/*

* Copyright (c) 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:

* Declaration of CSsmPsKeyObserver class.

*

*/

#ifndef SSMPSKEYOBSERVER_H

#define SSMPSKEYOBSERVER_H

#include <e32base.h>

#include <e32property.h>

/**

*  An active object which waits until a P&S key value changes to a predefined

*  value and then signals a request status.

*/

NONSHARABLE_CLASS( CSsmPsKeyObserver ) : public CActive

    {

public:

    /**

    * First phase constructor.

    *

    * @param aCategory The UID that identifies the property category.

    * @param aKey The property sub-key, i.e. the key that identifies the

    *             specific property within the category.

    */

    CSsmPsKeyObserver( TUid aCategory, TUint aKey );

    /**

    * Destructor.

    */

    virtual ~CSsmPsKeyObserver();

    /**

    * Start observing the key value.

    *

    * @param aStatus Request status to be completed when the property reaches

    *        the target value.

    */

    void StartObserving( TRequestStatus& aStatus );

private:

    /**

    * From CActive.

    * Implements cancellation of an outstanding request.

    */

    virtual void DoCancel();

    /**

    * From CActive.

    * Handles an active object’s request completion event.

    */

    virtual void RunL();

protected:

    virtual TBool IsMatch( const TInt aKeyValue ) const = 0;

private:

    /**

    * Check the key value fron P&S and subscribe to listen to changes

    * in the P&S key if the value is not the same as the target value.

    */

    void CheckKeyValue();

    /**

    * Complete client request with the given error code.

    *

    * @param aErrorCode The error code to complete the request with.

    */

    void Complete( const TInt aErrorCode );

private: // data

    /** P&S variable to listen to. */

    RProperty iProperty;

    /** The UID that identifies the property category. */

    TUid iCategory;

    /**

    * The property sub-key, i.e. the key that identifies the specific property

    * within the category.

    */

    TUint iKey;

    /**

    * Request status to be completed when the property reaches the target value.

    */

    TRequestStatus* iClientStatus;

    };

#endif // SSMPSKEYOBSERVER_H