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1// Copyright (C) 2023 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
3
4/*!
5 \page qtlinguist-index.html
6 \title Qt Linguist Manual
7 \ingroup qttools
8 \ingroup internationalization
9 \brief Using Qt translation tools: lupdate, lrelease, and \QL.
10
11 \startpage {index.html}{Qt Reference Documentation}
12 \nextpage Release managers
13
14 \keyword Qt Linguist
15
16 Release managers, translators, and developers can use Qt tools to translate
17 Qt C++ and Qt Quick applications into local languages.
18
19 In addition to the Qt translation file (TS) format, \QL and \c lupdate
20 support XML Localization Interchange File Format (XLIFF).
21
22 \table
23 \row
24 \li \inlineimage front-publishing.png
25 \li \inlineimage front-ui.png
26 \li \inlineimage front-coding.png
27 \row
28 \li \l{Release managers}
29 \li \l{Translators}
30 \li \l{Developers}
31 \row
32 \li
33 \list
34 \li \l {Creating translation files}
35 \li \l {Using lupdate}
36 \li \l {Using lrelease}
37 \li \l {Using lconvert}
38 \li \l {Using lcheck}
39 \endlist
40 \li
41 \list
42 \li \l {Qt Linguist user interface}
43 \li \l {Translating strings}
44 \li \l {Selecting context or label to translate}
45 \li \l {Selecting strings to translate}
46 \li \l {Viewing strings in context}
47 \li \l {Reusing translations}
48 \li \l {Validating translations}
49 \li \l {Translating multiple languages simultaneously}
50 \endlist
51 \li
52 \list
53 \li \l{TS file format}
54 \li \l{Text ID based translations}
55 \li \l{Meta strings reference}
56 \li \l{CMake Commands in Qt6 LinguistTools}{CMake commands}
57 \li \l{Examples}
58 \endlist
59 \endtable
60
61 The following video shows how to internationalize and localize a simple
62 example application:
63
64 \youtube xNIz78IPBu0
65*/
66
67/*!
68 \page linguist-toc.html
69 \title All topics
70
71 \list
72 \li \l{Release managers}
73 \list
74 \li \l {Creating translation files}
75 \li \l {Using lupdate}
76 \li \l {Using lrelease}
77 \endlist
78 \li \l{Translators}
79 \list
80 \li \l {Qt Linguist user interface}
81 \li \l {Translating strings}
82 \li \l {Selecting context or label to translate}
83 \li \l {Selecting strings to translate}
84 \li \l {Viewing strings in context}
85 \li \l {Reusing translations}
86 \li \l {Validating translations}
87 \li \l {Translating multiple languages simultaneously}
88 \endlist
89 \li \l{Developers}
90 \list
91 \li \l{TS file format}
92 \li \l{Text ID based translations}
93 \li \l{Meta strings reference}
94 \li \l{CMake Commands in Qt6 LinguistTools}{CMake commands}
95 \li \l{Examples}
96 \endlist
97 \endlist
98 */
99
100/*!
101 \page linguist-manager.html
102 \title Release managers
103
104 \previouspage Qt Linguist Manual
105 \nextpage Creating translation files
106
107 \image front-publishing.png
108
109 Release managers use \c lupdate to generate a set of translation source (TS)
110 files from the application source files (QML and C++) and pass them to
111 translators. The translators use \QL to translate the strings and pass the
112 TS files back to the release managers. They use \c lrelease to generate
113 compact versions of the TS files, called Qt message (QM) files, that are
114 ready for use by the application.
115
116 \list
117 \li \l {Creating translation files}
118 \li \l {Using lupdate}
119 \li \l {Using lrelease}
120 \endlist
121
122 You can use the tools in repeated cycles as applications change and evolve.
123 They preserve existing translations and make it easy to identify new strings.
124 In addition, you can use the \QL phrase books to consistently translate
125 multiple applications and projects.
126
127 You can configure CMake projects to automatically run \c lupdate and
128 \c lrelease when you build a project and generate TS and QM files for you.
129
130 You can use the Qt Design Studio
131 \l{https://doc-snapshots.qt.io/qtdesignstudio/studio-translations.html}
132 {Translations} view to test and manage \l {Text ID based translations}
133 {ID-based translations}.
134*/
135
136/*!
137 \page linguist-creating-ts-files.html
138
139 \previouspage Release managers
140 \nextpage Using lupdate
141
142 \title Creating translation files
143
144 Most of the text to translate in an application consists of either single
145 words or short phrases. These typically appear as window titles, menu
146 items, tooltips, and labels to buttons, check boxes, and radio buttons.
147
148 Developers mark the phrases as translatable in the QML and C++ source code.
149 The Qt tools provide context information for each of the phrases to help the
150 translator understand their meaning. The developer can add comments to the
151 phrases.
152
153 Translation files consist of all the user-visible text and \key Ctrl key
154 shortcuts in an application and translations of that text.
155
156 To create translation files:
157
158 \list 1
159
160 \li Run \c lupdate to generate the first set of translation source (TS)
161 files with all the user-visible text but no translations.
162
163 \li Give the TS files to translators who add translations using \QL.
164 \QL indicates changed and deleted source text.
