lp-data-alarm/MQTTAgent/widget.cpp

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);

    mqtt = new QMQTT::Client();

    connect(mqtt, &QMQTT::Client::connected, []{
        qDebug()<< "connected";
    });
    connect(mqtt, &QMQTT::Client::disconnected, []{
        qDebug()<< "disconnect";
    });
    connect(mqtt, &QMQTT::Client::received, this, &Widget::onReceived);

    mqtt->setHostName("y.kjxry.cn");
    //mqtt->setHostName("mq.tongxinmao.com"); //18830
    //mqtt->setHostName("www.kjxry.cn");
    mqtt->setPort(port);
    mqtt->setKeepAlive(60);
    mqtt->setClientId("C001"); //唯一id, 相同id不能同时连接
    mqtt->setUsername(userName);
    mqtt->setPassword(password.toUtf8());

    mqtt->setAutoReconnect(true); //开启自动重连
    mqtt->setCleanSession(true); //非持久化连接，上线时，将不再关心之前所有的订阅关系以及离线消息

    mqtt->setVersion(QMQTT::V3_1_1);
    qDebug()<< "ver" << mqtt->version();

    mqtt->connectToHost();
}

Widget::~Widget()
{
    delete ui;
}

//接收到的消息
void Widget::onReceived(const QMQTT::Message& message)
{
    qDebug() << "recv" << message.topic() << message.payload();
}

void Widget::on_pushButton_2_clicked()
{
    //不同的订阅方式
    //mqtt->subscribe("alarm/led", 1);
    //mqtt->subscribe("+/led", 1);
    mqtt->subscribe("alarm/#", 1);
}

void Widget::on_pushButton_3_clicked()
{
    //QMQTT::Message message(i, EXAMPLE_TOPIC, QString("Number %1").arg(i).toUtf8());
    QMQTT::Message message;
    message.setTopic(topic);
    message.setPayload("test");
    message.setRetain(true); //保留最后一条数据

    mqtt->publish(message);
}