- Qt 5.5
- Qt Widgets
- Pixelator Example
- pixeldelegate.cpp Example File
- Qt 5.5.1 Reference Documentation

# pixeldelegate.cpp Example File

itemviews/pixelator/pixeldelegate.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.
    **
    ** $QT_BEGIN_LICENSE:BSD$
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    #include "pixeldelegate.h"

    #include <QPainter>

    PixelDelegate::PixelDelegate(QObject *parent)
        : QAbstractItemDelegate(parent)
    {
        pixelSize = 12;
    }

    void PixelDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                              const QModelIndex &index) const
    {
        if (option.state & QStyle::State_Selected)
            painter->fillRect(option.rect, option.palette.highlight());

        int size = qMin(option.rect.width(), option.rect.height());
        int brightness = index.model()->data(index, Qt::DisplayRole).toInt();
        double radius = (size / 2.0) - (brightness / 255.0 * size / 2.0);
        if (radius == 0.0)
            return;

        painter->save();
        painter->setRenderHint(QPainter::Antialiasing, true);
        painter->setPen(Qt::NoPen);
        if (option.state & QStyle::State_Selected)
            painter->setBrush(option.palette.highlightedText());
        else
            painter->setBrush(option.palette.text());

        painter->drawEllipse(QRectF(option.rect.x() + option.rect.width() / 2 - radius,
                                    option.rect.y() + option.rect.height() / 2 - radius,
                                    2 * radius, 2 * radius));
        painter->restore();
    }

    QSize PixelDelegate::sizeHint(const QStyleOptionViewItem & /* option */,
                                  const QModelIndex & /* index */) const
    {
        return QSize(pixelSize, pixelSize);
    }

    void PixelDelegate::setPixelSize(int size)
    {
        pixelSize = size;
    }