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/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** GNU Free Documentation License
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms
** and conditions contained in a signed written agreement between you
** and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\example logfilepositionsource
\title Log File Position Source (C++)
\ingroup qtlocation-examples
\brief The Logfile Position Source shows how to create and work with a custom NMEA position source,
for platforms without GPS.
The data is read from a file which has positional data in NMEA format. The resulting time and
position information is then displayed to the screen as simple text in date/time and
latitude/longitude format.
This example class reads location data from a text file, \e log.txt. The file specifies location
data using a simple text format: it contains one location update per line, where each line contains
a date/time, a latitude and a longitude, separated by spaces. The date/time is in ISO 8601 format
and the latitude and longitude are in degrees decimal format. Here is an excerpt from \e log.txt:
\code
2009-08-24T22:25:01 -27.576082 153.092415
2009-08-24T22:25:02 -27.576223 153.092530
2009-08-24T22:25:03 -27.576364 153.092648
\endcode
The class reads this data and distributes it via the
\l{QGeoPositionInfoSource::positionUpdated()}{positionUpdated()} signal.
Here is the definition of the \c LogFilePositionSource class:
\quotefromfile logfilepositionsource/logfilepositionsource.h
\skipto class LogFilePositionSource
\printuntil };
The main methods overrided by the subclass are:
\list
\li \l{QGeoPositionInfoSource::startUpdates()}{startUpdates()}: called by client applications
to start regular position updates.
\li \l{QGeoPositionInfoSource::stopUpdates()}{stopUpdates()}: called by client applications to
stop regular position updates.
\li \l{QGeoPositionInfoSource::requestUpdate()}{requestUpdate()}: called by client applications
to request a single update, with a specified timeout.
\endlist
When a position update is available, the subclass emits the
\l{QGeoPositionInfoSource::positionUpdated()}{positionUpdated()} signal.
Here are the key methods in the class implementation:
\quotefromfile logfilepositionsource/logfilepositionsource.cpp
\skipto LogFilePositionSource::LogFilePositionSource
\printuntil /^\}/
\skipto LogFilePositionSource::startUpdates
\printuntil /^\}/
\skipto LogFilePositionSource::stopUpdates
\printuntil /^\}/
\skipto LogFilePositionSource::requestUpdate
\printuntil /^\}/
\printuntil LogFilePositionSource::readNextPosition
\printuntil /^\}/
*/
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