1 /*

     2 * Copyright (c) 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 * Declaration of CSsmPsKeyObserver class.

    16 *

    17 */

    18 

    19 #ifndef SSMPSKEYOBSERVER_H

    20 #define SSMPSKEYOBSERVER_H

    21 

    22 #include <e32base.h>

    23 #include <e32property.h>

    24 

    25 /**

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

    27 *  value and then signals a request status.

    28 */

    29 NONSHARABLE_CLASS( CSsmPsKeyObserver ) : public CActive

    30     {

    31 

    32 public:

    33 

    34     /**

    35     * First phase constructor.

    36     *

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

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

    39     *             specific property within the category.

    40     */

    41     CSsmPsKeyObserver( TUid aCategory, TUint aKey );

    42 

    43     /**

    44     * Destructor.

    45     */

    46     virtual ~CSsmPsKeyObserver();

    47 

    48     /**

    49     * Start observing the key value.

    50     *

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

    52     *        the target value.

    53     */

    54     void StartObserving( TRequestStatus& aStatus );

    55 

    56 private:

    57 

    58     /**

    59     * From CActive.

    60     * Implements cancellation of an outstanding request.

    61     */

    62     virtual void DoCancel();

    63 

    64     /**

    65     * From CActive.

    66     * Handles an active object’s request completion event.

    67     */

    68     virtual void RunL();

    69 

    70 protected:

    71 

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

    73 

    74 private:

    75 

    76     /**

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

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

    79     */

    80     void CheckKeyValue();

    81 

    82     /**

    83     * Complete client request with the given error code.

    84     *

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

    86     */

    87     void Complete( const TInt aErrorCode );

    88 

    89 private: // data

    90 

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

    92     RProperty iProperty;

    93 

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

    95     TUid iCategory;

    96 

    97     /**

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

    99     * within the category.

   100     */

   101     TUint iKey;

   102 

   103     /**

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

   105     */

   106     TRequestStatus* iClientStatus;

   107 

   108     };

   109 

   110 #endif // SSMPSKEYOBSERVER_H