Game Programming using Qt 5 Beginner's Guide - Second Edition

Time for action – Detecting a disconnect

When a client terminates the connection, we have to delete the socket from the local m_clients list. The socket's disconnected() signal is already connected to the removeConnection() slot, so we just need to implement it as follows:

void TcpServer::removeConnection()
{
    QTcpSocket *socket = qobject_cast<QTcpSocket*>(sender());
    if (!socket) {
        return;
    }
    ui->log->appendPlainText(tr("* Connection removed: %1, port %2\n")
                             .arg(socket->peerAddress().toString())
                             .arg(socket->peerPort()));
    m_clients.removeOne(socket);
    m_receivedData.remove(socket);
    socket->deleteLater();
    ui->disconnectClients->setEnabled(!m_clients.isEmpty());
}