--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/devencdiskutils/DevEncStarter/inc/DevEncStarterPropertyObserver.h	Tue Jan 26 15:20:08 2010 +0200
@@ -0,0 +1,150 @@
+/*
+* Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:  
+*
+*/
+
+
+#ifndef DEVENCSTARTERPROPERTYOBSERVER_H
+#define DEVENCSTARTERPROPERTYOBSERVER_H
+
+// INCLUDES
+#include <e32base.h>
+#include <e32property.h>
+
+// CLASS DECLARATION
+
+/**
+ * MDevEncStarterPropertyChangeObserver
+ * Abstract interface for handling property change events.
+ **/
+
+class MDevEncStarterPropertyChangeObserver
+    {
+    public:
+        /**
+         * This is a callback function which is called when a property value is changed.
+         * @param aObserver a refference to the observer interface implementer
+         * @param aCategory UID of Publish And Subscribe category
+         * @param aKey subkey to specify the category event; to be used with Publish And Subscribe
+         * @param aValue the new value
+         * Event enumerations and uid:s of Publish And Subscribe can be found from PSVariables.h
+         **/
+        virtual void HandlePropertyChangeL( const TUid& aCategory,
+                                            const TUint aKey,
+                                            const TInt aValue ) = 0;
+
+        /**
+         * This is a callback function which is called when a P&S components returns an error
+         * @param aCategory UID of Publish And Subscribe category
+         * @param aKey subkey to specify the category event
+         * @param aError an error code
+         **/
+        virtual void HandlePropertyChangeErrorL( const TUid& aCategory,
+                                                 const TUint aKey,
+                                                 TInt aError ) = 0;
+    };
+
+// INCLUDES
+
+// CONSTANTS
+
+// CLASS DECLARATION
+
+/**
+ * Observer class that observes changes of Property values and propogates them further.
+ * The class defines a handle to a property, a single data value representing
+ * an item of state information.
+ *
+ **/
+class CDevEncStarterPropertyObserver : public CActive
+	{
+public:  // Constructors and destructor
+
+    /**
+     * Two-phased constructor.
+     * @param aObserver a reference to the observer interface implementer
+     * @param aCategory UID of Publish And Subscribe category
+     * @param aKey subkey to specify the category event; to be used with Publish And Subscribe
+     * Event enumerations and uid:s of Publish And Subscribe can be found from PSVariables.h
+     **/
+    static CDevEncStarterPropertyObserver* NewL( MDevEncStarterPropertyChangeObserver& aObserver,
+                                            const TUid& aCategory,
+                                            const TUint aKey );
+
+    /**
+     * Destructor.
+     **/
+    ~CDevEncStarterPropertyObserver();
+
+    /**
+     * Updates a value reference in correspondence with the current Property value
+     * @param handle to a value which will be updated
+     * @return KErrNone if operation was successful
+     **/
+	void GetValue( TInt& aValue ) const;
+
+ private:
+    /**
+     * C++ default constructor overload.
+     * Two-phased constructor.
+     * @param aObserver a reference to the observer interface implementer
+     * @param aCategory UID of Publish And Subscribe category
+     * @param aKey subkey to specify the category event; to be used with Publish And Subscribe
+     * Event enumerations and uid:s of Publish And Subscribe can be found from PSVariables.h
+     **/
+	CDevEncStarterPropertyObserver( MDevEncStarterPropertyChangeObserver& aObserver,
+	                           const TUid& aCategory,
+	                           const TUint aKey );
+
+    /**
+     * By default Symbian 2nd phase constructor is private.
+     **/
+    void ConstructL();
+
+ protected:  // Functions from base classes
+    /**
+     * From CActive
+     * Handles an active object’s request completion event
+     **/
+    void RunL();
+
+    /**
+     * From CActive,
+     * Cancels and outstanding request
+     **/
+    void DoCancel();
+
+ private:  // Data
+ 	// Value of a subscribed category property
+ 	TInt iValue;
+
+    // handle to Publish And Subscribe component
+    RProperty iProperty;
+
+    // Observer to be notified when particular Property value has changed
+    MDevEncStarterPropertyChangeObserver& iObserver;
+
+    // UID of Publish And Subscribe category
+    TUid iCategory;
+
+    // subkey to be used with Publish And Subscribe
+    TUint iKey;
+
+	};
+
+#endif  // CPROPERTYOBSERVER_H
+
+
+// End of File