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/*!+
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    \example itemviews/spinboxdelegate+
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    \title Spin Box Delegate Example+
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+
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    The Spin Box Delegate example shows how to create an editor for a custom delegate in+
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    the model/view framework by reusing a standard Qt editor widget.+
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+
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    The model/view framework provides a standard delegate that is used by default+
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    with the standard view classes. For most purposes, the selection of editor+
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    widgets available through this delegate is sufficient for editing text, boolean+
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    values, and other simple data types. However, for specific data types, it is+
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    sometimes necessary to use a custom delegate to either display the data in a+
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    specific way, or allow the user to edit it with a custom control.+
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+
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    \image spinboxdelegate-example.png+
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+
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    This concepts behind this example are covered in the+
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    \l{model-view-delegate.html}{Delegate Classes} chapter of the+
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    \l{model-view-programming.html}{Model/View Programming} overview.+
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+
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    \section1 SpinBoxDelegate Class Definition+
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+
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    The definition of the delegate is as follows:+
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+
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    \snippet examples/itemviews/spinboxdelegate/delegate.h 0+
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+
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    The delegate class declares only those functions that are needed to+
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    create an editor widget, display it at the correct location in a view,+
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    and communicate with a model. Custom delegates can also provide their+
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    own painting code by reimplementing the \c paintEvent() function.+
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+
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    \section1 SpinBoxDelegate Class Implementation+
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+
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    Since the delegate is stateless, the constructor only needs to+
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    call the base class's constructor with the parent QObject as its+
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    argument:+
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+
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    \snippet examples/itemviews/spinboxdelegate/delegate.cpp 0+
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+
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    Since the delegate is a subclass of QItemDelegate, the data it retrieves+
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    from the model is displayed in a default style, and we do not need to+
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    provide a custom \c paintEvent().+
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+
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    The \c createEditor() function returns an editor widget, in this case a+
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    spin box that restricts values from the model to integers from 0 to 100+
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    inclusive.+
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+
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    \snippet examples/itemviews/spinboxdelegate/delegate.cpp 1+
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+
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    We install an event filter on the spin box to ensure that it behaves in+
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    a way that is consistent with other delegates. The implementation for+
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    the event filter is provided by the base class.+
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+
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    The \c setEditorData() function reads data from the model, converts it+
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    to an integer value, and writes it to the editor widget.+
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+
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    \snippet examples/itemviews/spinboxdelegate/delegate.cpp 2+
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+
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    Since the view treats delegates as ordinary QWidget instances, we have+
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    to use a static cast before we can set the value in the spin box.+
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+
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    The \c setModelData() function reads the contents of the spin box, and+
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    writes it to the model.+
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+
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    \snippet examples/itemviews/spinboxdelegate/delegate.cpp 3+
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+
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    We call \l{QSpinBox::interpretText()}{interpretText()} to make sure that+
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    we obtain the most up-to-date value in the spin box.+
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+
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    The \c updateEditorGeometry() function updates the editor widget's+
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    geometry using the information supplied in the style option. This is the+
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    minimum that the delegate must do in this case.+
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+
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    \snippet examples/itemviews/spinboxdelegate/delegate.cpp 4+
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+
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    More complex editor widgets may divide the rectangle available in+
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    \c{option.rect} between different child widgets if required.+
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+
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    \section1 The Main Function+
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+
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    This example is written in a slightly different way to many of the+
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    other examples supplied with Qt. To demonstrate the use of a custom+
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    editor widget in a standard view, it is necessary to set up a model+
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    containing some arbitrary data and a view to display it.+
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+
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    We set up the application in the normal way, construct a standard item+
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    model to hold some data, set up a table view to use the data in the+
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    model, and construct a custom delegate to use for editing:+
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+
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    \snippet examples/itemviews/spinboxdelegate/main.cpp 0+
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+
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    The table view is informed about the delegate, and will use it to+
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    display each of the items. Since the delegate is a subclass of+
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    QItemDelegate, each cell in the table will be rendered using standard+
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    painting operations.+
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+
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    We insert some arbitrary data into the model for demonstration purposes:+
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+
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    \snippet examples/itemviews/spinboxdelegate/main.cpp 1+
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    \snippet examples/itemviews/spinboxdelegate/main.cpp 2+
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+
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    Finally, the table view is displayed with a window title, and we start+
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    the application's event loop:+
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+
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    \snippet examples/itemviews/spinboxdelegate/main.cpp 3+
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+
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    Each of the cells in the table can now be edited in the usual way, but+
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    the spin box ensures that the data returned to the model is always+
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    constrained by the values allowed by the spin box delegate.+
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*/+
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