1/* 2 * Copyright 2011-2012 Haiku, Inc. All rights reserved. 3 * Distributed under the terms of the MIT License. 4 * 5 * Authors: 6 * Axel Dörfler, axeld@pinc-software.de 7 * John Scipione, jscipione@gmail.com 8 * Oliver Tappe, zooey@hirschkaefer.de 9 * 10 * Corresponds to: 11 * headers/os/locale/Catalog.h hrev45083 12 * src/kits/locale/Catalog.cpp hrev45083 13 */ 14 15 16/*! 17 \file Catalog.h 18 \ingroup locale 19 \ingroup libbe 20 \brief Provides the BCatalog class. 21*/ 22 23 24/*! 25 \class BCatalog 26 \ingroup locale 27 \ingroup libbe 28 \brief String localization handling. 29 30 BCatalog is the class that allows you to perform string localization. This 31 means you give it a string in english, and it automatically returns the 32 translation of this string in the user's specified language, if available. 33 34 Most of the time, you don't have to deal with BCatalog directly. You use 35 the translation macros instead. However, there are some cases where you 36 will have to use catalogs directly. These include : 37 - Tools for managing catalogs : if you want to add, remove or edit 38 entries in a catalog, you need to do it using the BCatalog class. 39 - Accessing catalogs other than your own : the macros only grant you 40 access to the catalog linked with your application. To access 41 other catalogs (for example if you create a script interpreter and 42 want to localize the scripts), you will have to open a catalog 43 associated with your script. 44 45 \section macros Using the macros 46 You don't have to do much in your program to handle catalogs. You must 47 first set the B_TRANSLATION_CONTEXT define to a string that identifies which 48 part of the application the strings you will translate are in. This allows 49 the translators to keep track of the strings in the catalog more easily, 50 and find where they are visible in the application. then, all you have to 51 do, is enclose any string you want to make translatable in the 52 B_TRANSLATE() macro. This macro has two uses, it will allow your text to 53 be replaced at run-time by the proper localized one, but it will also 54 allow to build the base catalog, the one that you will send to the 55 translator team, from your sourcecode. 56 57 \section chaining Chaining of catalogs 58 The catalogs you get from the locale kit are designed to use a fallback 59 system so that the user get strings in the language he's the most fluent 60 with, depending on what catalogs are available. 61 62 For example, if the user sets his language preferences as french(France), 63 spanish, english, when an application loads a catalog, the following rules 64 are used: 65 - Try to load a french(France) catalog. If it is found, this catalog 66 will automatically include strings from the generic french catalog. 67 - Try to load a generic french catalog. 68 - Try to load a generic spanish catalog. 69 - Try to load a generic english catalog. 70 - If all of them failed, use the strings that are in the source code. 71 72 Note that french(France) will failback to french, but then directly to the 73 language in the source code. This avoids mixing 3 or more languages in the 74 same application if the catalogs are incomplete and avoids confusion. 75*/ 76 77 78/*! 79 \fn BCatalog::BCatalog() 80 \brief Construct an empty BCatalog object. 81 82 Should be followed by SetTo() method to set the catalog. 83*/ 84 85 86/*! 87 \fn BCatalog::BCatalog(const entry_ref& catalogOwner, const char* language, 88 uint32 fingerprint) 89 \brief Construct a BCatalog object for the given \a catalogOwner. 90 91 If you don't specify a language, the system default list will be used. 92 The language is passed here as a 2 letter ISO code. 93 94 The fingerprint is a way to check that the catalog that will be loaded 95 matches the current version of the application. A catalog made for a 96 different version of the application can be loaded if you set the 97 fingerprint to \c 0. This is usually not a problem, it only means that 98 some strings may not be translated properly. But if you want to provide 99 different versions of your application, it may be useful to separate their 100 catalogs. 101 102 \param catalogOwner entry_ref for which to load a catalog. 103 \param language The language of the catalog to load. If \c NULL, the user 104 settings will be used. 105 \param fingerprint The fingerprint version-info for the catalog to load. 106 If \c 0, the fingerprint will not be checked,and any version of the 107 catalog will be loaded. 108*/ 109 110 111/*! 112 \fn BCatalog::~BCatalog() 113 \brief Destroys the BCatalog object freeing memory used by it. 114*/ 115 116 117/*! 118 \fn const char* BCatalog::GetString(const char* string, 119 const char* context, const char* comment) 120 \brief Get a string from the catalog. 121 122 This method access the data of the catalog and reeturns you the translated 123 version of the string. You must pass it the context where the string is, as 124 the same string may appear somewhere else and need a differnet translation. 