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50
51#include "pixeldelegate.h"
52
53#include <QPainter>
54
55//! [0]
56PixelDelegate::PixelDelegate(QObject *parent)
57 : QAbstractItemDelegate(parent), pixelSize(12)
58{}
59//! [0]
60
61//! [1]
62void PixelDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
63 const QModelIndex &index) const
64{
65//! [2]
66 if (option.state & QStyle::State_Selected)
67 painter->fillRect(option.rect, option.palette.highlight());
68//! [1]
69
70//! [3]
71 const int size = qMin(a: option.rect.width(), b: option.rect.height());
72//! [3] //! [4]
73 const int brightness = index.model()->data(index, role: Qt::DisplayRole).toInt();
74 const double radius = (size / 2.0) - (brightness / 255.0 * size / 2.0);
75 if (qFuzzyIsNull(d: radius))
76 return;
77//! [4]
78
79//! [5]
80 painter->save();
81//! [5] //! [6]
82 painter->setRenderHint(hint: QPainter::Antialiasing, on: true);
83//! [6] //! [7]
84 painter->setPen(Qt::NoPen);
85//! [7] //! [8]
86 if (option.state & QStyle::State_Selected)
87//! [8] //! [9]
88 painter->setBrush(option.palette.highlightedText());
89 else
90//! [2]
91 painter->setBrush(option.palette.text());
92//! [9]
93
94//! [10]
95 painter->drawEllipse(r: QRectF(option.rect.x() + option.rect.width() / 2 - radius,
96 option.rect.y() + option.rect.height() / 2 - radius,
97 2 * radius, 2 * radius));
98 painter->restore();
99}
100//! [10]
101
102//! [11]
103QSize PixelDelegate::sizeHint(const QStyleOptionViewItem & /* option */,
104 const QModelIndex & /* index */) const
105{
106 return QSize(pixelSize, pixelSize);
107}
108//! [11]
109
110//! [12]
111void PixelDelegate::setPixelSize(int size)
112{
113 pixelSize = size;
114}
115//! [12]
116

source code of qtbase/examples/widgets/itemviews/pixelator/pixeldelegate.cpp