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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (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
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+** 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
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+**
+** 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
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+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
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+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+    \example draganddrop/draggableicons
+    \title Draggable Icons Example
+
+    The Draggable Icons example shows how to drag and drop image data between widgets
+    in the same application, and between different applications.
+
+    \image draggableicons-example.png
+
+    In many situations where drag and drop is used, the user starts dragging from
+    a particular widget and drops the payload onto another widget. In this example,
+    we subclass QLabel to create labels that we use as drag sources, and place them
+    inside \l{QWidget}s that serve as both containers and drop sites.
+
+    In addition, when a drag and drop operation occurs, we want to send more than
+    just an image. We also want to send information about where the user clicked in
+    the image so that the user can place it precisely on the drop target. This level
+    of detail means that we must create a custom MIME type for our data.
+
+    \section1 DragWidget Class Definition
+
+    The icon widgets that we use to display icons are subclassed from QLabel:
+
+    \snippet examples/draganddrop/draggableicons/dragwidget.h 0
+
+    Since the QLabel class provides most of what we require for the icon, we
+    only need to reimplement the \l QWidget::mousePressEvent() to provide
+    drag and drop facilities.
+
+    \section1 DragWidget Class Implementation
+
+    The \c DragWidget constructor sets an attribute on the widget that ensures
+    that it will be deleted when it is closed:
+
+    \snippet examples/draganddrop/draggableicons/dragwidget.cpp 0
+
+    To enable dragging from the icon, we need to act on a mouse press event.
+    We do this by reimplementing \l QWidget::mousePressEvent() and setting up
+    a QDrag object.
+
+    \snippet examples/draganddrop/draggableicons/dragwidget.cpp 1
+
+    Since we will be sending pixmap data for the icon and information about the
+    user's click in the icon widget, we construct a QByteArray and package up the
+    details using a QDataStream.
+
+    For interoperability, drag and drop operations describe the data they contain
+    using MIME types. In Qt, we describe this data using a QMimeData object:
+
+    \snippet examples/draganddrop/draggableicons/dragwidget.cpp 2
+
+    We choose an unofficial MIME type for this purpose, and supply the QByteArray
+    to the MIME data object.
+
+    The drag and drop operation itself is handled by a QDrag object:
+
+    \snippet examples/draganddrop/draggableicons/dragwidget.cpp 3
+
+    Here, we pass the data to the drag object, set a pixmap that will be shown
+    alongside the cursor during the operation, and define the position of a hot
+    spot that places the position of this pixmap under the cursor.
+
+*/