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50
51#include "worldtimeclock.h"
52
53#include <QMouseEvent>
54#include <QPainter>
55#include <QTimer>
56
57WorldTimeClock::WorldTimeClock(QWidget *parent)
58 : QWidget(parent)
59{
60 QTimer *timer = new QTimer(this);
61 connect(sender: timer, signal: &QTimer::timeout, receiver: this, slot: QOverload<>::of(ptr: &QWidget::update));
62 timer->start(msec: 1000);
63
64 setWindowTitle(tr(s: "World Time Clock"));
65 resize(w: 200, h: 200);
66}
67
68void WorldTimeClock::paintEvent(QPaintEvent *)
69{
70 static const QPoint hourHand[3] = {
71 QPoint(7, 8),
72 QPoint(-7, 8),
73 QPoint(0, -40)
74 };
75 static const QPoint minuteHand[3] = {
76 QPoint(7, 8),
77 QPoint(-7, 8),
78 QPoint(0, -70)
79 };
80
81 QColor hourColor(127, 0, 127);
82 QColor minuteColor(0, 127, 127, 191);
83
84 int side = qMin(a: width(), b: height());
85 QTime time = QTime::currentTime();
86 time = time.addSecs(secs: timeZoneOffset);
87
88 QPainter painter(this);
89 painter.setRenderHint(hint: QPainter::Antialiasing);
90 painter.translate(dx: width() / 2, dy: height() / 2);
91 painter.scale(sx: side / 200.0, sy: side / 200.0);
92
93 painter.setPen(Qt::NoPen);
94 painter.setBrush(hourColor);
95
96 painter.save();
97 painter.rotate(a: 30.0 * ((time.hour() + time.minute() / 60.0)));
98 painter.drawConvexPolygon(points: hourHand, pointCount: 3);
99 painter.restore();
100
101 painter.setPen(hourColor);
102
103 for (int i = 0; i < 12; ++i) {
104 painter.drawLine(x1: 88, y1: 0, x2: 96, y2: 0);
105 painter.rotate(a: 30.0);
106 }
107
108 painter.setPen(Qt::NoPen);
109 painter.setBrush(minuteColor);
110
111 painter.save();
112 painter.rotate(a: 6.0 * (time.minute() + time.second() / 60.0));
113 painter.drawConvexPolygon(points: minuteHand, pointCount: 3);
114 painter.restore();
115
116 painter.setPen(minuteColor);
117
118 for (int j = 0; j < 60; ++j) {
119 if ((j % 5) != 0)
120 painter.drawLine(x1: 92, y1: 0, x2: 96, y2: 0);
121 painter.rotate(a: 6.0);
122 }
123
124 emit updated(currentTime: time);
125}
126
127void WorldTimeClock::setTimeZone(int hourOffset)
128{
129 timeZoneOffset = qMin(a: qMax(a: -12, b: hourOffset), b: 12) * 3600;
130 update();
131}
132

source code of qttools/examples/designer/worldtimeclockplugin/worldtimeclock.cpp