Qt 5.9 | Qt Network | Network Chat Example | connection.h Example File

Qt 5.9.9 Reference Documentation

# connection.h Example File

network-chat/connection.h

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      #ifndef CONNECTION_H
      #define CONNECTION_H

      #include <QHostAddress>
      #include <QString>
      #include <QTcpSocket>
      #include <QTime>
      #include <QTimer>

      static const int MaxBufferSize = 1024000;

      class Connection : public QTcpSocket
      {
          Q_OBJECT

      public:
          enum ConnectionState {
              WaitingForGreeting,
              ReadingGreeting,
              ReadyForUse
          };
          enum DataType {
              PlainText,
              Ping,
              Pong,
              Greeting,
              Undefined
          };

          Connection(QObject *parent = 0);

          QString name() const;
          void setGreetingMessage(const QString &message);
          bool sendMessage(const QString &message);

      signals:
          void readyForUse();
          void newMessage(const QString &from, const QString &message);

      protected:
          void timerEvent(QTimerEvent *timerEvent) override;

      private slots:
          void processReadyRead();
          void sendPing();
          void sendGreetingMessage();

      private:
          int readDataIntoBuffer(int maxSize = MaxBufferSize);
          int dataLengthForCurrentDataType();
          bool readProtocolHeader();
          bool hasEnoughData();
          void processData();

          QString greetingMessage;
          QString username;
          QTimer pingTimer;
          QTime pongTime;
          QByteArray buffer;
          ConnectionState state;
          DataType currentDataType;
          int numBytesForCurrentDataType;
          int transferTimerId;
          bool isGreetingMessageSent;
      };

      #endif