- Qt 5.5
- Qt Widgets
- Star Delegate Example
- stardelegate.cpp Example File
- Qt 5.5.1 Reference Documentation

# stardelegate.cpp Example File

itemviews/stardelegate/stardelegate.cpp

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
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    ** modification, are permitted provided that the following conditions are
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    **     from this software without specific prior written permission.
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    #include <QtWidgets>

    #include "stardelegate.h"
    #include "stareditor.h"
    #include "starrating.h"

    void StarDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                             const QModelIndex &index) const
    {
        if (index.data().canConvert<StarRating>()) {
            StarRating starRating = qvariant_cast<StarRating>(index.data());

            if (option.state & QStyle::State_Selected)
                painter->fillRect(option.rect, option.palette.highlight());

            starRating.paint(painter, option.rect, option.palette,
                             StarRating::ReadOnly);
        } else {
            QStyledItemDelegate::paint(painter, option, index);
        }
    }

    QSize StarDelegate::sizeHint(const QStyleOptionViewItem &option,
                                 const QModelIndex &index) const
    {
        if (index.data().canConvert<StarRating>()) {
            StarRating starRating = qvariant_cast<StarRating>(index.data());
            return starRating.sizeHint();
        } else {
            return QStyledItemDelegate::sizeHint(option, index);
        }
    }

    QWidget *StarDelegate::createEditor(QWidget *parent,
                                        const QStyleOptionViewItem &option,
                                        const QModelIndex &index) const

    {
        if (index.data().canConvert<StarRating>()) {
            StarEditor *editor = new StarEditor(parent);
            connect(editor, SIGNAL(editingFinished()),
                    this, SLOT(commitAndCloseEditor()));
            return editor;
        } else {
            return QStyledItemDelegate::createEditor(parent, option, index);
        }
    }

    void StarDelegate::setEditorData(QWidget *editor,
                                     const QModelIndex &index) const
    {
        if (index.data().canConvert<StarRating>()) {
            StarRating starRating = qvariant_cast<StarRating>(index.data());
            StarEditor *starEditor = qobject_cast<StarEditor *>(editor);
            starEditor->setStarRating(starRating);
        } else {
            QStyledItemDelegate::setEditorData(editor, index);
        }
    }

    void StarDelegate::setModelData(QWidget *editor, QAbstractItemModel *model,
                                    const QModelIndex &index) const
    {
        if (index.data().canConvert<StarRating>()) {
            StarEditor *starEditor = qobject_cast<StarEditor *>(editor);
            model->setData(index, QVariant::fromValue(starEditor->starRating()));
        } else {
            QStyledItemDelegate::setModelData(editor, model, index);
        }
    }

    void StarDelegate::commitAndCloseEditor()
    {
        StarEditor *editor = qobject_cast<StarEditor *>(sender());
        emit commitData(editor);
        emit closeEditor(editor);
    }