tennisclient.cpp Example File

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 #include "tennisclient.h"

 #include <qbluetoothsocket.h>

 #include <QtCore/QDataStream>
 #include <QtCore/QByteArray>

 #include <QtCore/QStringList>

 TennisClient::TennisClient(QObject *parent)
 :   QObject(parent), socket(0), stream(0), elapsed(new QTime), lagTimeout(0)
 {
     lagTimer.setInterval(1000);
     connect(&lagTimer, SIGNAL(timeout()), this, SLOT(sendEcho()));
 }

 TennisClient::~TennisClient()
 {
     stopClient();
 }

 void TennisClient::startClient(const QBluetoothServiceInfo &remoteService)
 {
     if (socket)
         return;

     serviceInfo = remoteService;

     // Connect to service
     socket = new QBluetoothSocket(QBluetoothSocket::L2capSocket);
     qDebug() << "Create socket";
     socket->connectToService(remoteService);
     qDebug() << "ConnecttoService done";

     connect(socket, SIGNAL(readyRead()), this, SLOT(readSocket()));
     connect(socket, SIGNAL(connected()), this, SLOT(connected()));
     connect(socket, SIGNAL(disconnected()), this, SIGNAL(disconnected()));
     connect(socket, SIGNAL(disconnected()), this, SLOT(socketDisconnected()));
     connect(socket, SIGNAL(error(QBluetoothSocket::SocketError)), this, SLOT(error(QBluetoothSocket::SocketError)));

     lagTimer.start();
 }

 void TennisClient::stopClient()
 {
     if (socket == 0) // already stopped
         return;

     qDebug() << Q_FUNC_INFO << "closing client!";

     lagTimer.stop();

     delete stream;
     stream = 0;

     socket->deleteLater();
     socket = 0;
 }

 void TennisClient::socketDisconnected()
 {
     qDebug() << "Got socketDisconnected";
     stopClient();
 }

 void TennisClient::readSocket()
 {
     if (!socket)
         return;

     while (socket->bytesAvailable()) {
         QString str;

         *stream >> str;

         QStringList args = str.split(QChar(' '));
         QString s = args.takeFirst();

         if (s == "m" && args.count() == 2) {
             emit moveBall(args.at(0).toInt(), args.at(1).toInt());
         }
         else if (s == "s" && args.count() == 2){
             emit score(args.at(0).toInt(), args.at(1).toInt());
         }
         else if (s == "l" && args.count() == 1){
             emit moveLeftPaddle(args.at(0).toInt());
         }
         else if (s == "e"){ // echo
             QByteArray b;
             QDataStream s(&b, QIODevice::WriteOnly);
             s << str;
             socket->write(b);
         }
         else if (s == "E"){
             lagTimeout = 0;
             QTime then = QTime::fromString(args.at(0), "hh:mm:ss.zzz");
             if (then.isValid()) {
                 emit lag(then.msecsTo(QTime::currentTime()));
 //                qDebug() << "RTT: " << then.msecsTo(QTime::currentTime()) << "ms";
             }
         }
         else {
             qDebug() << Q_FUNC_INFO << "Unknown command" << str;
         }
     }
 }

 void TennisClient::moveRightPaddle(int y)
 {
     int msec = elapsed->elapsed();

     if (stream && msec > 50) {
         QByteArray b;
         QDataStream s(&b, QIODevice::WriteOnly);
         s << QString("r %1").arg(y);
         socket->write(b);
         elapsed->restart();
     }
 }

 void TennisClient::connected()
 {
     stream = new QDataStream(socket);
     emit connected(socket->peerName());
 }

 void TennisClient::error(QBluetoothSocket::SocketError err)
 {
     qDebug() << "Got socket error" <<Q_FUNC_INFO << "error" << err;
     emit disconnected();
 }

 void TennisClient::sendEcho()
 {
     if (lagTimeout) {
         lagTimeout--;
         return;
     }

     if (stream) {
         QByteArray b;
         QDataStream s(&b, QIODevice::WriteOnly);
         s << QString("E %1").arg(QTime::currentTime().toString("hh:mm:ss.zzz"));
         socket->write(b);
         lagTimeout = 10;
     }
 }