1 /*

     2 * Copyright (c) 2008-2009 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 #ifndef _MGLXDATASOURCE_H_

    21 #define _MGLXDATASOURCE_H_

    22 

    23 // INCLUDES

    24 #include <e32cmn.h>

    25 #include "mglxdatasourceupdateobserver.h"

    26 #include "mglxdatasourcerequestobserver.h"

    27 

    28 // FORWARD DECLARATIONS

    29 class CGlxRequest;

    30 

    31 // CONSTANTS

    32 

    33 // CLASS DECLARATION

    34 

    35 /**

    36  *  MGlxDataSource class 

    37  *

    38  *  Data Source  collates Data Source information.

    39  *  @lib GlxDataSource.lib

    40  *	@ingroup collection_component_design

    41  *  @internal reviewed 11/07/2007 by Dave Schofield

    42  */

    43 class MGlxDataSource 

    44 	{

    45 public:

    46 	/**

    47 	 * Asynchronous call to retrieve 

    48 	 * 

    49 	 * @param aListId list for this query relates to

    50 	 * @return error code

    51 	 */

    52 	virtual void DataSourceRequestL(CGlxRequest* aRequest, MGlxDataSourceRequestObserver& aObserver) = 0;

    53 	/**

    54 	 * Cancel asynchronous request call

    55 	 * as each requestor can only have one active request the observer is sufficient to cancel the request.

    56 	 * 

    57 	 */

    58 	virtual void CancelRequest(MGlxDataSourceRequestObserver& aObserver) = 0;

    59 public:

    60 

    61 	/**

    62 	 * Since there should be only one data source manager for a server,

    63 	 * clients can use this function to either create the instance or 

    64 	 * return the pointer if the instance already exists.

    65 	 *

    66 	 * The pointers are reference counter, and the instance is deleted after

    67 	 * there are no more clients. It is, therefore, necessary

    68 	 * to release the instance by calling Close() when no longer needed.

    69 	 *

    70 	 * @returns a pointer to a new or existing list manager instance

    71 	 */

    72 	IMPORT_C static MGlxDataSource* OpenDataSourceL(const TUid& aDataSource, MGlxDataSourceUpdateObserver& aObserver);

    73 	

    74 

    75 	/**

    76 	 * Decrements the reference count of the data source manager. Deletes the 

    77 	 * data source manager if there are no more references.

    78 	 */

    79 	virtual void Close(MGlxDataSourceUpdateObserver& aObserver)=0;

    80 	};

    81 

    82 

    83 

    84 #endif //_MGLXDATASOURCE_H_