 100644
index 0000000000..ed16c6e144
--- /dev/null
+++ b/demos/undo/icons/circle.png
diff --git a/demos/undo/icons/exit.png b/demos/undo/icons/exit.png
new file mode 100644
index 0000000000..539cb2ead9
--- /dev/null
+++ b/demos/undo/icons/exit.png
diff --git a/demos/undo/icons/fileclose.png b/demos/undo/icons/fileclose.png
new file mode 100644
index 0000000000..c5483d14ab
--- /dev/null
+++ b/demos/undo/icons/fileclose.png
diff --git a/demos/undo/icons/filenew.png b/demos/undo/icons/filenew.png
new file mode 100644
index 0000000000..57e57e343b
--- /dev/null
+++ b/demos/undo/icons/filenew.png
diff --git a/demos/undo/icons/fileopen.png b/demos/undo/icons/fileopen.png
new file mode 100644
index 0000000000..33e0d6394c
--- /dev/null
+++ b/demos/undo/icons/fileopen.png
diff --git a/demos/undo/icons/filesave.png b/demos/undo/icons/filesave.png
new file mode 100644
index 0000000000..57fd5e2f34
--- /dev/null
+++ b/demos/undo/icons/filesave.png
diff --git a/demos/undo/icons/green.png b/demos/undo/icons/green.png
new file mode 100644
index 0000000000..e2e7cc9e50
--- /dev/null
+++ b/demos/undo/icons/green.png
diff --git a/demos/undo/icons/ok.png b/demos/undo/icons/ok.png
new file mode 100644
index 0000000000..e355ea91bc
--- /dev/null
+++ b/demos/undo/icons/ok.png
diff --git a/demos/undo/icons/rectangle.png b/demos/undo/icons/rectangle.png
new file mode 100644
index 0000000000..3a7d9795fd
--- /dev/null
+++ b/demos/undo/icons/rectangle.png
diff --git a/demos/undo/icons/red.png b/demos/undo/icons/red.png
new file mode 100644
index 0000000000..58c3e7253b
--- /dev/null
+++ b/demos/undo/icons/red.png
diff --git a/demos/undo/icons/redo.png b/demos/undo/icons/redo.png
new file mode 100644
index 0000000000..5591517e1c
--- /dev/null
+++ b/demos/undo/icons/redo.png
diff --git a/demos/undo/icons/remove.png b/demos/undo/icons/remove.png
new file mode 100644
index 0000000000..7a7b048c0a
--- /dev/null
+++ b/demos/undo/icons/remove.png
diff --git a/demos/undo/icons/triangle.png b/demos/undo/icons/triangle.png
new file mode 100644
index 0000000000..2969131c31
--- /dev/null
+++ b/demos/undo/icons/triangle.png
diff --git a/demos/undo/icons/undo.png b/demos/undo/icons/undo.png
new file mode 100644
index 0000000000..8cf63a8ec9
--- /dev/null
+++ b/demos/undo/icons/undo.png
diff --git a/demos/undo/main.cpp b/demos/undo/main.cpp
new file mode 100644
index 0000000000..ef11dc51c1
--- /dev/null
+++ b/demos/undo/main.cpp
@@ -0,0 +1,56 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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 <QApplication>
+#include "mainwindow.h"
+
+int main(int argc, char **argv)
+{
+    Q_INIT_RESOURCE(undo);
+
+    QApplication app(argc, argv);
+
+    MainWindow win;
+    win.resize(800, 600);
+    win.show();
+
+    return app.exec();
+};
diff --git a/demos/undo/mainwindow.cpp b/demos/undo/mainwindow.cpp
new file mode 100644
index 0000000000..3dca63143f
--- /dev/null
+++ b/demos/undo/mainwindow.cpp
@@ -0,0 +1,446 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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 <QUndoGroup>
+#include <QUndoStack>
+#include <QFileDialog>
+#include <QMessageBox>
+#include <QTextStream>
+#include <QToolButton>
+#include "document.h"
+#include "mainwindow.h"
+#include "commands.h"
+
+MainWindow::MainWindow(QWidget *parent)
+    : QMainWindow(parent)
+{
+    setupUi(this);
+
+    QWidget *w = documentTabs->widget(0);
+    documentTabs->removeTab(0);
+    delete w;
+
+    connect(actionOpen, SIGNAL(triggered()), this, SLOT(openDocument()));
+    connect(actionClose, SIGNAL(triggered()), this, SLOT(closeDocument()));
+    connect(actionNew, SIGNAL(triggered()), this, SLOT(newDocument()));
+    connect(actionSave, SIGNAL(triggered()), this, SLOT(saveDocument()));
+    connect(actionExit, SIGNAL(triggered()), this, SLOT(close()));
+    connect(actionRed, SIGNAL(triggered()), this, SLOT(setShapeColor()));
