/*

* Copyright (c) 2006 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:  A Central Repository key observer class for Light Settings API.

*

*/

#ifndef SYSAPCENREPLIGHTSETTINGSOBSERVER_H

#define SYSAPCENREPLIGHTSETTINGSOBSERVER_H

#include <e32base.h>

#include <cenrepnotifyhandler.h>

class CSysApAppUi;

class CRepository;

class CCenRepNotifyHandler;

/**

* A Central Repostitory observer for getting notifications from Light Settings API.

*

* System Application monitors backlight timeout changes with this observer.

*

* @lib None.

* @since S60 3.2

*/

class CSysApCenRepLightSettingsObserver : public CBase, public MCenRepNotifyHandlerCallback

    {

public:

    /**

    * Symbian two-phased constructor.

    *

    * @since S60 3.2

    * @param aSysApAppUi    reference to System Application application UI class

    * @return a new CSysApCenRepLightSettingsObserver instance

    */ 

    static CSysApCenRepLightSettingsObserver* NewL( CSysApAppUi& aSysApAppUi );

    /**

    * Destructor.

    */

    virtual ~CSysApCenRepLightSettingsObserver();

public: // Other functions

    /**

    * Returns the lights timeout in seconds.

    *

    * @since S60 3.2

    * @return TInt lights timeout in seconds

    */         

    TInt GetLightsTimeout() const;

protected: // from MCenRepNotifyHandlerCallback

    /** 

    * This callback method is used to notify the client about

    * changes for integer value keys, i.e. key type is EIntKey.

    *

    * @param aId Id of the key that has changed.

    * @param aNewValue The new value of the key.

    */

    void HandleNotifyInt( TUint32 aId, TInt aNewValue );

    /** 

    * This callback method is used to notify the client about errors

    * in the handler. Any error in handling causes the handler to stop

    * handling any more notifications. Handling can be restarted with

    * a call to aHandler->StartListeningL(), if the error is non-fatal.

    * However, be careful to trap any errors from this call if this is done.

    *

    * @param aId Id of the key this instance listens for or if notifications for

    *            whole repository are listened, could also be KInvalidNotificationId.

    * @param aError Error code.

    * @param aHandler Pointer to the handler instance. 

    *                 This pointer can be used to identify the handler or restart the listening.

    */

    void HandleNotifyError( TUint32 aId, TInt error, CCenRepNotifyHandler* aHandler );

protected:

    /**

    * Constructor.

    * 

    * @since S60 3.2

    * @param aSysApAppUi    reference to System Application application UI class

    */

    CSysApCenRepLightSettingsObserver( CSysApAppUi& aSysApAppUi );

private:

    /**

    * C++ default constructor.

    * 

    * Usage not permitted.

    */

    CSysApCenRepLightSettingsObserver();

    /**

    * Copy constructor.

    *

    * By default, prohibit copy constructor.

    */

    CSysApCenRepLightSettingsObserver( const CSysApCenRepLightSettingsObserver& );

    /**

    * Symbian 2nd-phase constuctor.

    */

    void ConstructL();

    /**

    * Copy constructor.

    *

    * By default, Prohibit assigment operator.

    */

    CSysApCenRepLightSettingsObserver& operator= ( const CSysApCenRepLightSettingsObserver& );

private: // data

    /**

    * Reference to System Application's UI class.

    */

    CSysApAppUi& iSysApAppUi;

    /**

    * Central repository session.

    * Own.

    */    

    CRepository* iSession;

    /**

    * Notification handler for lights timeout key.

    * Own.

    */ 

    CCenRepNotifyHandler* iDisplayLightsTimeoutHandler;

    };

#endif // SYSAPCENREPLIGHTSETTINGSOBSERVER_H