source: trunk/src/gui/itemviews/qabstractitemdelegate.cpp@ 746

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#include "qabstractitemdelegate.h"

#ifndef QT_NO_ITEMVIEWS
#include <qabstractitemmodel.h>
#include <qabstractitemview.h>
#include <qfontmetrics.h>
#include <qwhatsthis.h>
#include <qtooltip.h>
#include <qevent.h>
#include <qstring.h>
#include <qdebug.h>
#include <private/qtextengine_p.h>

QT_BEGIN_NAMESPACE

/*!
    \class QAbstractItemDelegate

    \brief The QAbstractItemDelegate class is used to display and edit
    data items from a model.

    \ingroup model-view


    A QAbstractItemDelegate provides the interface and common functionality
    for delegates in the model/view architecture. Delegates display
    individual items in views, and handle the editing of model data.

    The QAbstractItemDelegate class is one of the \l{Model/View Classes}
    and is part of Qt's \l{Model/View Programming}{model/view framework}.

    To render an item in a custom way, you must implement paint() and
    sizeHint(). The QItemDelegate class provides default implementations for
    these functions; if you do not need custom rendering, subclass that
    class instead.

    We give an example of drawing a progress bar in items; in our case
    for a package management program.

    \image widgetdelegate.png

    We create the \c WidgetDelegate class, which inherits from
    QStyledItemDelegate. We do the drawing in the paint() function:

    \snippet doc/src/snippets/widgetdelegate.cpp 0

    Notice that we use a QStyleOptionProgressBar and initialize its
    members. We can then use the current QStyle to draw it.

    To provide custom editing, there are two approaches that can be
    used. The first approach is to create an editor widget and display
    it directly on top of the item. To do this you must reimplement
    createEditor() to provide an editor widget, setEditorData() to populate
    the editor with the data from the model, and setModelData() so that the
    delegate can update the model with data from the editor.

    The second approach is to handle user events directly by reimplementing
    editorEvent().

    \sa {model-view-programming}{Model/View Programming}, QItemDelegate,
        {Pixelator Example}, QStyledItemDelegate, QStyle
*/

/*!
    \enum QAbstractItemDelegate::EndEditHint

    This enum describes the different hints that the delegate can give to the
    model and view components to make editing data in a model a comfortable
    experience for the user.

    \value NoHint           There is no recommended action to be performed.