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:  Base class for thumbnail provider plug-ins

    15  *

    16 */

    17 

    18 

    19 #ifndef THUMBNAILPROVIDER_H

    20 #define THUMBNAILPROVIDER_H

    21 

    22 #include <ecom/ecom.h>

    23 #include <apmstd.h>

    24 

    25 #include "thumbnailmanager.h" // TThumbnailFlags

    26 #include "thumbnaillog.h"

    27 

    28 /**

    29  *  Thumbnail provider observer class

    30  *

    31  *  @since S60 v5.0

    32  */

    33 class MThumbnailProviderObserver

    34     {

    35 public:

    36     /**

    37      * Thumbnail provider observer callback to notify the server when

    38      * thumbnail has been generated.

    39      *

    40      * @since S60 5.0

    41      * @param aError Error code

    42      * @param aBitmap Thumbnail bitmap. The observer implementation will

    43      *                assume ownership of the bitmap.

    44      * @param aOriginalSize Original size of the object in pixels.

    45      * @param aEXIF ETrue if thumbnail origin is EXIF.

    46      */

    47     virtual void ThumbnailProviderReady( TInt aError, CFbsBitmap* aBitmap,

    48         const TSize& aOriginalSize, const TBool aEXIF, const TBool aPortrait  ) = 0;

    49 };

    50 

    51 

    52 /**

    53  *  Base class for thumbnail provider plug-ins.

    54  *

    55  *  @since S60 v5.0

    56  */

    57 class CThumbnailProvider: public CBase

    58     {

    59 public:

    60     /**

    61      * Create a provider instance. The instance is identified

    62      * by the implementation UID.

    63      */

    64     static CThumbnailProvider* NewL( TUid aUid );

    65 

    66     /**

    67      * Get the UID of this provider.

    68      *

    69      * @since S60 5.0

    70      * @return Provider implementation UID

    71      */

    72     TUid Uid();

    73 

    74     /**

    75      * Set the observer to receive notification

    76      * about thumbnail generation completion.

    77      *

    78      * @since S60 5.0

    79      * @param aObserver Reference to the observing object. Ownership not

    80      *                  transferred.

    81      */

    82     void SetObserver( MThumbnailProviderObserver& aObserver );

    83 

    84     /**

    85      * Set the target size for uncropped thumbnails. The actual thumbnail

    86      * at least this wide or high, depending on which is the limiting

    87      * factor.

    88      *

    89      * @since S60 5.0

    90      * @param aSize Target size in pixels for uncropped thumbnails.

    91      */

    92     void SetTargetSize( const TSize& aSize );

    93 

    94     /**

    95      * Set the target size for cropped thumbnails. The actual thumbnail

    96      * at least this large and it will include the whole thumbnail,

    97      * not just the cropped portion.

    98      *

    99      * @since S60 5.0

   100      * @param aCroppedSize Target size in pixels for cropped thumbnails.

   101      */

   102     void SetCroppedTargetSize( const TSize& aCroppedSize );

   103 

   104     /**

   105      * Reset thumbnail parameters to defaults.

   106      */

   107     void Reset();

   108 

   109     /**

   110      * Get thumbnail bitmap. Must be implemented by provider plug-ins.

   111      *

   112      * @since S60 5.0

   113      * @param aFs File server session that can be used

   114      * @param aFile File handle to the object file

   115      * @param aMimeType MIME-type of the object file.

   116      * @param aFlags Thumbnail generation flags

   117      * @param aDisplayMode Display mode

   118      */

   119     virtual void GetThumbnailL( RFs& aFs, RFile64& aFile, const TDataType&

   120         aMimeType, const CThumbnailManager::TThumbnailFlags aFlags, const

   121         TDisplayMode aDisplayMode, const CThumbnailManager::TThumbnailQualityPreference aQualityPreference ) = 0;

   122   

   123     /**

   124      * Get thumbnail bitmap. Must be implemented by provider plug-ins.

   125      *

   126      * @since S60 5.0

   127      * @param aFs File server session that can be used

   128      * @param aBuffer object buffer

   129      * @param aMimeType MIME-type of the object file.

   130      * @param aFlags Thumbnail generation flags

   131      * @param aDisplayMode Display mode

   132      */    

   133     virtual void GetThumbnailL( RFs& aFs, TDesC8* aBuffer, const

   134         TDataType& aMimeType, const CThumbnailManager::TThumbnailFlags aFlags,

   135         const TDisplayMode aDisplayMode, const CThumbnailManager::TThumbnailQualityPreference aQualityPreference  ) = 0;  

   136     

   137     /**

   138      * Get thumbnail bitmap. Must be implemented by provider plug-ins.

   139      *

   140      * @since S60 5.0

   141      * @param aFs File server session that can be used

   142      * @param aBuffer object buffer

   143      */

   144     

   145     virtual void GetThumbnailL( RFs& aFs, TDesC8& aBuffer) = 0;

   146 

   147     /**

   148      * Cancel a previous thumbnail request, if any.

   149      *

   150      * @since S60 5.0

   151      */

   152     virtual void CancelGetThumbnail() = 0;

   153 

   154     virtual ~CThumbnailProvider(){}

   155 

   156 protected:

   157     /**

   158      * Get the actual target size for the thumbnail.

   159      * This is the maximum of the non-cropped and cropped

   160      * target sizes.

   161      *

   162      * @since S60 5.0

   163      */

   164     inline void ResolveSize();

   165 

   166     /**

   167      * Calculate the scaled down size for the thumbnail.

   168      * Aspect ratio is always preserved. If cropping is disabled

   169      * the resulting size at most as wide or tall as requested.

   170      * If cropping is enabled, the result is at least as wide

   171      * and as tall as requested (unless original size is smaller

   172      * than requested).

   173      *

   174      * @since S60 5.0

   175      * @param aOriginalSize Original size in pixels

   176      * @param aTargetSize Target size in pixels

   177      * @param aCrop Enable cropping

   178      * @return Result size

   179      */

   180     inline TSize FitToSize( const TSize& aOriginalSize, const TSize&

   181         aTargetSize, TBool aCrop );

   182 

   183 protected:

   184     /**

   185      * Provider observer. Implemented by thumbnail generation task.

   186      * Not own.

   187      */

   188     MThumbnailProviderObserver* iObserver;

   189 

   190     /**

   191      * Thumbnail generation flags.

   192      */

   193     CThumbnailManager::TThumbnailFlags iFlags;

   194 

   195     /**

   196      * Thumbnail generation flags.

   197      */

   198     CThumbnailManager::TThumbnailQualityPreference iQualityPreference;

   199 

   200     /**

   201      * Size of the original object.

   202      */

   203     TSize iOriginalSize;

   204 

   205     /**

   206      * Target size for uncropped thumbnails.

   207      */

   208     TSize iTargetSize;

   209 

   210     /**

   211      * Target size for cropped thumbnails.

   212      */

   213     TSize iCroppedTargetSize;

   214 

   215     /**

   216      * Display mode for thumbnail bitmap

   217      */

   218     TDisplayMode iDisplayMode;

   219 

   220     /**

   221      * ECOM plug-in destructor key.

   222      */

   223     TUid iDtor_ID_Key;

   224 

   225     /**

   226      * UID of this implementation.

   227      */

   228     TUid iUid;

   229 };

   230 

   231 

   232 #endif // THUMBNAILPROVIDER_H