165
166 \li Run \c lupdate to incorporate any new text added to the application.
167 \c lupdate synchronizes the user-visible text from the application
168 with the translations. Existing translations in the TS file are
169 preserved.
170
171 \li Run \c lrelease to read the TS files and produce the QM files used
172 by the application at runtime.
173
174 \endlist
175
176 For \c lupdate to work successfully, it must know which translation files to
177 produce. Specify the files in the application's Qt project file.
178
179 When building with CMake, you use \l{CMake Commands in Qt6 LinguistTools}
180 {CMake commands} to add targets that create or update TS files and transform
181 them into QM files. The translation files are generated when you build the
182 targets.
183*/
184
185/*!
186 \page linguist-lupdate.html
187 \target lupdate
188
189 \previouspage Release managers
190 \nextpage Using lrelease
191
192 \title Using lupdate
193
194 The \c lupdate command line tool finds translatable strings in C++ source,
195 C++ header, Java, Python, QML, and UI files and generates or updates TS
196 files.
197
198 When building with qmake, specify the files to process at the command line
199 or in a .pro file.
200
201 When building with CMake, use \l{CMake Commands in Qt6 LinguistTools}
202 {CMake commands} to add targets that create or update TS files and transform
203 them into QM files. The \c lupdate tool is run with the \l {lupdate options}
204 {options} you pass to the commands when you build the target.
205
206 For more information about specifying translations in project files, see
207 \l{Localizing Applications}.
208
209 \section1 lupdate syntax
210
211 \badcode
212 lupdate [options] [project-file]...
213 lupdate [options] [source-file|path|@lst-file]... -ts ts-files|@lst-file
214 \endcode
215
216 Where:
217
218 \list
219 \li \c options means one or several \l {lupdate options}.
220 \li \c project-file is the project configuration file.
221 \li \c source-file is a file that contains translatable strings.
222 \li \c path is the path to a folder that contains translation
223 source files.
224 \li \c @lst-file reads additional file names (one per line) or
225 includepaths (one per line and prefixed with \c -I) from \e lst-file.
226 \li \c ts-files are the TS files to generate or update.
227 \endlist
228
229 To view the latest help, enter:
230
231 \badcode
232 lupdate -help
233 \endcode
234
235 \section2 lupdate options
236
237 \table
238 \header
239 \li Option
240 \li Action
241 \row
242 \li \c {-help}
243 \li Display up-to-date help information and exit.
244 \row
245 \li \c {-no-obsolete}
246 \li Drop all obsolete and vanished strings.
247 \row
248 \li \c {-extensions <ext>[,<ext>]...}
249 \li Process files with the given extensions, only. Use commas to
250 separate extensions in the list. Do not use whitespace. The default
251 value is:
252 \c {java,jui,ui,c,c++,cc,cpp,cxx,ch,h,h++,hh,hpp,hxx,js,qs,qml,qrc}.
253 \row
254 \li \c {-pluralonly}
255 \li Only include plural form messages.
256 \row
257 \li \c {-silent}
258 \li Do not explain what is being done.
259 \row
260 \li \c {-no-sort}
261 \li Do not sort contexts in TS files.
262 \row
263 \li \c {-sort-messages}
264 \li Sort messages in a context alphabetically in TS files.
265 \row
266 \li \c {-no-recursive}
267 \li Do not recursively scan directories.
268 \row
269 \li \c {-recursive}
270 \li Recursively scan directories (default).
271 \row
272 \li \c {-warnings-are-errors}
273 \li Treat warnings as errors.
274 \row
275 \li \c {-I <includepath> or -I<includepath>}
276 \li Look for include files in this additional location. You can specify
277 multiple paths.
278 \row
279 \li \c {-locations {absolute|relative|none}}
280 \li Specify or override the way to save source code references in TS
281 files.
282 \list
283 \li \c absolute means that the source file path is relative to
284 the target file, but the line number is absolute.
285 \li \c relative means that the source file path is relative to
286 the target file. The line number is relative to other
287 entries in the same source file.
288 \li \c none stores no information about source location.
289 \endlist
290 If you do not specify the location, \c lupdate determines it from
291 existing TS files. The default value for new files is \c absolute.
292 \row
293 \li \c {-no-ui-lines}
294 \li Do not record line numbers in references to UI files.
295 \row
296 \li \c {-disable-heuristic {sametext|similartext}}
297 \li Disable the named merge heuristic. Can be specified multiple times.
298 \row
299 \li \c {-project <filename>}
300 \li Name of a file containing the project's description in JSON format.
301 You can use the \c lprodump tool to generate the file from a .pro
302 file.
303 \row
304 \li \c {-pro <filename>}
305 \li Name of a .pro file. Useful for files with the .pro file syntax but
306 some other file suffix. Projects are recursed into and merged.
307 This option is deprecated. Use the \c lupdate-pro tool instead.
308 \row
309 \li \c {-pro-out <directory>}
310 \li Virtual output directory for processing subsequent .pro files.
311 \row
312 \li \c {-pro-debug}
313 \li Trace processing .pro files. Specify twice for more verbosity.
