// Copyright (c) 2007-2009 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:

//

/**

 @file

 @internalTechnology 

*/

#ifndef PSPOPERTYOBSERVER_H

#define PSPOPERTYOBSERVER_H

#include <e32base.h>

#include <e32property.h>

/**

* Callback interface for property change notification.

*/

class MPsPropertyObserver

    {

public:

    /**

    * Notifies changes in the property value

    *

    * @param aKey key for which value changed.

    * @param aValue new value.

    * @param aError KErrNone if successful. otherwise on of system-wide error.

    */

    virtual void PsPropertyChanged(TInt aKey, TInt aValue, TInt aError) =0;

    };

/**

*  This class observes changes in PS-Property value.

*

*/

NONSHARABLE_CLASS(CPsPropertyObserver) : public CActive

    {

public:

    IMPORT_C static CPsPropertyObserver* NewL(const TUid& aGroup, TInt aKey, MPsPropertyObserver& aObserver);

    IMPORT_C static TInt Get(const TUid& aGroup, TInt aKey, TInt& value);

    IMPORT_C TInt Get(TInt& value);

    void Start();

    ~CPsPropertyObserver();

private:

    CPsPropertyObserver(TUid aGroup, TInt aKey, MPsPropertyObserver& aObserver);

    void ConstructL(const TUid& aGroup);

protected:

    void RunL();

    void DoCancel();

private:

    RProperty iProperty;

    TUid iGroup;

    TInt iKey;

    TInt iValue;

    MPsPropertyObserver& iObserver;

    };

#endif