1 /*

     2 * Copyright (c) 2007-2008 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:    The event observer interface

    15  *

    16 */

    17 

    18 

    19 

    20 

    21 #ifndef __MSHWENGINEOBSERVER_H__

    22 #define __MSHWENGINEOBSERVER_H__

    23 

    24 // INCLUDES

    25 #include <e32std.h>

    26 #include <e32base.h>

    27 

    28 // CLASS DECLARATION

    29 

    30 /**

    31  *  MShwEventObserver

    32  */

    33 class MShwEngineObserver

    34 	{

    35 	protected:

    36 	

    37 		/**

    38 		 * Destructor. Dont allow deleting objects through this interface.

    39 		 */

    40 		virtual ~MShwEngineObserver() {};

    41 

    42 	public: // the API

    43 

    44 		/**

    45 		 * This notification is called once the engine is started,

    46 		 * meaning that the slideshow is running.

    47 		 */

    48 		virtual void EngineStartedL() = 0;

    49 

    50 		/**

    51 		 * This notification is called once the engine is paused,

    52 		 * meaning that the slideshow is frozen.

    53 		 */

    54 		virtual void EnginePausedL() = 0;

    55 

    56 		/**

    57 		 * This notification is called once the engine is resumed,

    58 		 * meaning that the slideshow is re-running after a pause

    59 		 */

    60 		virtual void EngineResumedL() = 0;

    61 		

    62 		/**

    63          * This notification is called once the selection key, EngineLSKPressedL

    64          * pressed.

    65          */

    66         virtual void EngineToggleUiStateL() = 0;

    67         

    68         /**

    69          * LSk pressed.

    70          */

    71         virtual void EngineLSKPressedL() = 0;

    72 

    73         /**

    74          * This notification is called when there is such an error during 

    75          * slideshow that it cannot continue, for example all items got removed.

    76          * This method is allowed to leave, in which case slideshow engine panics

    77          * with EEngineFatalError. This is ok as in case of error all we can do is

    78          * try to exit slideshow, either easy way or hard way :)

    79          * @exception EEngineFatalError if this method does leave.

    80          */

    81         virtual void ErrorDuringSlideshowL() = 0;

    82 

    83 	};

    84 

    85 #endif // __MSHWENGINEOBSERVER_H__