lp-data-transfer/modules/MQTTClient/MQTTClient.h

#ifndef Mqtt_H
#define Mqtt_H
#pragma once
// #include "qmqtt.h"
#include <qmqtt_client.h>
#include <QObject>
#include <functional>
//回调函数，注意：为了防止复制（深拷贝），多处使用了右值引用&&
// typedef void (mqttCallbackFn)(QString &&topic, QByteArray &&payload);
using MQTTCallbackFn = std::function<void(const QString& topic, const QByteArray&payload)>;
//调用例子
//void subCbFunc(QString &&topic, QByteArray &&payload)
//{
//    qDebug()<< "sub cb func" << topic << payload;
//}
//mqtt->subscribe(topic, subCbFunc);

class MQTTClient : public QObject
{
    Q_OBJECT

public:
    explicit MQTTClient(QObject *parent = 0);
    ~MQTTClient();

    //void regCallback(mqttCallbackFn *func);                   //通配符订阅公共回调
    void subscribe(const QString& topic, MQTTCallbackFn&func);        //单一主题分开回调，通配符为公共回调
    void publish(const QString &topic, const QByteArray &payload);         //发布主题
    void connect2Host(const QString& host, const uint16_t port, const QString& usr, const QString& passwd, const QString& clientID);

public slots:
    void onReceived(const QMQTT::Message& message);         //收到数据后发送到回调

private:
    QMQTT::Client *mqtt;
    // QString host = "192.168.9.6";
    // quint16 port = 1883;
    // QString userName = "admin";
    // QString password = "N6pNXbZjspDRqNGnxMmc";

    MQTTCallbackFn shareCbFunc;                  //共享回调
    QHash<QString, MQTTCallbackFn> hCbFuncs;               //独立回调集

};

#endif // Mqtt_H