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+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial Usage
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in a
+** written agreement between you and Nokia.
+**
+** GNU Free Documentation License
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of this
+** file.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*! \example widgets/orientation
+    \group all-examples
+    \title Orientation Example
+
+    The example shows a simple way to use different UIs depending on the screen
+    orientation of a mobile device.
+
+    \image orientation-landscape.png The UI in landscape mode
+    \image orientation-portrait.png The UI in portrait mode
+
+    The screen on many mobile devices can be viewed in both portrait and
+    landscape orientation. The orientation can be swiched with the help of a
+    hardware or software trigger. Due to the often small physical screen size,
+    user interfaces has to be very simple and compact to stay usable, and
+    applications usually occupy the whole screen. Designing a user interface
+    that works equally well in both landscape and portrait mode is not always
+    possible, however, so making a different layout for each case usually pays
+    off.
+
+    The example application makes use of two different UI widgets created with
+    the Qt Designer, one for portrait and one for landscape orientation. The
+    application has a widget that contains an image and the user is able to
+    select one of three images for it to show. In addition to the two UIs, the
+    application consists of a \c MainWindow class.
+
+    \section1 Landscape UI
+
+    If the screen is in landscape mode, the user probably holds the device with
+    both hands and is ready to give full attention to the application. The
+    landscape UI looks like this:
+
+    \image orientation-landscape-ui.png The landscape UI
+
+    To the left is a QWidget called \c choiceWidget, which will show the
+    current image, and to the right are three QRadioButton instances. The
+    active radio button specifies the image to show.
+
+    \section1 Portrait UI
+
+    When the device is in portrait mode, it usually means that the user holds
+    it with one hand, and can comfortably use the thumb for small amounts of
+    input. The layout is simpler, and is focused on consuming content. The
+    portrait UI looks like this:
+
+    \image orientation-portrait-ui.png The portrait UI
+
+    Similarly, it contains a QWidget, also called \c choiceWidget, that will
+    show the current image. In contrast to the landscape UI, this one doesn't
+    provide any controls to change the image.
+
+    \section1 MainWindow Class Definition
+
+    \c MainWindow inherits from QWidget and acts as the top level widget of the
+    application.
+
+    \snippet examples/widgets/orientation/mainwindow.h 0
+
+    The \c resizeEvent() method is re-implemented, and used to check which
+    UI to show. The \c onRadioButtonClicked() slot is connected to the
+    landscape UI's radio button group and selects the current image.
+
+    \c landscapeWidget and \c portraitWidget will contain the UI layouts. Only
+    one of them is visible at a time.
+
+    \section1 MainWindow Class Implementation
+
+    In the constructor, the widgets that will hold the UIs are created and set
+    up.
+
+    \snippet examples/widgets/orientation/mainwindow.cpp 0
+
+    Since the exit buttons on the layouts are different from each other, both
+    of them have to have their \c clicked() signal connected to the \c close()
+    slot of the main widget. The first image is also made current with the call
+    to \c onRadioButtonClicked().
+
+    \snippet examples/widgets/orientation/mainwindow.cpp 1
+
+    On the Maemo platform, windows are stuck in landscape mode by default. The
+    application has to explicitly say that rotation is supported.
+
+    \snippet examples/widgets/orientation/mainwindow.cpp 2
+
+    The \c resizeEvent() is called when the main window is first created, and
+    also whenever the window has been resized. If the window is shown in
+    full screen, this is an indication that the orientation of the screen has
+    changed.
+
+    The dimensions of \c landscapeWidget is the transpose of the dimensions of
+    \c portraitWidget. When the orientation is known, both are set to the
+    (possibly transposed) size of the window. Depending on the orientation, one
+    widget is made visible and the other invisible.
+
+    \snippet examples/widgets/orientation/mainwindow.cpp 3
+
+    When the user selects one of the radio buttons in the landscape UI, the
+    current image is changed. The image is displayed by specifying the
+    background style of the choice widget. Since both \c portrait and
+    \c landscape have a \c choiceWidget of their own, the change has to be
+    reflected in both instances.
+
+    \snippet examples/widgets/orientation/mainwindow.cpp 4
+
+    Synchronizing both UIs like this might become unfeasible when there are
+    many things that can change. In that case it is better to make use of the
+    \l{Introduction to Model/View Programming}{Model-View-Controller pattern}
+    more extensively and share the content between both portrait and landscape
+    widgets. Then an interface for displaying and manipulating it can be tailor
+    made for both orientations.
+
+    \section1 The \c main() Function
+
+    The main function creates a \c MainWindow instance and shows it full
+    screen.
+    \snippet examples/widgets/orientation/main.cpp 0
+*/