314 \row
315 \li \c {-source-language <language>[_<region>]}
316 \li Specify the language of the source strings for new files.
317 Defaults to POSIX if not specified.
318 \row
319 \li \c {-target-language <language>[_<region>]}
320 \li Specify the language of the translations for new files.
321 If you do not specify the language, \c lupdate determines it from
322 the file name.
323 \row
324 \li \c {-tr-function-alias <function>{+=,=}<alias>[,<function>{+=,=}<alias>]...}
325 \li With \c {+=}, recognize \c <alias> as an alternative spelling of
326 \c <function>.
327 With \c {=,} recognize \c <alias> as the only spelling of
328 \c <function>.
329
330 Available \c <function> values (with their currently defined aliases)
331 are:
332 \list
333 \li \c {Q_DECLARE_TR_FUNCTIONS} (\c {=Q_DECLARE_TR_FUNCTIONS})
334 \li \c {QT_TR_N_NOOP} (\c {=QT_TR_N_NOOP})
335 \li \c {QT_TRID_N_NOOP} (\c {=QT_TRID_N_NOOP})
336 \li \c {QT_TRANSLATE_N_NOOP} (\c {=QT_TRANSLATE_N_NOOP})
337 \li \c {QT_TRANSLATE_N_NOOP3} (\c {=QT_TRANSLATE_N_NOOP3})
338 \li \c {QT_TR_NOOP} (\c {=QT_TR_NOOP})
339 \li \c {QT_TRID_NOOP} (\c {=QT_TRID_NOOP})
340 \li \c {QT_TRANSLATE_NOOP} (\c {=QT_TRANSLATE_NOOP})
341 \li \c {QT_TRANSLATE_NOOP3} (\c {=QT_TRANSLATE_NOOP3})
342 \li \c {QT_TR_NOOP_UTF8} (\c {=QT_TR_NOOP_UTF8})
343 \li \c {QT_TRANSLATE_NOOP_UTF8} (\c {=QT_TRANSLATE_NOOP_UTF8})
344 \li \c {QT_TRANSLATE_NOOP3_UTF8} (\c {=QT_TRANSLATE_NOOP3_UTF8})
345 \li \c {findMessage} (\c {=findMessage})
346 \li \c {qtTrId} (\c {=qtTrId})
347 \li \c {tr} (\c {=tr})
348 \li \c {trUtf8} (\c {=trUtf8})
349 \li \c {translate} (\c {=translate})
350 \li \c {qsTr} (\c {=qsTr})
351 \li \c {qsTrId} (\c {=qsTrId})
352 \li \c {qsTranslate} (\c {=qsTranslate})
353 \endlist
354 \row
355 \li \c {-ts <ts-file>...}
356 \li Specify the output files. This overrides \c TRANSLATIONS.
357 \row
358 \li \c {-version}
359 \li Display the version of \c lupdate and exit.
360 \endtable
361
362 \section1 Examples
363
364 \section2 Using lupdate with CMake
365
366 When building with CMake, use \l{CMake Commands in Qt6 LinguistTools}
367 {CMake commands} to add translations on targets to the CMakeLists.txt
368 file, and then build the targets.
369
370 Select one of the following options:
371
372 \list
373 \li Use \l qt_add_translations on a target, such as \e app.
374 This calls \l qt_add_lupdate and \l qt_add_lrelease.
375 \li Use \c qt_add_lupdate on a target.
376 \endlist
377
378 Build a target (for example, \c app_lupdate) to update the .ts
379 files for it. To update the .ts files for all targets, build the
380 target \c {update_translations}.
381
382 \section2 Using lupdate with qmake
383
384 To generate a translation file for a single QML file:
385
386 \badcode
387 lupdate main.qml -ts main_en.ts
388 \endcode
389
390 To make a translation file for another language, for example French,
391 copy main_en.ts to main_fr.ts, and translate the strings in the
392 French TS file.
393
394 \c lupdate processes QML files that are listed in the \c .qrc file:
395
396 \badcode
397 RESOURCES += qml.qrc
398 \endcode
399
400 To have all QML files processed by \c lupdate:
401
402 \badcode
403 lupdate application.qrc -ts myapp_en.ts
404 \endcode
405
406 To process all QML files in the current working directory (or its subfolders)
407 without using a \c .qrc file:
408
409 \badcode
410 lupdate . -extensions qml -ts myapp_en.ts
411 \endcode
412
413 To check for translatable strings in both QML and C++ source files:
414
415 \badcode
416 lupdate qml.qrc filevalidator.cpp -ts myapp_en.ts
417 \endcode
418
419 To generate .ts files that will be used for English and French without
420 specifying the languages in the project file:
421
422 \badcode
423 lupdate qml.qrc filevalidator.cpp -ts myapp_en.ts myapp_fr.ts
424 \endcode
425
426 Give the TS files to the translator who uses \QL to read the files and
427 insert the translations.
428
429 \section1 XLIFF format files
430
431 The TS file format is a simple human-readable XML format that you
432 can use with version control systems. In addition, \c lupdate can
433 process Localization Interchange File Format (XLIFF) files (\c .xlf).
434
435 \note Only XLIFF versions 1.1 and 1.2 are currently supported.
