complexping.cpp Example File

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  #include <stdio.h>

  #include <QtCore/QCoreApplication>
  #include <QtCore/QFile>
  #include <QtCore/QDebug>
  #include <QtCore/QProcess>
  #include <QtDBus/QtDBus>

  #include "ping-common.h"
  #include "complexping.h"

  void Ping::start(const QString &name)
  {
      if (name != SERVICE_NAME)
          return;

      // open stdin for reading
      qstdin.open(stdin, QIODevice::ReadOnly);

      // find our remote
      iface = new QDBusInterface(SERVICE_NAME, "/", "org.example.QtDBus.ComplexPong.Pong",
                                 QDBusConnection::sessionBus(), this);
      if (!iface->isValid()) {
          fprintf(stderr, "%s\n",
                  qPrintable(QDBusConnection::sessionBus().lastError().message()));
          QCoreApplication::instance()->quit();
      }

      connect(iface, SIGNAL(aboutToQuit()), QCoreApplication::instance(), SLOT(quit()));

      while (true) {
          printf("Ask your question: ");

          QString line = QString::fromLocal8Bit(qstdin.readLine()).trimmed();
          if (line.isEmpty()) {
              iface->call("quit");
              return;
          } else if (line == "value") {
              QVariant reply = iface->property("value");
              if (!reply.isNull())
                  printf("value = %s\n", qPrintable(reply.toString()));
          } else if (line.startsWith("value=")) {
              iface->setProperty("value", line.mid(6));
          } else {
              QDBusReply<QDBusVariant> reply = iface->call("query", line);
              if (reply.isValid())
                  printf("Reply was: %s\n", qPrintable(reply.value().variant().toString()));
          }

          if (iface->lastError().isValid())
              fprintf(stderr, "Call failed: %s\n", qPrintable(iface->lastError().message()));
      }
  }

  int main(int argc, char **argv)
  {
      QCoreApplication app(argc, argv);

      if (!QDBusConnection::sessionBus().isConnected()) {
          fprintf(stderr, "Cannot connect to the D-Bus session bus.\n"
                  "To start it, run:\n"
                  "\teval `dbus-launch --auto-syntax`\n");
          return 1;
      }

      QDBusServiceWatcher serviceWatcher(SERVICE_NAME, QDBusConnection::sessionBus(),
                                         QDBusServiceWatcher::WatchForRegistration);

      Ping ping;
      QObject::connect(&serviceWatcher, &QDBusServiceWatcher::serviceRegistered,
                       &ping, &Ping::start);

      QProcess pong;
      pong.start("./complexpong");

      app.exec();
  }