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50
51#include "timemodel.h"
52
53int TimeModel::instances=0;
54MinuteTimer *TimeModel::timer=nullptr;
55
56void MinuteTimer::start()
57{
58 if (!timer.isActive()) {
59 time = QTime::currentTime();
60 timer.start(msec: 60000-time.second()*1000, obj: this);
61 }
62}
63
64void MinuteTimer::stop()
65{
66 timer.stop();
67}
68
69void MinuteTimer::timerEvent(QTimerEvent *)
70{
71 QTime now = QTime::currentTime();
72 if (now.second() == 59 && now.minute() == time.minute() && now.hour() == time.hour()) {
73 // just missed time tick over, force it, wait extra 0.5 seconds
74 time = time.addSecs(secs: 60);
75 timer.start(msec: 60500, obj: this);
76 } else {
77 time = now;
78 timer.start(msec: 60000-time.second()*1000, obj: this);
79 }
80 emit timeChanged();
81}
82
83TimeModel::TimeModel(QObject *parent) : QObject(parent)
84{
85 if (++instances == 1) {
86 if (!timer)
87 timer = new MinuteTimer(QCoreApplication::instance());
88 connect(sender: timer, signal: &MinuteTimer::timeChanged, receiver: this, slot: &TimeModel::timeChanged);
89 timer->start();
90 }
91}
92
93TimeModel::~TimeModel()
94{
95 if (--instances == 0) {
96 timer->stop();
97 }
98}
99

source code of qtdeclarative/examples/qml/qmlextensionplugins/timemodel.cpp