436
437 You can open and edit XLIFF files in \QL.
438*/
439
440/*!
441 \page linguist-lrelease.html
442 \target lrelease
443
444 \previouspage Using lupdate
445 \nextpage Using lconvert
446
447 \title Using lrelease
448
449 The \c lrelease command line tool produces QM files out of TS files. The
450 QM file format is a compact binary format that the localized application
451 uses. It provides extremely fast lookup for translations.
452
453 When building with qmake, specify the files to process at the command line
454 or in a .pro file.
455
456 When building with CMake, use \l{CMake Commands in Qt6 LinguistTools}
457 {CMake commands} to add targets that create or update TS files and
458 transform them into QM files. The \c lrelease tool is run with the
459 \l {lrelease options}{options} you pass to the commands when you build
460 the target.
461
462 Run \c lrelease whenever you want to release the application, from the
463 initial test version through to the final release version. The application
464 does not need QM files to run, but if they are available, the application
465 detects them and uses them automatically.
466
467 \note The \c lrelease tool only incorporates translations that you
468 mark as \e finished. Otherwise, it uses the original text instead.
469
470 \section1 lrelease syntax
471
472 \badcode
473 lrelease [options] -project project-file
474 lrelease [options] ts-files [-qm qm-file]
475 \endcode
476
477 Where:
478
479 \list
480 \li \c options means one or several \l {lrelease options}.
481 \li \c project-file is the project configuration file.
482 \li \c ts-files are the TS files to use as input for the QM files.
483 \li \c qm-file is the name of the QM file to generate.
484 \endlist
485
486 \note Passing .pro files to \c lrelease is deprecated. Use the
487 \c lrelease-pro tool or the \c lrelease.prf feature when using qmake.
488
489 To view the latest help, enter:
490
491 \badcode
492 lrelease -help
493 \endcode
494
495 \section2 lrelease options
496
497 \table
498 \header
499 \li Option
500 \li Action
501 \row
502 \li \c {-help}
503 \li Display up-to-date help information and exit.
504 \row
505 \li \c {-idbased}
506 \li Deprecated. The flag is not required anymore and will be removed
507 in a future version. It was used to enable ID based translation.
508 \row
509 \li \c {-compress}
510 \li Compress the QM files.
511 \row
512 \li \c {-nounfinished}
513 \li Do not include unfinished translations.
514 \row
515 \li \c {-fail-on-unfinished}
516 \li Generate an error if unfinished translations are found
517 \row
518 \li \c {-removeidentical}
519 \li If the translated text is the same as the source text, exclude the
520 message.
521 \row
522 \li \c {-markuntranslated <prefix>}
523 \li If a message has no real translation, use the source text
524 prefixed with the given string instead.
525 \row
526 \li \c {-project <filename>}
527 \li Name of a file containing the project's description in JSON format.
528 You can use the \c lprodump tool to generate the file from a .pro
529 file.
530 \row
531 \li \c {-silent}
532 \li Do not explain what is being done.
533 \row
534 \li \c {-verbose}
535 \li Explain what is being done (default).
536 \row
537 \li \c {-version}
538 \li Display the version of \c lrelease and exit.
539 \endtable
540
541 \section1 Examples
542
543 \section2 Using lrelease with CMake
544
545 When building with CMake, use \l{CMake Commands in Qt6 LinguistTools}
546 {CMake commands} to add translations on targets to the CMakeLists.txt
547 file, and then build the targets.
548
549 Select one of the following options:
550
551 \list
552 \li Use \l qt_add_translations on a target, such as \e app.
553 This calls \l qt_add_lupdate and \l qt_add_lrelease.
554 \li Use \c qt_add_lrelease on a target.
555 \endlist
556
557 Build a target (for example, \c app_lrelease) to update the .qm
558 files for it. To update the .qm files for all targets, build the
559 target \c {release_translations}.
560
561 \section2 Using lrelease with qmake
562
563 To run \c lrelease without specifying a project file:
564
565 \badcode
566 lrelease.exe main_en.ts languages\main_fr.ts
567 \endcode
568*/
569
570/*!
571 \page linguist-lconvert.html
572 \target lconvert
573
574 \previouspage Using lrelease
575 \nextpage Using lconvert
576
577 \title Using lconvert
578
579 The \c lconvert command line tool filters and converts translation data
580 files.
581
582 It supports the following file formats:
583 \list
584 \li \c pot - GNU Gettext localization template files
585 \li \c qph - Qt Linguist Phrase Book
586 \li \c ts - Qt translation sources
587 \li \c po - GNU Gettext localization files
588 \li \c qm - Compiled Qt translations
589 \li \c xlf - XLIFF localization files
590 \endlist
591
592 \section1 lconvert syntax
593
594 \badcode
595 lconvert [options] <infile> [<infile>...]
596 \endcode
597
598 Where:
599
600 \list
601 \li \c options means one or several \l {lconvert options}.
602 \li \c infile is an input file. You can specify multiple input files.
603 \endlist
604
605 If you specify multiple input files, they are merged with translations from
606 later files taking precedence.