+    connect(actionGreen, SIGNAL(triggered()), this, SLOT(setShapeColor()));
+    connect(actionBlue, SIGNAL(triggered()), this, SLOT(setShapeColor()));
+    connect(actionAddCircle, SIGNAL(triggered()), this, SLOT(addShape()));
+    connect(actionAddRectangle, SIGNAL(triggered()), this, SLOT(addShape()));
+    connect(actionAddTriangle, SIGNAL(triggered()), this, SLOT(addShape()));
+    connect(actionRemoveShape, SIGNAL(triggered()), this, SLOT(removeShape()));
+    connect(actionAddRobot, SIGNAL(triggered()), this, SLOT(addRobot()));
+    connect(actionAddSnowman, SIGNAL(triggered()), this, SLOT(addSnowman()));
+    connect(actionAbout, SIGNAL(triggered()), this, SLOT(about()));
+    connect(actionAboutQt, SIGNAL(triggered()), this, SLOT(aboutQt()));
+
+    connect(undoLimit, SIGNAL(valueChanged(int)), this, SLOT(updateActions()));
+    connect(documentTabs, SIGNAL(currentChanged(int)), this, SLOT(updateActions()));
+
+    actionOpen->setShortcut(QString("Ctrl+O"));
+    actionClose->setShortcut(QString("Ctrl+W"));
+    actionNew->setShortcut(QString("Ctrl+N"));
+    actionSave->setShortcut(QString("Ctrl+S"));
+    actionExit->setShortcut(QString("Ctrl+Q"));
+    actionRemoveShape->setShortcut(QString("Del"));
+    actionRed->setShortcut(QString("Alt+R"));
+    actionGreen->setShortcut(QString("Alt+G"));
+    actionBlue->setShortcut(QString("Alt+B"));
+    actionAddCircle->setShortcut(QString("Alt+C"));
+    actionAddRectangle->setShortcut(QString("Alt+L"));
+    actionAddTriangle->setShortcut(QString("Alt+T"));
+
+    m_undoGroup = new QUndoGroup(this);
+    undoView->setGroup(m_undoGroup);
+    undoView->setCleanIcon(QIcon(":/icons/ok.png"));
+
+    QAction *undoAction = m_undoGroup->createUndoAction(this);
+    QAction *redoAction = m_undoGroup->createRedoAction(this);
+    undoAction->setIcon(QIcon(":/icons/undo.png"));
+    redoAction->setIcon(QIcon(":/icons/redo.png"));
+    menuShape->insertAction(menuShape->actions().at(0), undoAction);
+    menuShape->insertAction(undoAction, redoAction);
+
+    toolBar->addAction(undoAction);
+    toolBar->addAction(redoAction);
+
+    newDocument();
+    updateActions();
+};
+
+void MainWindow::updateActions()
+{
+    Document *doc = currentDocument();
+    m_undoGroup->setActiveStack(doc == 0 ? 0 : doc->undoStack());
+    QString shapeName = doc == 0 ? QString() : doc->currentShapeName();
+
+    actionAddRobot->setEnabled(doc != 0);
+    actionAddSnowman->setEnabled(doc != 0);
+    actionAddCircle->setEnabled(doc != 0);
+    actionAddRectangle->setEnabled(doc != 0);
+    actionAddTriangle->setEnabled(doc != 0);
+    actionClose->setEnabled(doc != 0);
+    actionSave->setEnabled(doc != 0 && !doc->undoStack()->isClean());
+    undoLimit->setEnabled(doc != 0 && doc->undoStack()->count() == 0);
+
+    if (shapeName.isEmpty()) {
+        actionRed->setEnabled(false);
+        actionGreen->setEnabled(false);
+        actionBlue->setEnabled(false);
+        actionRemoveShape->setEnabled(false);
+    } else {
+        Shape shape = doc->shape(shapeName);
+        actionRed->setEnabled(shape.color() != Qt::red);
+        actionGreen->setEnabled(shape.color() != Qt::green);
+        actionBlue->setEnabled(shape.color() != Qt::blue);
+        actionRemoveShape->setEnabled(true);
+    }
+
+    if (doc != 0) {
+        int index = documentTabs->indexOf(doc);
+        Q_ASSERT(index != -1);
+        static const QIcon unsavedIcon(":/icons/filesave.png");
+        documentTabs->setTabIcon(index, doc->undoStack()->isClean() ? QIcon() : unsavedIcon);
+
+        if (doc->undoStack()->count() == 0)
+            doc->undoStack()->setUndoLimit(undoLimit->value());
+    }
+}
+
+void MainWindow::openDocument()
+{
+    QString fileName = QFileDialog::getOpenFileName(this);
+    if (fileName.isEmpty())
+        return;
+
+    QFile file(fileName);
+    if (!file.open(QIODevice::ReadOnly)) {
+        QMessageBox::warning(this,
