Implemented availability control for gstreamer player backend

Change-Id: I6d736b90ad59e258eb6f20befea8cfe1afce423a
Reviewed-by: Michael Goddard <michael.goddard@nokia.com>
Reviewed-by: Jonas Rabbe <jonas.rabbe@nokia.com>

src/plugins/gstreamer/mediaplayer/qgstreameravailabilitycontrol.cpp

@@ -0,0 +1,66 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the Qt Toolkit.
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+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
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+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
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+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
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+** GNU General Public License Usage
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+** Public License version 3.0 as published by the Free Software Foundation
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+****************************************************************************/
+
+#include "qgstreameravailabilitycontrol.h"
+#include <private/qmediaresourceset_p.h>
+
+QT_BEGIN_NAMESPACE
+
+QGStreamerAvailabilityControl::QGStreamerAvailabilityControl(
+        QMediaPlayerResourceSetInterface *resources, QObject *parent)
+    : QMediaAvailabilityControl(parent)
+    , m_resources(resources)
+{
+    Q_ASSERT(m_resources);
+    connect(m_resources, SIGNAL(availabilityChanged(bool)), this, SLOT(handleAvailabilityChanged()));
+}
+
+void QGStreamerAvailabilityControl::handleAvailabilityChanged()
+{
+    emit availabilityChanged(this->availability());
+}
+
+QtMultimedia::AvailabilityError QGStreamerAvailabilityControl::availability() const
+{
+    return m_resources->isAvailable() ? QtMultimedia::NoError : QtMultimedia::BusyError;
+}
+
+QT_END_NAMESPACE