source: trunk/doc/src/examples/sipdialog.qdoc@ 651

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/*!
    \example dialogs/sipdialog
    \title SIP Dialog Example
    \ingroup qtce

    The SIP Dialog example shows how to create a dialog that is aware of 
    the Windows Mobile SIP (Software Input Panel) and reacts to it.

    \table
    \row \o \inlineimage sipdialog-closed.png
         \o \inlineimage sipdialog-opened.png
    \endtable

    Sometimes it is necessary for a dialog to take the SIP into account,
    as the SIP may hide important input widgets. The SIP Dialog Example
    shows how a \c Dialog object, \c dialog, can be resized accordingly
    if the SIP is opened, by embedding the contents of \c dialog in a
    QScrollArea.

    \section1 Dialog Class Definition

    The \c Dialog class is a subclass of QDialog that implements a public
    slot, \c desktopResized(), and a public function, \c reactToSIP(). Also,
    it holds a private instance of QRect, \c desktopGeometry.

    \snippet dialogs/sipdialog/dialog.h Dialog header

    \section1 Dialog Class Implementation

    In the constructor of \c Dialog, we start by obtaining the
    available geometry of the screen with
    \l{QDesktopWidget::availableGeometry()}{availableGeometry()}. The
    parameter used is \c 0 to indicate that we require the primary screen.

    \snippet dialogs/sipdialog/dialog.cpp Dialog constructor part1

    We set the window's title to "SIP Dialog Example" and declare a QScrollArea
    object, \c scrollArea. Next we instantiate a QGroupBox, \c groupBox, with
    \c scrollArea as its parent. The title of \c groupBox is also set to
    "SIP Dialog Example". A QGridLayout object, \c gridLayout, is then used
    as \c{groupBox}'s layout.

    We create a QLineEdit, a QLabel and a QPushButton and we set the
    \l{QWidget::setMinimumWidth()}{minimumWidth} property to 220 pixels,
    respectively.

    \snippet dialogs/sipdialog/dialog.cpp Dialog constructor part2

    Also, all three widgets' text are set accordingly. The
    \l{QGridLayout::setVerticalSpacing()}{verticalSpacing} property of
    \c gridLayout is set based on the height of \c desktopGeometry. This
    is to adapt to the different form factors of Windows Mobile. Then, we
    add our widgets to the layout.

    \snippet dialogs/sipdialog/dialog.cpp Dialog constructor part3

    The \c{scrollArea}'s widget is set to \c groupBox. We use a QHBoxLayout
    object, \c layout, to contain \c scrollArea. The \c{Dialog}'s layout
    is set to \c layout and the scroll area's horizontal scroll bar is turned
    off.

    \snippet dialogs/sipdialog/dialog.cpp Dialog constructor part4

    The following signals are connected to their respective slots:
    \list
        \o \c{button}'s \l{QPushButton::pressed()}{pressed()} signal to
        \l{QApplication}'s \l{QApplication::closeAllWindows()}
        {closeAllWindows()} slot,
        \o \l{QDesktopWidget}'s \l{QDesktopWidget::workAreaResized()}
        {workAreaResized()} signal to \c{dialog}'s \c desktopResized() slot.
    \endlist

    \snippet dialogs/sipdialog/dialog.cpp Dialog constructor part5

    The \c desktopResized() function accepts an integer, \a screen,
    corresponding to the screen's index. We only invoke \c reactToSIP()
    if \a screen is the primary screen (e.g. index = 0).

    \snippet dialogs/sipdialog/dialog.cpp desktopResized() function

    The \c reactToSIP() function resizes \c dialog accordingly if the
    desktop's available geometry changed vertically, as this change signifies
    that the SIP may have been opened or closed.

    \snippet dialogs/sipdialog/dialog.cpp reactToSIP() function

    If the height has decreased, we unset the maximized window state.
    Otherwise, we set the maximized window state. Lastly, we update
    \c desktopGeometry to the desktop's available geometry.

    \section1 The \c main() function

    The \c main() function for the SIP Dialog example instantiates \c Dialog
    and invokes its \l{QDialog::exec()}{exec()} function.

    \snippet dialogs/sipdialog/main.cpp main() function

    \note Although this example uses a dialog, the techniques used here apply to
    all top-level widgets respectively.
*/