607
608 To view the latest \c lconvert help, enter:
609
610 \badcode
611 lconvert -help
612 \endcode
613
614 \section2 lconvert options
615
616 \table
617 \header
618 \li Option
619 \li Action
620 \row
621 \li \c -h \br \c -help
622 \li Display up-to-date help information and exit.
623 \row
624 \li \c {-i <infile>} \br \c {-input-file <infile>}
625 \li Specify an input file. Use this option if \c{<infile>} starts with a dash.
626 Use this option several times to merge inputs.
627 May be \c {-} (standard input) for use in a pipe.
628 \row
629 \li \c {-o <outfile>} \br \c {-output-file <outfile>}
630 \li Specify an output file. Default is \c {-} (standard output).
631 \row
632 \li \c {-if <informat>} \br \c {-input-format <format>}
633 \li Specify input format for subsequent input files.
634 The format is auto-detected from the file name and defaults to \c ts.
635 \row
636 \li \c {-of <outformat>} \br \c {-output-format <outformat>}
637 \li Specify output format. See \c -if.
638 \row
639 \li \c {-drop-tags <regexp>}
640 \li Drop named extra tags when writing \c TS or \c XLIFF files.
641 You can specify this option repeatedly.
642 \row
643 \li \c {-drop-translations}
644 \li Drop existing translations and reset the status to \c unfinished.
645 That implies \c {--no-obsolete}.
646 \row
647 \li \c {-source-language <language>[_<region>]}
648 \li Specify/override the language of the source strings. Defaults to
649 POSIX if not specified and the file does not name it yet.
650 \row
651 \li \c {-target-language <language>[_<region>]}
652 \li Specify or override the language of the translation.
653 By default, the target language is read from the file content or
654 guessed from the file name.
655 \row
656 \li \c {-no-obsolete}
657 \li Drop obsolete messages.
658 \row
659 \li \c {-no-finished}
660 \li Drop finished messages.
661 \row
662 \li \c {-no-untranslated}
663 \li Drop untranslated messages.
664 \row
665 \li \c {-sort-contexts}
666 \li Sort contexts in the output \c TS file alphabetically.
667 \row
668 \li \c {-sort-messages}
669 \li Sort messages in a context alphabetically in \c TS files.
670 \row
671 \li \c {-locations {absolute|relative|none}}
672 \li Override how source code references are saved in \c TS files.
673 Default is \c absolute.
674 \row
675 \li \c {-no-ui-lines}
676 \li Drop line numbers from references to \c UI files.
677 \row
678 \li \c {-pluralonly}
679 \li Drop non-plural form messages.
680 \row
681 \li \c {-verbose}
682 \li Explain what is being done.
683 \endtable
684
685 \section1 Examples
686
687 \section2 Convert TS file to XLIFF
688
689 To convert a single TS file to XLIFF, run the following command in the
690 terminal:
691
692 \badcode
693 lconvert -o myapp_de.xlf myapp_de.ts
694 \endcode
695
696 \section2 Merge multiple QM files
697
698 The following command merges multiple QM files into \c {full_de.qm}:
699
700 \badcode
701 lconvert -o full_de.qm qtbase_de.qm myapp_de.qm mylib_de.qm
702 \endcode
703
704 \section2 Using lconvert with CMake
705
706 To call \c lconvert when configuring or building your CMake project, load
707 the \c Qt6LinguistTools package and use \c
708 {$<TARGET_FILE_NAME:Qt6::lconvert>} for locating the \c lconvert executable.
709
710 The following example adds a custom target \c xlf_de that converts a single
711 TS file to XLIFF.
712
713 \badcode
714 find_package(Qt6 REQUIRED COMPONENTS LinguistTools)
715
716 add_custom_command(
717 OUTPUT myapp_de.xlf
718 COMMAND $<TARGET_FILE:Qt6::lconvert> -o myapp_de.xlf myapp_de.ts
719 DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/myapp_de.ts"
720 VERBATIM
721 )
722
723 add_custom_target(xlf_de
724 DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/myapp_de.xlf"
725 )
726 \endcode
727*/
728
729/*!
730\page linguist-lcheck.html
731\target lcheck
732\previouspage Using lconvert
733\nextpage Translators
734
735\title Using lcheck
736
737The \c lcheck command line tool validates Qt \c {TS} translation files and
738produces a human-readable report. It is part of the Qt Linguist toolchain
739and is intended for batch or CI usage to catch common localization issues
740early. By default, \c lcheck runs a set of checks and returns a non-zero
741exit code if at least one enabled check fails.
742
743The default checks are:
744
745\list
746 \li \b Accelerator check — Verifies that the number of ampersands
747 (mnemonics) in source and translation match.
748 \li \b Surrounding whitespace check — Verifies that leading and trailing
749 whitespace of source and translation match.
750 \li \b Ending punctuation check — Verifies that source and translation
751 end with the same punctuation.
752 \li \b Place marker check — Verifies consistent usage of \c {%1}, \c {%2},
753 and so on, between source and translation.
754\endlist
755
756Each check can be disabled individually using command line options.
757
758\section1 lcheck syntax
759
760\badcode
761lcheck [options] -o report-output-file ts-file
762lcheck [options] ts-file
763\endcode
764
765Where:
766
767\list
768 \li \c options means one or several \l {lcheck options}.
