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/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtMqtt module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
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** accordance with the commercial license agreement provided with the
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** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
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** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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****************************************************************************/
/*!
\example quicksubscription
\title Quick MQTT Example
\ingroup qtmqtt-examples
\brief Registering QMqttClient to QML and using it in a Qt Quick user
interface.
\image quicksubscription.png
\e {Quick MQTT} demonstrates how to register QMqttClient as a QML type and
use it in a Qt Quick application.
\l {Qt MQTT} does not provide a QML API in its current version. However,
you can make the C++ classes of the module available to QML.
\section1 Creating a Client
We create a \c QmlMqttClient class with the QMqttClient class as a base
class:
\quotefromfile quicksubscription/qmlmqttclient.cpp
\skipto QmlMqttClient(
\printuntil }
We use the \c subscribe() function to create a subscription object:
\printuntil }
We connect to QMqttSubscription::messageReceived( ) to receive all messages
sent to the broker:
\printuntil }
We use an QMqttMessage object to store the payload of a received
message:
\skipto handleMessage
\printuntil }
\section1 Registering Classes in QML
In the \c main.cpp file, we register the \c QmlMqttClient class as a
QML type, MqttClient:
\quotefromfile quicksubscription/main.cpp
\skipto main(int
\printuntil qmlRegisterType
In addition, we register the \c QmlMqttSubscription class as an uncreatable
type:
\printuntil qmlRegisterUncreatableType
We can now use the MqttClient type in the \c main.qml file to create an
MQTT client:
\quotefromfile quicksubscription/main.qml
\skipto MqttClient {
\printuntil }
*/
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