+                            tr("File error"),
+                            tr("Failed to open\n%1").arg(fileName));
+        return;
+    }
+    QTextStream stream(&file);
+
+    Document *doc = new Document();
+    if (!doc->load(stream)) {
+        QMessageBox::warning(this,
+                            tr("Parse error"),
+                            tr("Failed to parse\n%1").arg(fileName));
+        delete doc;
+        return;
+    }
+
+    doc->setFileName(fileName);
+    addDocument(doc);
+}
+
+QString MainWindow::fixedWindowTitle(const Document *doc) const
+{
+    QString title = doc->fileName();
+
+    if (title.isEmpty())
+        title = tr("Unnamed");
+    else
+        title = QFileInfo(title).fileName();
+
+    QString result;
+
+    for (int i = 0; ; ++i) {
+        result = title;
+        if (i > 0)
+            result += QString::number(i);
+
+        bool unique = true;
+        for (int j = 0; j < documentTabs->count(); ++j) {
+            const QWidget *widget = documentTabs->widget(j);
+            if (widget == doc)
+                continue;
+            if (result == documentTabs->tabText(j)) {
+                unique = false;
+                break;
+            }
+        }
+
+        if (unique)
+            break;
+    }
+
+    return result;
+}
+
+void MainWindow::addDocument(Document *doc)
+{
+    if (documentTabs->indexOf(doc) != -1)
+        return;
+    m_undoGroup->addStack(doc->undoStack());
+    documentTabs->addTab(doc, fixedWindowTitle(doc));
+    connect(doc, SIGNAL(currentShapeChanged(QString)), this, SLOT(updateActions()));
+    connect(doc->undoStack(), SIGNAL(indexChanged(int)), this, SLOT(updateActions()));
+    connect(doc->undoStack(), SIGNAL(cleanChanged(bool)), this, SLOT(updateActions()));
+
+    setCurrentDocument(doc);
+}
+
+void MainWindow::setCurrentDocument(Document *doc)
+{
+    documentTabs->setCurrentWidget(doc);
+}
+
+Document *MainWindow::currentDocument() const
+{
+    return qobject_cast<Document*>(documentTabs->currentWidget());
+}
+
+void MainWindow::removeDocument(Document *doc)
+{
+    int index = documentTabs->indexOf(doc);
+    if (index == -1)
+        return;
+
+    documentTabs->removeTab(index);
+    m_undoGroup->removeStack(doc->undoStack());
+    disconnect(doc, SIGNAL(currentShapeChanged(QString)), this, SLOT(updateActions()));
+    disconnect(doc->undoStack(), SIGNAL(indexChanged(int)), this, SLOT(updateActions()));
+    disconnect(doc->undoStack(), SIGNAL(cleanChanged(bool)), this, SLOT(updateActions()));
+
+    if (documentTabs->count() == 0) {
+        newDocument();
+        updateActions();
+    }
+}
+
+void MainWindow::saveDocument()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    for (;;) {
+        QString fileName = doc->fileName();
+
+        if (fileName.isEmpty())
+            fileName = QFileDialog::getSaveFileName(this);
+        if (fileName.isEmpty())
+            break;
+
+        QFile file(fileName);
+        if (!file.open(QIODevice::WriteOnly)) {
+            QMessageBox::warning(this,
+                                tr("File error"),
+                                tr("Failed to open\n%1").arg(fileName));
+            doc->setFileName(QString());
+        } else {
+            QTextStream stream(&file);
+            doc->save(stream);
+            doc->setFileName(fileName);
+
+            int index = documentTabs->indexOf(doc);
+            Q_ASSERT(index != -1);
+            documentTabs->setTabText(index, fixedWindowTitle(doc));
+
+            break;
+        }
+    }
+}
+
+void MainWindow::closeDocument()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    if (!doc->undoStack()->isClean()) {
+        int button
+            = QMessageBox::warning(this,
+                            tr("Unsaved changes"),
+                            tr("Would you like to save this document?"),
+                            QMessageBox::Yes, QMessageBox::No);
