refs #409 permanent plugin storage

src/blackmisc/pluginstorageprovider.h

@@ -0,0 +1,69 @@
+/* Copyright (C) 2015
+ * swift project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+//! \file
+
+#ifndef BLACKMISC_PLUGINSTORAGEPROVIDER_H
+#define BLACKMISC_PLUGINSTORAGEPROVIDER_H
+
+#include "blackmisc/variant.h"
+#include <QObject>
+
+namespace BlackMisc
+{
+
+    //! Interface for a plugin storage provider.
+    //! It allows plugins to store any arbitrary data which can be packed into a \sa CVariant
+    //! Every plugin shall have its own data area. This means mulitple plugins can store
+    //! data under the same key without overwriting each other.
+    class IPluginStorageProvider
+    {
+
+    public:
+
+        //! Destructor
+        virtual ~IPluginStorageProvider() {}
+
+        //! Get plugin data stored for object and identified by key
+        virtual CVariant getPluginData(const QObject *obj, const QString& key) const = 0;
+
+        //! Store plugin data for object, identified by key and packed into value
+        virtual void setPluginData(const QObject *obj, const QString& key, const CVariant &value) = 0;
+    };
+
+    //! Delegating class which can be directly used to access an \sa IPluginStorageProvider instance
+    class CPluginStorageAware
+    {
+    public:
+        //! \copydoc IPluginStorageProvider::getPluginData
+        virtual CVariant getPluginData(const QObject *obj, const QString& key) const
+        {
+            return m_pluginStorageProvider->getPluginData(obj, key);
+        }
+
+        //! \copydoc IOwnAircraftProvider::ownAircraft
+        virtual void setPluginData(const QObject *obj, const QString& key, const CVariant &value)
+        {
+            m_pluginStorageProvider->setPluginData(obj, key, value);
+        }
+
+
+    protected:
+        //! Constructor
+        CPluginStorageAware(IPluginStorageProvider *pluginStorageProvider) :
+            m_pluginStorageProvider(pluginStorageProvider)
+        {
+            Q_ASSERT(pluginStorageProvider);
+        }
+        IPluginStorageProvider *m_pluginStorageProvider = nullptr; //!< access to object
+    };
+
+} // namespace
+
+#endif