769 \li \c ts-file is the \c {TS} file to validate.
770 \li \c report-output-file is the path of the file to write the report to.
771 If omitted, the report is written to the standard error stream.
772\endlist
773
774To view the latest help, enter:
775
776\badcode
777lcheck -help
778\endcode
779
780\section2 lcheck options
781
782\table
783\header
784 \li Option
785 \li Action
786\row
787 \li \c {-help}
788 \li Display up-to-date help information and exit.
789\row
790 \li \c {-no-accelerator}
791 \li Disable the accelerator (ampersand) consistency check.
792\row
793 \li \c {-no-punctuation}
794 \li Disable the ending punctuation consistency check.
795\row
796 \li \c {-no-place-marker}
797 \li Disable the check that ensures \c {%1}, \c {%2}, … are used
798 consistently between source and translation.
799\row
800 \li \c {-no-whitespaces}
801 \li Disable the surrounding whitespace consistency check.
802\row
803 \li \c {-check-finished}
804 \li Also check messages marked as \e finished. By default, finished
805 translations are not checked.
806\row
807 \li \c {-o <outfile>}
808 \li Write the validation report to \c <outfile>. If not specified, the
809 report is written to standard error.
810\row
811 \li \c {-version}
812 \li Display the version of \c lcheck and exit.
813\endtable
814
815\note The process exit status is non-zero if any enabled check fails. This
816makes \c lcheck suitable for use in CI pipelines.
817
818\section1 Examples
819
820\section2 Write a report to a file
821
822\badcode
823lcheck -o lcheck_report.txt translations/myapp_de.ts
824\endcode
825
826\section2 Disable selected checks
827
828The following command runs all checks except accelerator and punctuation:
829
830\badcode
831lcheck -no-accelerator -no-punctuation translations/myapp_de.ts
832\endcode
833
834\section2 Check finished translations as well
835
836\badcode
837lcheck -check-finished translations/myapp_de.ts
838\endcode
839
840\section2 Use lcheck in a CI step
841
842\badcode
843lcheck translations/myapp_de.ts && echo "Translations OK" || echo "Issues found"
844\endcode
845
846\section2 Using lcheck with CMake
847
848To call \c lcheck when configuring or building your CMake project, load
849the \c Qt6LinguistTools package and use \c {$<TARGET_FILE:Qt6::lcheck>}
850to locate the \c lcheck executable.
851
852The following example adds a custom target \c check_translations that runs
853\c lcheck over a TS file and writes a report next to the build artifacts.
854
855\badcode
856find_package(Qt6 REQUIRED COMPONENTS LinguistTools)
857
858add_custom_command(
859 OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/lcheck_report.txt"
860 COMMAND $<TARGET_FILE:Qt6::lcheck>
861 -o "${CMAKE_CURRENT_BINARY_DIR}/lcheck_report.txt"
862 "${CMAKE_CURRENT_SOURCE_DIR}/translations/myapp_de.ts"
863 DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/translations/myapp_de.ts"
864 VERBATIM
865)
866
867add_custom_target(check_translations
868 DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/lcheck_report.txt"
869)
870\endcode
871
872\section2 Using lcheck with qmake
873
874You can run \c lcheck directly on a TS file without specifying a project file:
875
876\badcode
877lcheck translations/myapp_de.ts
878\endcode
879*/
880
881/*!
882 \page linguist-translators.html
883
884 \previouspage Using lcheck
885 \nextpage Qt Linguist user interface
886
887 \title Translators
888
889 \image front-ui.png
890
891 \QL is a tool for translating strings in Qt applications. Once you have
892 installed Qt, you can start \QL in the same way as any other application on
893 the development host.
894
895 \note You can obtain an installer for \QL only (without the entire Qt SDK)
896 from \l {https://download.qt.io/linguist_releases/}. The installer is
897 available for Windows, and works with Qt 6.
898
899 To address issues that arise from the subtleties and complexities of
900 human language, translators and developers may need to:
901
902 \list
903 \li Translate a single phrase into several different forms depending on
904 context. For example, \e open in English might become \e{\ouml}\e{ffnen},
905 \e {open file}, or \e aufbauen, \e {open internet connection}, in German.
906
907 \li Change the mnemonic characters in keyboard shortcuts without introducing
908 conflicts. For example, \c \&Quit in English becomes \e Avslutt in
909 Norwegian, which does not contain the letter \e Q. You cannot use a
910 letter that is already in use unless you change several shortcuts.
911
912 \li Rephrase strings that contain variables. For example, you might need to
913 place the variables in a different order when you translate the string
914 \e {The 25 files selected will take 63 seconds to process}, where the
915 two numbers are inserted programmatically at runtime.
916 \endlist
917
918 For more information about how to use \QL to translate applications, see:
919
920 \list
921 \li \l {Qt Linguist user interface}
922 \li \l {Translating strings}
923 \li \l {Selecting context or label to translate}
924 \li \l {Selecting strings to translate}
925 \li \l {Viewing strings in context}
926 \li \l {Reusing translations}
927 \li \l {Validating translations}
928 \li \l {Translating multiple languages simultaneously}
929 \li \l {AI translation}
930 \endlist
931*/
932
933/*!