+        if (button == QMessageBox::Yes)
+            saveDocument();
+    }
+
+    removeDocument(doc);
+    delete doc;
+}
+
+void MainWindow::newDocument()
+{
+    addDocument(new Document());
+}
+
+static QColor randomColor()
+{
+    int r = (int) (3.0*(rand()/(RAND_MAX + 1.0)));
+    switch (r) {
+        case 0:
+            return Qt::red;
+        case 1:
+            return Qt::green;
+        default:
+            break;
+    }
+    return Qt::blue;
+}
+
+static QRect randomRect(const QSize &s)
+{
+    QSize min = Shape::minSize;
+
+    int left = (int) ((0.0 + s.width() - min.width())*(rand()/(RAND_MAX + 1.0)));
+    int top = (int) ((0.0 + s.height() - min.height())*(rand()/(RAND_MAX + 1.0)));
+    int width = (int) ((0.0 + s.width() - left - min.width())*(rand()/(RAND_MAX + 1.0))) + min.width();
+    int height = (int) ((0.0 + s.height() - top - min.height())*(rand()/(RAND_MAX + 1.0))) + min.height();
+
+    return QRect(left, top, width, height);
+}
+
+void MainWindow::addShape()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    Shape::Type type;
+
+    if (sender() == actionAddCircle)
+        type = Shape::Circle;
+    else if (sender() == actionAddRectangle)
+        type = Shape::Rectangle;
+    else if (sender() == actionAddTriangle)
+        type = Shape::Triangle;
+    else return;
+
+    Shape newShape(type, randomColor(), randomRect(doc->size()));
+    doc->undoStack()->push(new AddShapeCommand(doc, newShape));
+}
+
+void MainWindow::removeShape()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    QString shapeName = doc->currentShapeName();
+    if (shapeName.isEmpty())
+        return;
+
+    doc->undoStack()->push(new RemoveShapeCommand(doc, shapeName));
+}
+
+void MainWindow::setShapeColor()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    QString shapeName = doc->currentShapeName();
+    if (shapeName.isEmpty())
+        return;
+
+    QColor color;
+
+    if (sender() == actionRed)
+        color = Qt::red;
+    else if (sender() == actionGreen)
+        color = Qt::green;
+    else if (sender() == actionBlue)
+        color = Qt::blue;
+    else
+        return;
+
+    if (color == doc->shape(shapeName).color())
+        return;
+
+    doc->undoStack()->push(new SetShapeColorCommand(doc, shapeName, color));
+}
+
+void MainWindow::addSnowman()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    // Create a macro command using beginMacro() and endMacro()
+
+    doc->undoStack()->beginMacro(tr("Add snowman"));
+    doc->undoStack()->push(new AddShapeCommand(doc,
+                            Shape(Shape::Circle, Qt::blue, QRect(51, 30, 97, 95))));
+    doc->undoStack()->push(new AddShapeCommand(doc,
+                            Shape(Shape::Circle, Qt::blue, QRect(27, 123, 150, 133))));
+    doc->undoStack()->push(new AddShapeCommand(doc,
+                            Shape(Shape::Circle, Qt::blue, QRect(11, 253, 188, 146))));
+    doc->undoStack()->endMacro();
+}
+
+void MainWindow::addRobot()
+{
+    Document *doc = currentDocument();
+    if (doc == 0)
+        return;
+
+    // Compose a macro command by explicitly adding children to a parent command
+
+    QUndoCommand *parent = new QUndoCommand(tr("Add robot"));
+
+    new AddShapeCommand(doc, Shape(Shape::Rectangle, Qt::green, QRect(115, 15, 81, 70)), parent);
+    new AddShapeCommand(doc, Shape(Shape::Rectangle, Qt::green, QRect(82, 89, 148, 188)), parent);
+    new AddShapeCommand(doc, Shape(Shape::Rectangle, Qt::green, QRect(76, 280, 80, 165)), parent);
+    new AddShapeCommand(doc, Shape(Shape::Rectangle, Qt::green, QRect(163, 280, 80, 164)), parent);
+    new AddShapeCommand(doc, Shape(Shape::Circle, Qt::blue, QRect(116, 25, 80, 50)), parent);
+    new AddShapeCommand(doc, Shape(Shape::Rectangle, Qt::green, QRect(232, 92, 80, 127)), parent);
+    new AddShapeCommand(doc, Shape(Shape::Rectangle, Qt::green, QRect(2, 92, 80, 125)), parent);
+
