1 /*

     2 * Copyright (c) 2007 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 #ifndef DEVENCSTARTERPROPERTYOBSERVER_H

    20 #define DEVENCSTARTERPROPERTYOBSERVER_H

    21 

    22 // INCLUDES

    23 #include <e32base.h>

    24 #include <e32property.h>

    25 

    26 // CLASS DECLARATION

    27 

    28 /**

    29  * MDevEncStarterPropertyChangeObserver

    30  * Abstract interface for handling property change events.

    31  **/

    32 

    33 class MDevEncStarterPropertyChangeObserver

    34     {

    35     public:

    36         /**

    37          * This is a callback function which is called when a property value is changed.

    38          * @param aObserver a refference to the observer interface implementer

    39          * @param aCategory UID of Publish And Subscribe category

    40          * @param aKey subkey to specify the category event; to be used with Publish And Subscribe

    41          * @param aValue the new value

    42          * Event enumerations and uid:s of Publish And Subscribe can be found from PSVariables.h

    43          **/

    44         virtual void HandlePropertyChangeL( const TUid& aCategory,

    45                                             const TUint aKey,

    46                                             const TInt aValue ) = 0;

    47 

    48         /**

    49          * This is a callback function which is called when a P&S components returns an error

    50          * @param aCategory UID of Publish And Subscribe category

    51          * @param aKey subkey to specify the category event

    52          * @param aError an error code

    53          **/

    54         virtual void HandlePropertyChangeErrorL( const TUid& aCategory,

    55                                                  const TUint aKey,

    56                                                  TInt aError ) = 0;

    57     };

    58 

    59 // INCLUDES

    60 

    61 // CONSTANTS

    62 

    63 // CLASS DECLARATION

    64 

    65 /**

    66  * Observer class that observes changes of Property values and propogates them further.

    67  * The class defines a handle to a property, a single data value representing

    68  * an item of state information.

    69  *

    70  **/

    71 class CDevEncStarterPropertyObserver : public CActive

    72 	{

    73 public:  // Constructors and destructor

    74 

    75     /**

    76      * Two-phased constructor.

    77      * @param aObserver a reference to the observer interface implementer

    78      * @param aCategory UID of Publish And Subscribe category

    79      * @param aKey subkey to specify the category event; to be used with Publish And Subscribe

    80      * Event enumerations and uid:s of Publish And Subscribe can be found from PSVariables.h

    81      **/

    82     static CDevEncStarterPropertyObserver* NewL( MDevEncStarterPropertyChangeObserver& aObserver,

    83                                             const TUid& aCategory,

    84                                             const TUint aKey );

    85 

    86     /**

    87      * Destructor.

    88      **/

    89     ~CDevEncStarterPropertyObserver();

    90 

    91     /**

    92      * Updates a value reference in correspondence with the current Property value

    93      * @param handle to a value which will be updated

    94      * @return KErrNone if operation was successful

    95      **/

    96 	void GetValue( TInt& aValue ) const;

    97 

    98  private:

    99     /**

   100      * C++ default constructor overload.

   101      * Two-phased constructor.

   102      * @param aObserver a reference to the observer interface implementer

   103      * @param aCategory UID of Publish And Subscribe category

   104      * @param aKey subkey to specify the category event; to be used with Publish And Subscribe

   105      * Event enumerations and uid:s of Publish And Subscribe can be found from PSVariables.h

   106      **/

   107 	CDevEncStarterPropertyObserver( MDevEncStarterPropertyChangeObserver& aObserver,

   108 	                           const TUid& aCategory,

   109 	                           const TUint aKey );

   110 

   111     /**

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

   113      **/

   114     void ConstructL();

   115 

   116  protected:  // Functions from base classes

   117     /**

   118      * From CActive

   119      * Handles an active object’s request completion event

   120      **/

   121     void RunL();

   122 

   123     /**

   124      * From CActive,

   125      * Cancels and outstanding request

   126      **/

   127     void DoCancel();

   128 

   129  private:  // Data

   130  	// Value of a subscribed category property

   131  	TInt iValue;

   132 

   133     // handle to Publish And Subscribe component

   134     RProperty iProperty;

   135 

   136     // Observer to be notified when particular Property value has changed

   137     MDevEncStarterPropertyChangeObserver& iObserver;

   138 

   139     // UID of Publish And Subscribe category

   140     TUid iCategory;

   141 

   142     // subkey to be used with Publish And Subscribe

   143     TUint iKey;

   144 

   145 	};

   146 

   147 #endif  // CPROPERTYOBSERVER_H

   148 

   149 

   150 // End of File