934 \page linguist-ui.html
935
936 \previouspage Translators
937 \nextpage Translating strings
938
939 \title Qt Linguist user interface
940
941 The \QL main window contains a menu bar and the following views:
942
943 \list
944
945 \li \uicontrol Context/Label (\key F6) lists translation contexts or labels.
946
947 \li \uicontrol Strings (\key F7) lists translatable strings in the
948 selected context.
949
950 \li \uicontrol {Sources and Forms} (\key F9) displays the selected
951 string in the source code.
952
953 \li Translation area displays the selected string and enables you to
954 enter a translation for it.
955
956 \li \uicontrol {Phrases and guesses} (\key F10) lists possible
957 translations for the current string.
958
959 \li \uicontrol Warnings (\key F8) lists translated strings that fail
960 validation tests.
961
962 \endlist
963
964 \image linguist.webp {Qt Linguist UI}
965
966 The translation area (1) is always visible. To show or hide the other views,
967 select \uicontrol View > \uicontrol Views, or use keyboard shortcuts.
968 You can drag the views by their title bars and arrange them around the
969 translation area or even outside the main window.
970*/
971
972/*!
973 \page linguist-translating-strings.html
974
975 \previouspage Qt Linguist user interface
976 \nextpage Selecting context or label to translate
977
978 \title Translating strings
979
980 Open translation source (TS) files in \QL for translation. TS files are
981 human-readable XML files containing source phrases and their translations.
982 TS files are usually created and updated by \c lupdate. If you do not have
983 a TS file, see \l {Creating translation files} to learn how to generate one.
984
985 You can use \QL also to translate files in the international XML
986 Localization Interchange File Format (XLIFF) that are generated by other
987 programs. However, for standard Qt projects, only the TS file format is
988 used. Only XLIFF versions 1.1 and 1.2 are currently supported.
989
990 \QL displays the target language in the translation area, and adapts the
991 number of input fields for plural forms accordingly. When you open several
992 TS files to translate simultaneously, the \uicontrol Translator and
993 \uicontrol {Translator comment} fields are displayed for each language.
994 For more information about setting the location information, see
995 \l{Changing the target locale}.
996
997 If the developer provides a disambiguating comment, you can see it in the
998 \uicontrol {Developer comments} field.
999
1000 To translate strings:
1001 \list 1
1002
1003 \li Select \uicontrol File > \uicontrol Open to load a TS file.
1004
1005 \li Select a context in the \uicontrol Context view to display translatable
1006 strings in the \uicontrol Strings view.
1007
1008 \image linguist-ui.webp {}
1009
1010 \li Select a string to display it in the \uicontrol {Source text} field
1011 in the translation area. The whitespace within the source text is
1012 visualized.
1013
1014 \li Enter the translation of the current string in the \uicontrol Translation
1015 field.
1016
1017 Double-click an existing translation in the
1018 \uicontrol {Phrases and guesses} field to use it as the translation
1019 for the current string. \QL reads the phrases from phrase books and
1020 bases the guesses on existing translations of similar phrases in the
1021 TS file.
1022
1023 \li Optionally, enter a comment for other translators in the
1024 \uicontrol {Translator comment} field.
1025
1026 \li To accept the translation, press \key {Ctrl+Enter}, select
1027 \inlineimage linguist-doneandnext.png
1028 , or click the icon to the left of the selected source string in the
1029 string list.
1030
1031 \li Select \uicontrol File > \uicontrol Save to save your work.
1032
1033 \endlist
1034
1035 Repeat this process until all strings in the string list are marked with
1036 \inlineimage linguist-check-on.png
1037 (\uicontrol {Accepted/Correct}) or
1038 \inlineimage linguist-check-warning.png
1039 (\uicontrol {Accepted/Warnings}). Then select the next context and continue.
1040
1041 To view the number of words and characters in the source text and in the
1042 translated text, select \uicontrol View > \uicontrol Statistics.
1043
1044 Select \uicontrol File > \uicontrol Release to create a QM
1045 file with the same base name as the current translation source file.
1046 The \c lrelease tool performs the same function on \e all of an
1047 application's translation source files.
1048
1049 To print the translation source and the translations, select \uicontrol File >
1050 \uicontrol Print.
1051
1052 To quit \QL, select \uicontrol File > \uicontrol Exit.
1053
1054 \section1 Moving between translatable strings
1055
1056 To move to the next unfinished translation, select
1057 \inlineimage nextunfinished.png
1058 (\uicontrol {Next Unfinished}) or press \key{Ctrl+J}.
1059
1060 To move to the next source text, select \inlineimage next.png
1061 , press \key{Ctrl+Shift+J}, or select \uicontrol Translation >
1062 \uicontrol Next.
1063
1064 \section1 Phrases that require multiple translations depending on context
1065
1066 The same phrase may occur in more than one context without conflict. When
1067 you reach another occurrence of a translated phrase, \QL provides
1068 the previous translation as a possible translation in the
1069 \uicontrol {Phrases and guesses} view.