+    doc->undoStack()->push(parent);
+}
+
+void MainWindow::about()
+{
+    QMessageBox::about(this, tr("About Undo"), tr("The Undo demonstration shows how to use the Qt Undo framework."));
+}
+
+void MainWindow::aboutQt()
+{
+    QMessageBox::aboutQt(this, tr("About Qt"));
+}
diff --git a/demos/undo/mainwindow.h b/demos/undo/mainwindow.h
new file mode 100644
index 0000000000..4b74a5e7ae
--- /dev/null
+++ b/demos/undo/mainwindow.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef MAINWINDOW_H
+#define MAINWINDOW_H
+
+#include <QMainWindow>
+#include "ui_mainwindow.h"
+
+class Document;
+
+class MainWindow : public QMainWindow, public Ui::MainWindow
+{
+    Q_OBJECT
+
+public:
+    MainWindow(QWidget *parent = 0);
+
+    void addDocument(Document *doc);
+    void removeDocument(Document *doc);
+    void setCurrentDocument(Document *doc);
+    Document *currentDocument() const;
+
+public slots:
+    void openDocument();
+    void saveDocument();
+    void closeDocument();
+    void newDocument();
+
+    void addShape();
+    void removeShape();
+    void setShapeColor();
+
+    void addSnowman();
+    void addRobot();
+
+    void about();
+    void aboutQt();
+
+private slots:
+    void updateActions();
+
+private:
+    QUndoGroup *m_undoGroup;
+
+    QString fixedWindowTitle(const Document *doc) const;
+};
+
+#endif // MAINWINDOW_H
diff --git a/demos/undo/mainwindow.ui b/demos/undo/mainwindow.ui
new file mode 100644
index 0000000000..91a0b437e5
--- /dev/null
+++ b/demos/undo/mainwindow.ui
@@ -0,0 +1,322 @@
+<ui version="4.0" >
+ <class>MainWindow</class>
+ <widget class="QMainWindow" name="MainWindow" >
+  <property name="geometry" >
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>567</width>
+    <height>600</height>
+   </rect>
+  </property>
+  <property name="iconSize" >
+   <size>
+    <width>32</width>
+    <height>32</height>
+   </size>
+  </property>
+  <widget class="QWidget" name="centralwidget" >
+   <layout class="QVBoxLayout" >
+    <property name="margin" >
+     <number>0</number>
+    </property>
+    <property name="spacing" >
+     <number>0</number>
+    </property>
+    <item>
+     <widget class="QTabWidget" name="documentTabs" >
+      <property name="currentIndex" >
+       <number>0</number>
+      </property>
+      <widget class="QWidget" name="tab" >
+       <attribute name="title" >
+        <string>Tab 1</string>
+       </attribute>
+      </widget>
+     </widget>
+    </item>
+   </layout>
+  </widget>
+  <widget class="QMenuBar" name="menubar" >
+   <property name="geometry" >
+    <rect>
+     <x>0</x>
+     <y>0</y>
+     <width>567</width>
+     <height>27</height>
+    </rect>
+   </property>
+   <widget class="QMenu" name="menuFile" >
+    <property name="title" >
+     <string>File</string>
+    </property>
+    <addaction name="actionNew" />
+    <addaction name="actionOpen" />
+    <addaction name="actionSave" />
+    <addaction name="actionClose" />
+    <addaction name="separator" />
+    <addaction name="actionExit" />
+   </widget>
+   <widget class="QMenu" name="menuShape" >
+    <property name="title" >
+     <string>Edit</string>
+    </property>
+    <widget class="QMenu" name="menuMacros" >
+     <property name="title" >
+      <string>Macros</string>
+     </property>
+     <addaction name="actionAddRobot" />
+     <addaction name="actionAddSnowman" />
+    </widget>
+    <addaction name="separator" />
+    <addaction name="actionAddCircle" />
+    <addaction name="actionAddRectangle" />
+    <addaction name="actionAddTriangle" />
+    <addaction name="actionRemoveShape" />
+    <addaction name="separator" />
+    <addaction name="actionRed" />
+    <addaction name="actionGreen" />
+    <addaction name="actionBlue" />
+    <addaction name="separator" />
+    <addaction name="menuMacros" />
+   </widget>
+   <widget class="QMenu" name="menuHelp" >
+    <property name="title" >
+     <string>Help</string>
