C++ QDBusInterface::lastError方法代码示例

void quitApplicationsOverDBus()
{
    QDBusConnection connection = QDBusConnection::sessionBus();
    QDBusConnectionInterface *bus = connection.interface();
    const QStringList services = bus->registeredServiceNames();
    foreach (const QString &service, services) {
        if (service.startsWith(QLatin1String("org.freedesktop.DBus")) || service.startsWith(QLatin1Char(':'))) {
            continue;
        }
        QDBusInterface *iface = new QDBusInterface(service,
                QLatin1String("/MainApplication"),
                QLatin1String("org.kde.KApplication"),
                connection);
        if (!iface->isValid()) {
            if (verbose) {
                fprintf(stderr, "invalid interface of service %s\n", service.toLatin1().data());
            }
            continue;
        }
        iface->call("quit");
        if (iface->lastError().isValid()) {
            if (verbose) {
                fprintf(stderr, "killing %s with result\n", iface->lastError().message().toLatin1().data());
            }
        }
        delete iface;
    }
}

int main(int argc, char *argv[])
{
    // TODO: Clean this up, update API, etc.
    if (argc < 5 || argc > 6)
    {
        qWarning() << "Error detected! Insufficient number of arguments.";
        qWarning() << "";
        qWarning() << "Usage: ambdbusaccess <R/W> <Object> <Property> <Zone> [Value]";
        qWarning() << "- <R/W>";
        qWarning() << "  Used for specifying [R]ead or [W]rite.";
        qWarning() << "- <Object>";
        qWarning() << "  The AMB object to access.";
        qWarning() << "- <Property>";
        qWarning() << "  The property within the object to access.";
        qWarning() << "- <Zone>";
        qWarning() << "  The AMB zone to access.";
        qWarning() << "- [Value]";
        qWarning() << "  The value to write, if writing.";
        qWarning() << "Example: ambdbusaccess Write ClimateControl FanSpeedLevel 0 7";
        qWarning() << "";
        qWarning() << "This program returns an int under the following conditions:";
        qWarning() << "Successful Read: <Value Read>";
        qWarning() << "Unsuccessful Read: -1";
        qWarning() << "Successful Write: <Value Written>";
        qWarning() << "Unsuccessful Write: -1";

        return -1;
    }

    // TODO: Error check input.
    bool read = !strncmp(argv[1], "R", 1);
    QString object = argv[2];
    QString property = argv[3];
    qint32 zone = atoi(argv[4]);
    qint32 value = 0;

    if (argc == 6)
    {
        value = atoi(argv[5]);
    }

    // Necessary to suppress Qt messages about touching the D-Bus before the application was created.
    QCoreApplication a(argc, argv);

    // Sanity check that the system bus is actually present.
    if (!QDBusConnection::systemBus().isConnected())
    {
        qCritical() << "Could not access system D-Bus!";
        return -1;
    }

    // Get ahold of the manager object.
    QDBusInterface *manager = new QDBusInterface("org.automotive.message.broker", "/", "org.automotive.Manager",
                                                 QDBusConnection::systemBus());

    // Go fetch the path for the AMB object we are concerned with.
    qDebug().nospace() << "Looking for property " << property.toStdString().c_str() << " of object " <<
                          object.toStdString().c_str() << " in zone " << zone << ".";
    QDBusReply<QDBusObjectPath> propertyPath = manager->call("FindObjectForZone", object.toStdString().c_str(), zone);
    if (!propertyPath.isValid())
    {
        qDebug() << "Invalid reply!" << propertyPath.error() << "Got the path:" << propertyPath.value().path();
    }

    // Now that we have the path, open an interface to the object.
    QDBusInterface *propertyInterface = new QDBusInterface("org.automotive.message.broker", propertyPath.value().path(),
                                                           "org.automotive.ClimateControl", QDBusConnection::systemBus());

    // Perform our read or write operation.
    if (read)
    {
        QVariant reply = propertyInterface->property(property.toStdString().c_str());
        if (!reply.isValid())
        {
            qDebug() << "Invalid reply when reading the property!" << propertyInterface->lastError() << "Property:" <<
                        reply.toString();
            value = -1;
        }
        else
        {
            qDebug().nospace() << "Got a valid reply for the property of " << reply.toString().toStdString().c_str() << ".";
            value = reply.toInt();
        }
    }
    else
    {
        QVariant reply = propertyInterface->setProperty(property.toStdString().c_str(), value);
        if (reply.toBool())
        {
            qDebug() << "Successfully wrote the property.";
        }
        else
        {
            qDebug() << "Failed to write the property.";
            value = -1;
        }
    }

    // Clean up.
    delete propertyInterface;
//.........这里部分代码省略.........