WebSockets MQTT 订阅范例

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#ifndef CLIENTSUBSCRIPTION_H
#define CLIENTSUBSCRIPTION_H
#include "websocketiodevice.h"
#include <QtCore/QObject>
#include <QtMqtt/QMqttClient>
#include <QtWebSockets/QWebSocket>
class ClientSubscription : public QObject
{
    Q_OBJECT
public:
    ClientSubscription(QObject *parent = nullptr);
    void setUrl(const QUrl &url); // ie ws://broker.hivemq.com:8000/mqtt
    void setTopic(const QString &topic);
    void setVersion(int v);
signals:
    void messageReceived(QByteArray);
    void errorOccured();
public slots:
    void connectAndSubscribe();
    void handleMessage(const QByteArray &msgContent);
private:
    QMqttClient m_client;
    QMqttSubscription *m_subscription;
    QUrl m_url;
    QString m_topic;
    WebSocketIODevice m_device;
    int m_version;
};
#endif // CLIENTSUBSCRIPTION_H