1 /*

     2 * Copyright (c) 2006-2007 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:  ?Description

    15 *

    16 */

    17 

    18 

    19 #ifndef IRCHANGEOBSERVER_H

    20 #define IRCHANGEOBSERVER_H

    21 

    22 #include <e32base.h>

    23 #include <e32property.h>

    24 

    25 /**

    26  * MIRChangeObserver

    27  * Abstract interface for handling property change events.

    28  */

    29 class MIRChangeObserver

    30 	{

    31 	public:

    32 	/**

    33 	 * This is a callback function which is called when a property value of type int is changed.

    34 	 * @param aCategory UID of Publish And Subscribe category

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

    36 	 * @param aValue the new value

    37 	 */

    38 	 virtual void HandleChangeL(const TUid& aCategory, const TUint aKey, 

    39 	 	const TInt aValue) = 0;

    40 	};

    41 

    42 

    43 // CLASS DECLARATION

    44 

    45 /**

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

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

    48  * an item of state information.

    49  *

    50  * @Code

    51  *

    52  * Updates an int value reference in correspondence 

    53  * with the current Property value

    54  * CIRObserver::GetValue(TInt& aValue)

    55  *

    56  * @endcode

    57  */

    58 class CIRObserver:public CActive

    59 	{

    60 public:

    61 	/**

    62      * Two-phased constructor.

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

    64      * @param aCategory UID of Publish And Subscribe category

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

    66      * @param aPropertyType property type to observe

    67      */

    68 	static CIRObserver* NewL(MIRChangeObserver& aObserver,const TUid& aCategory, 

    69 		const TUint aKey,const RProperty::TType aPropertyType);

    70 		

    71 	/**

    72      * Destructor.

    73      */	

    74 	~CIRObserver();

    75 	

    76 	/**

    77      * Updates an int value reference in correspondence with the current Property value

    78      * @param aValue handle to a value which will be updated

    79      */

    80 	void GetValue(TInt& aValue) const;

    81 	

    82 protected:  // Functions from base classes

    83 

    84     /**

    85      * From CActive

    86      * Handles an active object’s request completion event

    87      */

    88     void RunL();

    89 

    90     /**

    91      * From CActive, 

    92      * Cancels and outstanding request

    93      */

    94     void DoCancel();

    95 

    96 private:

    97 	/**

    98      * C++ default constructor.

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

   100      * @param aCategory UID of Publish And Subscribe category

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

   102      * @param aPropertyType property type to observe

   103      **/

   104 	CIRObserver(MIRChangeObserver& aObserver, const TUid& aCategory, 

   105 		const TUint aKey, const RProperty::TType aPropertyType);

   106 		

   107 	/**

   108      * default Symbian 2nd phase constructor.

   109      */

   110 	void ConstructL();

   111 	

   112 

   113 private:

   114 

   115 	//Value of a subscribed category property of type int.

   116  	TInt                        iValueInt;

   117 	

   118 	// handle to Publish And Subscribe component

   119     RProperty                   iProperty;

   120 

   121 	MIRChangeObserver&  iObserver;

   122     // UID of Publish And Subscribe category

   123     TUid                        iCategory;

   124     // subkey to be used with Publish And Subscribe

   125     TUint                       iKey;

   126     //Type of the observed property.

   127     RProperty::TType            iPropertyType;

   128 

   129 	};

   130 

   131 #endif // IRCHANGEOBSERVER_H