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50
51#include "starrating.h"
52
53#include <QtWidgets>
54#include <cmath>
55
56constexpr int PaintingScaleFactor = 20;
57
58//! [0]
59StarRating::StarRating(int starCount, int maxStarCount)
60 : myStarCount(starCount),
61 myMaxStarCount(maxStarCount)
62{
63 starPolygon << QPointF(1.0, 0.5);
64 for (int i = 1; i < 5; ++i)
65 starPolygon << QPointF(0.5 + 0.5 * std::cos(0.8 * i * 3.14),
66 0.5 + 0.5 * std::sin(0.8 * i * 3.14));
67
68 diamondPolygon << QPointF(0.4, 0.5) << QPointF(0.5, 0.4)
69 << QPointF(0.6, 0.5) << QPointF(0.5, 0.6)
70 << QPointF(0.4, 0.5);
71}
72//! [0]
73
74//! [1]
75QSize StarRating::sizeHint() const
76{
77 return PaintingScaleFactor * QSize(myMaxStarCount, 1);
78}
79//! [1]
80
81//! [2]
82void StarRating::paint(QPainter *painter, const QRect &rect,
83 const QPalette &palette, EditMode mode) const
84{
85 painter->save();
86
87 painter->setRenderHint(QPainter::Antialiasing, true);
88 painter->setPen(Qt::NoPen);
89 painter->setBrush(mode == EditMode::Editable ?
90 palette.highlight() :
91 palette.windowText());
92
93 const int yOffset = (rect.height() - PaintingScaleFactor) / 2;
94 painter->translate(rect.x(), rect.y() + yOffset);
95 painter->scale(PaintingScaleFactor, PaintingScaleFactor);
96
97 for (int i = 0; i < myMaxStarCount; ++i) {
98 if (i < myStarCount)
99 painter->drawPolygon(starPolygon, Qt::WindingFill);
100 else if (mode == EditMode::Editable)
101 painter->drawPolygon(diamondPolygon, Qt::WindingFill);
102 painter->translate(1.0, 0.0);
103 }
104
105 painter->restore();
106}
107//! [2]
108