epoc32/include/coneresloader.h
author William Roberts <williamr@symbian.org>
Wed, 31 Mar 2010 12:27:01 +0100
branchSymbian2
changeset 3 e1b950c65cb4
parent 0 061f57f2323e
child 4 837f303aceeb
permissions -rw-r--r--
Attempt to represent the S^2->S^3 header reorganisation as a series of "hg rename" operations
     1 /*
     2 * Copyright (c) 2002-2006 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 the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
     6 * which accompanies this distribution, and is available
     7 * at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
     8 *
     9 * Initial Contributors:
    10 * Nokia Corporation - initial contribution.
    11 *
    12 * Contributors:
    13 *
    14 * Description:  Cone Resource Loader API enables adding and removing 
    15 *                localized resource files into the CONE environment.
    16 *
    17 */
    18 
    19 
    20 #ifndef CONERESLOADER_H
    21 #define CONERESLOADER_H
    22 
    23 // forward declarations
    24 class CCoeEnv;
    25 
    26 /** 
    27 * Class encapsulates methods for opening and closing localised resource files
    28 * in the CONE environment. The actual reading of resources from an opened 
    29 * resource file is done using various CCoeEnv provided resource-reading 
    30 * methods. Cone Resource Loader API consist of the RConeResourceLoader class.
    31 *
    32 * Only one resource at a time may be open by one RConeResourceLoader instance. 
    33 * You can use several RConeResourceLoader instances for accessing several 
    34 * resources simultaneously or use one instance and close the previous resource
    35 * before opening a new one.
    36 *
    37 * The implementation uses BaflUtils::NearestLanguageFile to search for
    38 * a localised resource in proper search order.
    39 * 
    40 * Usage example:  
    41 *
    42 * @code
    43 *  #include <ConeResLoader.h>  
    44 *
    45 *  // Get CCoeEnv instance
    46 *  CEikonEnv* eikEnv = CEikonEnv::Static();
    47 *
    48 *  // Initialize loader
    49 *  RConeResourceLoader rLoader(eikEnv);
    50 *
    51 *  // Open resource file
    52 *  _LIT( KSampleResourceFileName, "Z:\\System\\Apps\\sample\\sample.rsc" );
    53 *  TFileName fileName(KSampleResourceFileName);
    54 *  rLoader.OpenL(fileName);
    55 *
    56 *  // Push resource loader to cleanup stack, so that it will always be properly 
    57 *  // closed when popped.
    58 *  CleanupClosePushL(rLoader);
    59 *
    60 *  // Read a resource   
    61 *  iSomeArray = eikEnv->ReadDesC16ArrayResourceL(R_SOME_RESOURCE);
    62 *
    63 *  // Pop and destroy rLoader from stack. 
    64 *  // This also calls close on rLoader since CleanupClosePushL was used.
    65 *  CleanupStack::PopAndDestroy(); // rLoader
    66 *
    67 * @endcode
    68 *
    69 * @lib commonengine.lib
    70 * @since S60 2.0
    71 */
    72 class RConeResourceLoader
    73     {
    74     public:
    75         /**
    76          * Constructor. 
    77          *
    78          * @param aEnv is a reference to Control environment in which resource
    79          * is loaded.
    80          */
    81         IMPORT_C RConeResourceLoader(CCoeEnv& aEnv);
    82 
    83         /**
    84          * Opens the resource file for reading. Only one resource may be open 
    85          * at a time. Panics if this instance already has a file open. 
    86          * The implementation uses BaflUtils::NearestLanguageFile to search 
    87          * for a localized resource file in proper search order.
    88          * 
    89          * @param aFileName is the resource file name to open. This parameter
    90          * value is changed to the best matching language file found. The drive
    91          * letter is required in the filename.
    92          * @return a Symbian OS error code.
    93          *
    94          * @panic KErrNotSupported The instance already has a file open.
    95          */
    96         IMPORT_C TInt Open(TFileName& aFileName);
    97 
    98         /**
    99          * Opens the resource file for reading. Only one resource may be open 
   100          * at a time. Leaves if this instance already has a file open.
   101          * The implementation uses BaflUtils::NearestLanguageFile to search
   102          * for a localized resource file in proper search order.
   103          * 
   104          * @param aFileName Reference for resource file name. Please
   105          *                  note that drive letter is required ! 
   106          *
   107          * @leave KErrNotSupported The instance already has a file open.
   108          */
   109         IMPORT_C void OpenL(TFileName& aFileName);
   110 
   111 
   112         /**
   113          * Closes the opened resource file, if one is open. Does nothing if no
   114          * file has been opened. New resource file may be opened after the 
   115          * previous has been closed. Always remember to close the resource when 
   116          * finished using it.
   117          */
   118         IMPORT_C void Close();
   119 
   120     private:
   121                 
   122         // Prohibit copy constructor and assigment operator because not deriving from CBase.
   123         RConeResourceLoader(const RConeResourceLoader&);
   124         RConeResourceLoader& operator= ( const RConeResourceLoader& );
   125     
   126         // Needed for closing
   127         CCoeEnv& iEnv; 
   128         TInt iResourceFileOffset;
   129     };
   130 
   131 
   132 #endif
   133 
   134 // End of File