125 The comment is optional. It is meant as an help to translators, when the 126 string alone is not helpful enough or there are special things to note. 127 The comment is also used as a way to uniquely identify a string, so if two 128 identical strings share the same context, it is still possible to provide 129 different translations. 130 131 \param string The string to translate. 132 \param context The context where the string is located. 133 \param comment Supplementary comment for translators. 134 135 \returns The translated string, or the one passed as a parameter if no 136 translation was found. 137*/ 138 139 140/*! 141 \fn const char* BCatalog::GetString(uint32 id) 142 \brief Get a string by id from the catalog. 143 144 The id based version of this method is slightly faster, as it doesn't 145 have to compute the hash from the 3 parameters. However, it will fail 146 if there is an hash collision, so you should still fallback to the first 147 one in case of problems. Also note that the hash value may be different 148 from one catalog to another, depending on the file format they are stored 149 in, so you shouldn't rely on this method unless you are sure you can keep 150 all the catalog files under control. 151 152 \param id The identifier of the string. 153 154 \returns The translated string if found, or an empty string. 155*/ 156 157 158/*! 159 \fn status_t BCatalog::GetData(const char* name, BMessage* msg) 160 \brief Get custom data from the catalog. 161 162 This method allows you to localize something else than raw text. This 163 may include pictures, sounds, videos, or anything else. Note there is no 164 support for generating a catalog with such data inside, and the current 165 format may not support it. If you need to localize data that is not text, 166 it is advised to handle it by yourself. 167 168 \param name The name of the data to retrieve. 169 \param msg The BMessage to fill in with the data. 170 171 \returns A status code. 172 \retval B_OK Everything went fine. 173 \retval B_ERROR Unable to get an exclusive lock on data. 174 \retval B_NO_INIT Catalog is \c NULL. 175 \retval B_NAME_NOT_FOUND catalog with the specified \a name could not be 176 found. 177*/ 178 179 180/*! 181 \fn status_t BCatalog::GetData(uint32 id, BMessage* msg) 182 \brief Get custom data from the catalog. 183 184 As for GetString, the id-based version may be subject to hash-collisions, 185 but is faster. 186 187 Note the current catalog format doesn't allow storing custom data in 188 catalogs, so the only way to use this method is providing your own 189 catalog add-on for storing the data. 190*/ 191 192 193/*! 194 \fn status_t BCatalog::GetSignature(BString* sig) 195 \brief Get the catalog mime-signature. 196 197 This method fills the sig string with the mime-signature associated to the 198 catalog. 199 200 \param sig The string where to copy the signature. 201 202 \returns An error code. 203*/ 204 205 206/*! 207 \fn status_t BCatalog::GetLanguage(BString* lang) 208 \brief Get the catalog language. 209 210 This method fills the lang string with the language name for the catalog. 211 212 \param lang The string where to copy the language. 213 214 \returns An error code. 215 \retval B_OK Everything went as expected. 216 \retval B_ERROR Could not get exclusive lock on catalog. 217 \retval B_BAD_VALUE \a lang is \c NULL. 218 \retval B_NO_INIT Catalog data is \c NULL. 219*/ 220 221 222/*! 223 \fn status_t BCatalog::GetFingerprint(uint32* fp) 224 \brief Get the catalog fingerprint. 225 226 This method setsfp to the fingerprint of the catalog. This allows you 227 to check which version of the sourcecode this catalog was generated from. 228 229 \param fp The integer to set to the fingerprint value. 230 231 \returns An error code. 232 \retval B_OK Everything went as expected. 233 \retval B_ERROR Could not get exclusive lock on catalog. 234 \retval B_BAD_VALUE \a fp is \c NULL. 235 \retval B_NO_INIT Catalog data is \c NULL. 236*/ 237 238 239/*! 240 \fn status_t BCatalog::SetTo(const entry_ref& catalogOwner, 241 const char* language, uint32 fingerprint) 242 \brief Reload the string data. 243 244 This method reloads the data for the given signature and fingerprint. 245 246 \param catalogOwner The \c entry_ref of the catalog that you want to load. 247 \param language The language of the catalog to load. If \c NULL, the user 248 settings will be used. 249 \param fingerprint The fingerprint of the catalog you want to load. 250 251 \returns A status code, \c B_OK on success, \c B_ERROR on error. 252*/ 253 254 255/*! 256 \fn status_t BCatalog::InitCheck() const 257 \brief Check if the catalog is in a valid and usable state. 258 259 \returns A status code. 260 \retval B_OK The catalog is initialized properly. 261 \retval B_ERROR Could not get exclusive lock on catalog. 262 \retval B_NO_INIT Catalog data is \c NULL. 263*/ 264 265 266/*! 267 \fn int32 BCatalog::CountItems() const 268 \brief Gets the number of items in the catalog. 269 270 \returns the number of strings in the catalog or 0 on error. 271*/ 272