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:   Definition of MHuiBitmapProvider, an interface that provides 

    15 *                a bitmap and its alpha mask when requested. 

    16 *

    17 */

    18 

    19 

    20 

    21 #ifndef __HUIBITMAPPROVIDER_H__

    22 #define __HUIBITMAPPROVIDER_H__

    23 

    24 class CFbsBitmap;

    25 

    26 /** 

    27  * MHuiBitmapProvider is an interface that provides a bitmap and its alpha 

    28  * mask when requested.

    29  * 

    30  * By storing MHuiBitmapProviders in the CHuiTextureManager we can delete and 

    31  * regenerate the textures used by the toolkit as needed - enabling improved 

    32  * use of memory resource, such as when the application goes to background.

    33  * In this case, when we want to restore all the textures, we may just recall 

    34  * the providers to reload the textures. 

    35  *

    36  * Typically, control classes would implement the ProvideBitmapL method of this

    37  * class, which would handle all the loading or generation needed to produce the

    38  * bitmaps stored by the TextureManager.

    39  * 

    40  * A provider should exist as long as the associated texture is stored within

    41  * the texture manager.

    42  */

    43 class MHuiBitmapProvider 

    44     {

    45 public:

    46 

    47     IMPORT_C virtual ~MHuiBitmapProvider();

    48             

    49     /**

    50      * Provide a bitmap and mask from the given UID.

    51      * This method should create a bitmap and its mask, usually by loading it from disk.

    52      *

    53      * @param aId      TextureManager id of this bitmap, may be used for extracting

    54      *                 an icon resource.

    55      * @param aBitmap  Output parameter for the provider: On return, has to store 

    56      *                 a pointer to the generated bitmap. Ownership transferred to caller.

    57 	 *                 The support for input CFbsBitmap formats varies between 

    58 	 *                 different renderers. See \ref cfbsbitmapsupport 

    59 	 *                 Table describing renderer bitmap support.      

    60 	 * @param aMaskBitmap  

    61 	 *                 Output parameter for the provider: On return, has to store 

    62      *                 a pointer to the generated alpha mask or <code>NULL</code> 

    63      * 				   if there is no mask. Ownership of the bitmap is transferred 

    64      *                 to the caller.

    65      * 

    66      * @see CHuiTextureManager::CreateTextureL()

    67      */

    68      virtual void ProvideBitmapL(TInt aId, CFbsBitmap*& aBitmap, CFbsBitmap*& aMaskBitmap) = 0;

    69     

    70     };

    71 

    72 

    73 #endif // __HUIBITMAPPROVIDER_H__