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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
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** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
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** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
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****************************************************************************/

/*!
\example logfilepositionsource
\title Log File Position Source (C++)
\ingroup qtpositioning-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 position data from a text file, \e log.txt. The file specifies position
data using a simple text format: it contains one position 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 /^\}/
*/