+    </property>
+    <addaction name="actionAbout" />
+    <addaction name="actionAboutQt" />
+   </widget>
+   <addaction name="menuFile" />
+   <addaction name="menuShape" />
+   <addaction name="menuHelp" />
+  </widget>
+  <widget class="QStatusBar" name="statusbar" />
+  <widget class="QToolBar" name="toolBar" >
+   <property name="windowTitle" >
+    <string>File actions</string>
+   </property>
+   <property name="orientation" >
+    <enum>Qt::Horizontal</enum>
+   </property>
+   <attribute name="toolBarArea" >
+    <enum>TopToolBarArea</enum>
+   </attribute>
+   <attribute name="toolBarBreak" >
+    <bool>false</bool>
+   </attribute>
+   <addaction name="actionNew" />
+   <addaction name="actionOpen" />
+   <addaction name="actionSave" />
+   <addaction name="actionClose" />
+   <addaction name="separator" />
+  </widget>
+  <widget class="QToolBar" name="shapeToolBar" >
+   <property name="windowTitle" >
+    <string>Shape actions</string>
+   </property>
+   <property name="orientation" >
+    <enum>Qt::Vertical</enum>
+   </property>
+   <attribute name="toolBarArea" >
+    <enum>LeftToolBarArea</enum>
+   </attribute>
+   <attribute name="toolBarBreak" >
+    <bool>false</bool>
+   </attribute>
+   <addaction name="actionAddRectangle" />
+   <addaction name="actionAddCircle" />
+   <addaction name="actionAddTriangle" />
+   <addaction name="actionRemoveShape" />
+   <addaction name="separator" />
+   <addaction name="actionRed" />
+   <addaction name="actionGreen" />
+   <addaction name="actionBlue" />
+  </widget>
+  <widget class="QDockWidget" name="dockWidget" >
+   <property name="windowTitle" >
+    <string>Undo Stack</string>
+   </property>
+   <attribute name="dockWidgetArea" >
+    <number>2</number>
+   </attribute>
+   <widget class="QWidget" name="dockWidgetContents" >
+    <layout class="QVBoxLayout" >
+     <property name="margin" >
+      <number>0</number>
+     </property>
+     <property name="spacing" >
+      <number>4</number>
+     </property>
+     <item>
+      <layout class="QHBoxLayout" >
+       <property name="margin" >
+        <number>0</number>
+       </property>
+       <property name="spacing" >
+        <number>6</number>
+       </property>
+       <item>
+        <spacer>
+         <property name="orientation" >
+          <enum>Qt::Horizontal</enum>
+         </property>
+         <property name="sizeHint" >
+          <size>
+           <width>40</width>
+           <height>20</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+       <item>
+        <widget class="QLabel" name="label" >
+         <property name="text" >
+          <string>Undo limit</string>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <widget class="QSpinBox" name="undoLimit" />
+       </item>
+      </layout>
+     </item>
+     <item>
+      <widget class="QUndoView" name="undoView" >
+       <property name="alternatingRowColors" >
+        <bool>false</bool>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </widget>
+  </widget>
+  <action name="actionOpen" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/fileopen.png</iconset>
+   </property>
+   <property name="text" >
+    <string>&amp;Open</string>
+   </property>
+  </action>
+  <action name="actionClose" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/fileclose.png</iconset>
+   </property>
+   <property name="text" >
+    <string>&amp;Close</string>
+   </property>
+  </action>
+  <action name="actionNew" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/filenew.png</iconset>
+   </property>
+   <property name="text" >
+    <string>&amp;New</string>
+   </property>
+  </action>
+  <action name="actionSave" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/filesave.png</iconset>
+   </property>
+   <property name="text" >
+    <string>&amp;Save</string>
+   </property>
+  </action>
+  <action name="actionExit" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/exit.png</iconset>
