1/****************************************************************************
2**
3** Copyright (C) 2017 The Qt Company Ltd.
4** Contact: https://www.qt.io/licensing/
5**
6** This file is part of the examples of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:BSD$
9** Commercial License Usage
10** Licensees holding valid commercial Qt licenses may use this file in
11** accordance with the commercial license agreement provided with the
12** Software or, alternatively, in accordance with the terms contained in
13** a written agreement between you and The Qt Company. For licensing terms
14** and conditions see https://www.qt.io/terms-conditions. For further
15** information use the contact form at https://www.qt.io/contact-us.
16**
17** BSD License Usage
18** Alternatively, you may use this file under the terms of the BSD license
19** as follows:
20**
21** "Redistribution and use in source and binary forms, with or without
22** modification, are permitted provided that the following conditions are
23** met:
24** * Redistributions of source code must retain the above copyright
25** notice, this list of conditions and the following disclaimer.
26** * Redistributions in binary form must reproduce the above copyright
27** notice, this list of conditions and the following disclaimer in
28** the documentation and/or other materials provided with the
29** distribution.
30** * Neither the name of The Qt Company Ltd nor the names of its
31** contributors may be used to endorse or promote products derived
32** from this software without specific prior written permission.
33**
34**
35** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
36** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
37** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
38** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
39** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
42** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
43** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
44** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
45** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
46**
47** $QT_END_LICENSE$
48**
49****************************************************************************/
50#include <QtCore>
51
52#include "logfilepositionsource.h"
53
54LogFilePositionSource::LogFilePositionSource(QObject *parent)
55 : QGeoPositionInfoSource(parent),
56 logFile(new QFile(this)),
57 timer(new QTimer(this))
58{
59 connect(sender: timer, SIGNAL(timeout()), receiver: this, SLOT(readNextPosition()));
60
61 logFile->setFileName(":/simplelog.txt");
62 if (!logFile->open(flags: QIODevice::ReadOnly))
63 qWarning() << "Error: cannot open source file" << logFile->fileName();
64}
65
66QGeoPositionInfo LogFilePositionSource::lastKnownPosition(bool /*fromSatellitePositioningMethodsOnly*/) const
67{
68 return lastPosition;
69}
70
71LogFilePositionSource::PositioningMethods LogFilePositionSource::supportedPositioningMethods() const
72{
73 return AllPositioningMethods;
74}
75
76int LogFilePositionSource::minimumUpdateInterval() const
77{
78 return 500;
79}
80
81void LogFilePositionSource::startUpdates()
82{
83 int interval = updateInterval();
84 if (interval < minimumUpdateInterval())
85 interval = minimumUpdateInterval();
86
87 timer->start(msec: interval);
88}
89
90void LogFilePositionSource::stopUpdates()
91{
92 timer->stop();
93}
94
95void LogFilePositionSource::requestUpdate(int /*timeout*/)
96{
97 // For simplicity, ignore timeout - assume that if data is not available
98 // now, no data will be added to the file later
99 if (logFile->canReadLine())
100 readNextPosition();
101 else
102 emit updateTimeout();
103}
104
105void LogFilePositionSource::readNextPosition()
106{
107 QByteArray line = logFile->readLine().trimmed();
108 if (!line.isEmpty()) {
109 QList<QByteArray> data = line.split(sep: ' ');
110 double latitude;
111 double longitude;
112 bool hasLatitude = false;
113 bool hasLongitude = false;
114 QDateTime timestamp = QDateTime::fromString(s: QString(data.value(i: 0)), f: Qt::ISODate);
115 latitude = data.value(i: 1).toDouble(ok: &hasLatitude);
116 longitude = data.value(i: 2).toDouble(ok: &hasLongitude);
117
118 if (hasLatitude && hasLongitude && timestamp.isValid()) {
119 QGeoCoordinate coordinate(latitude, longitude);
120 QGeoPositionInfo info(coordinate, timestamp);
121 if (info.isValid()) {
122 lastPosition = info;
123 emit positionUpdated(update: info);
124 }
125 }
126 }
127}
128
129QGeoPositionInfoSource::Error LogFilePositionSource::error() const
130{
131 return QGeoPositionInfoSource::NoError;
132}
133

source code of qtlocation/examples/positioning/logfilepositionsource/logfilepositionsource.cpp