1 /*

     2 * Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:

    15 *

    16 */

    17 

    18 

    19 

    20 

    21 /**

    22  @file

    23  @internalTechnology 

    24 */

    25 

    26 #ifndef HWRMPSCHANGEOBSERVER_H

    27 #define HWRMPSCHANGEOBSERVER_H

    28 

    29 // INCLUDES

    30 #include <e32base.h>

    31 #include <e32property.h>

    32 

    33 // FORWARD DECLARATIONS

    34 // None

    35 

    36 /**

    37 *  An interface the developer implements for handling notification events. 

    38 *

    39 */

    40 class MHWRMPSChangeObserver

    41     {    

    42     public:

    43         

    44         /** 

    45         * Called when the PS value changes.

    46         * Note that if the value changes

    47         * very rapidly, some state transitions might be missed.

    48         * It is however guaranteed that latest state is always obtained.

    49         *

    50         * @param aUid Uid of the changed property

    51         * @param aKey Property identifier

    52         * @param aValue Indicates latest value

    53 		*/

    54         virtual void PSValueChanged(const TUid& aUid, TUint32 aKey, TInt aValue) = 0;

    55 	};

    56 

    57 /**

    58 * Active object wrapper for Publish and Subscribe one-shot notification handling.

    59 * Listens for changes in light status and notifies the client.

    60 *

    61 */

    62 class CHWRMPSChangeObserver : public CActive

    63     {

    64     public:

    65 

    66         /**

    67         * This is a two-phase constructor method that is used to

    68         * create a new instance of CHWRMPSChangeObserver.

    69         * A newly created instance immediately starts listening to PS value changes.

    70         *

    71         * @param aCallback Reference to a callback instance.

    72         * @param aUid Uid of the changed property

    73         * @param aKey Property identifier

    74         * @return          A pointer to a new instance of the CHWRMPSChangeObserver class.

    75         */

    76         static CHWRMPSChangeObserver* NewL(MHWRMPSChangeObserver& aCallback,

    77                                       const TUid& aUid,

    78                                       TUint32 aKey);

    79 

    80         /**

    81         * This is a two-phase constructor method that is used to

    82         * create a new instance of CHWRMPSChangeObserver.

    83         * A newly created instance immediately starts listening to PS value changes.

    84         * Leaves the constructed instance to cleanup stack. 

    85         *

    86         * @param aCallback Reference to a callback instance.

    87         * @param aUid Uid of the changed property

    88         * @param aKey Property identifier

    89         * @return          A pointer to a new instance of the CHWRMPSChangeObserver class.

    90         */

    91         static CHWRMPSChangeObserver* NewLC(MHWRMPSChangeObserver& aCallback,

    92                                       const TUid& aUid,

    93                                       TUint32 aKey);

    94 

    95         /**

    96         * Destructor.

    97         */

    98         virtual ~CHWRMPSChangeObserver();

    99 

   100     protected:

   101 

   102         // From CActive

   103         void RunL();

   104         TInt RunError(TInt aError);

   105         void DoCancel();

   106 

   107     private:

   108 

   109         /**

   110         * Constructor

   111         *

   112         * @param aCallback Reference to a callback instance.

   113         * @param aUid Uid of the changed property

   114         * @param aKey Property identifier

   115         */

   116         CHWRMPSChangeObserver(MHWRMPSChangeObserver& aCallback,

   117                               const TUid& aUid,

   118                               TUint32 aKey);

   119                                                    

   120         /**

   121         * By default Symbian 2nd phase constructor is private.

   122         */

   123         void ConstructL();

   124 

   125         /*

   126         * Order notification

   127         */

   128         void OrderNotification();

   129        

   130     private:

   131         

   132         MHWRMPSChangeObserver& iCallback;       // not owned by this class

   133         RProperty              iProperty;       // P&S property

   134         TUid                   iUid;            // Uid of the property

   135         TUint32                iKey;            // Property identifier

   136 

   137     };

   138 

   139 #endif      // HWRMVIBRASTATUSOBSERVER_H

   140 

   141 // End of File