Qt 5.11 | Qt Core | Local Fortune Server Example | server.cpp Example File

Qt 5.11.3 Reference Documentation

# server.cpp Example File

ipc/localfortuneserver/server.cpp

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      #include <QtWidgets>
      #include <QtNetwork>

      #include <stdlib.h>

      #include "server.h"
      #include <qlocalserver.h>
      #include <qlocalsocket.h>

      Server::Server(QWidget *parent)
          : QDialog(parent)
      {
          setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);

          server = new QLocalServer(this);
          if (!server->listen("fortune")) {
              QMessageBox::critical(this, tr("Local Fortune Server"),
                                    tr("Unable to start the server: %1.")
                                    .arg(server->errorString()));
              close();
              return;
          }

          QLabel *statusLabel = new QLabel;
          statusLabel->setWordWrap(true);
          statusLabel->setText(tr("The server is running.\n"
                                  "Run the Local Fortune Client example now."));

          fortunes << tr("You've been leading a dog's life. Stay off the furniture.")
                   << tr("You've got to think about tomorrow.")
                   << tr("You will be surprised by a loud noise.")
                   << tr("You will feel hungry again in another hour.")
                   << tr("You might have mail.")
                   << tr("You cannot kill time without injuring eternity.")
                   << tr("Computers are not intelligent. They only think they are.");

          QPushButton *quitButton = new QPushButton(tr("Quit"));
          quitButton->setAutoDefault(false);
          connect(quitButton, &QPushButton::clicked, this, &Server::close);
          connect(server, &QLocalServer::newConnection, this, &Server::sendFortune);

          QHBoxLayout *buttonLayout = new QHBoxLayout;
          buttonLayout->addStretch(1);
          buttonLayout->addWidget(quitButton);
          buttonLayout->addStretch(1);

          QVBoxLayout *mainLayout = new QVBoxLayout(this);
          mainLayout->addWidget(statusLabel);
          mainLayout->addLayout(buttonLayout);

          setWindowTitle(QGuiApplication::applicationDisplayName());
      }

      void Server::sendFortune()
      {
          QByteArray block;
          QDataStream out(&block, QIODevice::WriteOnly);
          out.setVersion(QDataStream::Qt_5_10);
          const int fortuneIndex = QRandomGenerator::global()->bounded(0, fortunes.size());
          const QString &message = fortunes.at(fortuneIndex);
          out << quint32(message.size());
          out << message;

          QLocalSocket *clientConnection = server->nextPendingConnection();
          connect(clientConnection, &QLocalSocket::disconnected,
                  clientConnection, &QLocalSocket::deleteLater);

          clientConnection->write(block);
          clientConnection->flush();
          clientConnection->disconnectFromServer();
      }