kservicetypetrader.h

Go to the documentation of this file.

/* This file is part of the KDE libraries
   Copyright (C) 2000 Torben Weis <weis@kde.org>
   Copyright (C) 2006 David Faure <faure@kde.org>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License version 2 as published by the Free Software Foundation.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/
#ifndef __kservicetypetrader_h__
#define __kservicetypetrader_h__

#include "kservice.h"

class KDECORE_EXPORT KServiceTypeTrader
{
public:
    ~KServiceTypeTrader();

    KService::List query( const QString& servicetype,
                          const QString& constraint = QString() ) const;

    KService::List defaultOffers( const QString& serviceType,
                                  const QString& constraint = QString() ) const;
    KService::Ptr preferredService( const QString & serviceType ) const;

    static KServiceTypeTrader* self();

    template <class T>
    static T *createInstanceFromQuery(const QString &serviceType,
            const QString &constraint = QString(), QObject *parent = 0,
            const QVariantList &args = QVariantList(), QString *error = 0)
    {
        return createInstanceFromQuery<T>(serviceType, 0, parent, constraint, args, error);
    }

    template <class T>
    static T *createInstanceFromQuery(const QString &serviceType,
            QWidget *parentWidget, QObject *parent, const QString &constraint = QString(),
            const QVariantList &args = QVariantList(), QString *error = 0)
    {
        const KService::List offers = self()->query(serviceType, constraint);
        Q_FOREACH (const KService::Ptr &ptr, offers) {
            T *component = ptr->template createInstance<T>(parentWidget, parent, args, error);
            if (component) {
                if (error)
                    error->clear();
                return component;
            }
        }
        if (error)
            *error = i18n("No service matching the requirements was found");
        return 0;
    }

#ifndef KDE_NO_DEPRECATED
    template <class T>
    static KDE_DEPRECATED T *createInstanceFromQuery(const QString &serviceType, const QString &constraint,
            QObject *parent, const QStringList &args, int *error = 0)
    {
        const KService::List offers = KServiceTypeTrader::self()->query(serviceType, constraint);
        if (offers.isEmpty()) {
            if (error) {
                *error = KLibLoader::ErrNoServiceFound;
            }
            return 0;
        }

        return KService::createInstance<T>(offers.begin(), offers.end(), parent, args, error);
    }
#endif


    static void applyConstraints( KService::List& lst,
                                  const QString& constraint );

private:
    KServiceTypeTrader();

    // dissalow copy ctor and assignment operator
    KServiceTypeTrader( const KServiceTypeTrader& other );
    KServiceTypeTrader& operator=( const KServiceTypeTrader& rhs );

    class Private;
    Private * const d;
};

#endif