+   </property>
+   <property name="text" >
+    <string>E&amp;xit</string>
+   </property>
+  </action>
+  <action name="actionRed" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/red.png</iconset>
+   </property>
+   <property name="text" >
+    <string>Red</string>
+   </property>
+  </action>
+  <action name="actionGreen" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/green.png</iconset>
+   </property>
+   <property name="text" >
+    <string>Green</string>
+   </property>
+  </action>
+  <action name="actionBlue" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/blue.png</iconset>
+   </property>
+   <property name="text" >
+    <string>Blue</string>
+   </property>
+  </action>
+  <action name="actionAddRectangle" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/rectangle.png</iconset>
+   </property>
+   <property name="text" >
+    <string>Add Rectangle</string>
+   </property>
+  </action>
+  <action name="actionAddCircle" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/circle.png</iconset>
+   </property>
+   <property name="text" >
+    <string>Add Circle</string>
+   </property>
+  </action>
+  <action name="actionRemoveShape" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/remove.png</iconset>
+   </property>
+   <property name="text" >
+    <string>Remove Shape</string>
+   </property>
+  </action>
+  <action name="actionAddRobot" >
+   <property name="text" >
+    <string>Add robot</string>
+   </property>
+  </action>
+  <action name="actionAddSnowman" >
+   <property name="text" >
+    <string>Add snowan</string>
+   </property>
+  </action>
+  <action name="actionAddTriangle" >
+   <property name="icon" >
+    <iconset resource="undo.qrc" >:/icons/triangle.png</iconset>
+   </property>
+   <property name="text" >
+    <string>addTriangle</string>
+   </property>
+  </action>
+  <action name="actionAbout" >
+   <property name="text" >
+    <string>About</string>
+   </property>
+  </action>
+  <action name="actionAboutQt" >
+   <property name="text" >
+    <string>About Qt</string>
+   </property>
+  </action>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>QUndoView</class>
+   <extends>QListView</extends>
+   <header>qundoview.h</header>
+  </customwidget>
+ </customwidgets>
+ <resources>
+  <include location="undo.qrc" />
+ </resources>
+ <connections/>
+</ui>
diff --git a/demos/undo/undo.pro b/demos/undo/undo.pro
new file mode 100644
index 0000000000..ba647cb95d
--- /dev/null
+++ b/demos/undo/undo.pro
@@ -0,0 +1,18 @@
+SOURCES += main.cpp mainwindow.cpp commands.cpp document.cpp
+HEADERS += mainwindow.h commands.h document.h
+FORMS += mainwindow.ui
+
+build_all:!build_pass {
+    CONFIG -= build_all
+    CONFIG += release
+}
+
+RESOURCES += undo.qrc
+
+# install
+target.path = $$[QT_INSTALL_DEMOS]/qtbase/undo
+sources.files = $$SOURCES $$HEADERS *.pro icons $$RESOURCES $$FORMS
+sources.path = $$[QT_INSTALL_DEMOS]/qtbase/undo
+INSTALLS += target sources
+
+symbian: include($$QT_SOURCE_TREE/demos/symbianpkgrules.pri)
diff --git a/demos/undo/undo.qrc b/demos/undo/undo.qrc
new file mode 100644
index 0000000000..65619b8f1a
--- /dev/null
+++ b/demos/undo/undo.qrc
@@ -0,0 +1,20 @@
+<RCC>
+    <qresource prefix="/" >
+        <file>icons/background.png</file>
+        <file>icons/blue.png</file>
+        <file>icons/circle.png</file>
+        <file>icons/exit.png</file>
+        <file>icons/fileclose.png</file>
+        <file>icons/filenew.png</file>
+        <file>icons/fileopen.png</file>
+        <file>icons/filesave.png</file>
+        <file>icons/green.png</file>
+        <file>icons/ok.png</file>
+        <file>icons/rectangle.png</file>
+        <file>icons/red.png</file>
+        <file>icons/redo.png</file>
+        <file>icons/remove.png</file>
+        <file>icons/triangle.png</file>
+        <file>icons/undo.png</file>
+    </qresource>
+</RCC>