1070
1071 If a phrase occurs more than once within a particular context, it appears
1072 only once in the \uicontrol Context view, and the translation is applied
1073 to every occurrence within the context. If the same phrase means different
1074 things within the same context, the developer must provide a comment for
1075 each occurrence of the phrase. The duplicate phrases appear in the
1076 \uicontrol Context view. The developer's comments appear in the translation
1077 area on a light blue background.
1078
1079 \section1 Changing keyboard shortcuts
1080
1081 A keyboard shortcut is a key combination that performs an action.
1082
1083 \section2 Alt key shortcuts
1084
1085 In menu item and button text, a \e mnemonic character (marked by underlining)
1086 indicates that pressing \key Alt or \key Ctrl with the underlined character
1087 performs the same action as clicking the menu item or pressing the button.
1088
1089 For example, applications often use \e F as the mnemonic character in the
1090 \uicontrol {File} menu, so you can either click the menu item or press
1091 \key {Alt+F} to open the menu. The mnemonic character in the translatable
1092 string is prefixed with an ampersand: \c {\&File}. The translation for the
1093 string should also have an ampersand in it, preferably in front of the same
1094 character.
1095
1096 You can determine the meaning of an \key Alt key shortcut from the phrase
1097 that contains the ampersand. You can use another mnemonic character if the
1098 translated phrase does not contain the current one or if it is used in
1099 the translation of some other shortcut in the context. Some key shortcuts,
1100 usually those on the menu bar, may apply in other contexts.
1101
1102 \section2 Ctrl key shortcuts
1103
1104 \key Ctrl key shortcuts can exist independently of any visual control.
1105 Typically, they invoke actions in menus that would require multiple
1106 keystrokes or mouse clicks or actions that do not appear in any menu
1107 or on any button. For example, the \uicontrol {File} menu might contain a
1108 \uicontrol {\underline{N}ew Ctrl+N} item that you can invoke by pressing
1109 \key {Ctrl+N} even when the \uicontrol {File} menu is closed.
1110
1111 Each \key Ctrl key shortcut appears in the \uicontrol Strings view
1112 as a separate string. For example, \key{Ctrl+Enter}. Since
1113 the string does not have a context to give it meaning, such as
1114 the context of the phrase in which an \key Alt key shortcut appears,
1115 you must rely on the developer to include a \l{QObject::tr()}
1116 {disambiguation comment} to explain the action the \key Ctrl key
1117 shortcut performs. The comment appears under \uicontrol {Developer comments}
1118 in the translation area below the \uicontrol {Source text} field.
1119
1120 Ideally, you can copy translations for \key Ctrl key shortcuts by
1121 selecting \uicontrol Translation > \uicontrol {Copy from source text}.
1122 However, if the character does not make sense in the target language,
1123 change it. Whichever character (alpha or digit) you choose, use the form
1124 \key {Ctrl+} followed by the upper case character. Qt automatically displays
1125 the correct name at runtime. As with \key Alt key shortcuts, if you change
1126 the character, make sure that it does not conflict with any other
1127 \key Ctrl key shortcut.
1128
1129 \note Do not translate the \key Alt, \key Ctrl or \key Shift parts of
1130 the shortcuts, as Qt recognizes them and automatically translates them
1131 for supported languages.
1132
1133 \section1 Handling numbered arguments and plural forms
1134
1135 A numbered argument is a placeholder that will be replaced with text at
1136 runtime. It appears in a source string as a percent sign followed by
1137 a digit. For example, in the \c{After processing file %1, file %2
1138 is next in line} string, \c{%1} and \c{%2} are numbered arguments that
1139 are replaced with the first and second file names at runtime. The
1140 same numbered arguments must appear in the translation, but not
1141 necessarily in the same order. A German translation of the string
1142 might reverse the phrases, for example \c{Datei %2 wird bearbeitet, wenn
1143 Datei %1 fertig ist}. Both numbered arguments appear in the
1144 translation, but in the reverse order. A numbered argument is always
1145 replaced by the same text in the translations, regardless of the position
1146 in the argument sequence in the source string.
1147
1148 The use of numbered arguments is often accompanied by the use of
1149 plural forms in the source text. In many languages, the form of the
1150 text will depend on the value shown, and more than one translation
1151 is required. If the developers have marked up the source text in
1152 correct way, fields for each of the possible plural forms will be
1153 available in the translation area. For more information, see
1154 \l{Writing Source Code for Translation}.
1155
1156 \section1 Handling numeric character references (NCR) in translations
1157
1158 Select \uicontrol {NCR mode} to toggle the representation of
1159 numeric character references in both the source text and the translation
1160 fields. When selected, special characters in the text are displayed as their
1161 corresponding NCRs (for examlple, &#160; for a non-breaking space). Otherwise, the
1162 characters appear in their standard visual form. This feature is useful
1163 for instance to maintain the same special characters (such as
1164 emojis, special spaces) in both the source text and its translations.
1165
1166 \section1 Changing the target locale
1167
1168 You can set the locale information explicitly in \uicontrol Edit >
1169 \uicontrol {Translation File Settings}. If the target language and country
1170 are not explicitly set when you open a translation source file, \QL
1171 attempts to deduct them from the translation source file name. This
1172 requires that the translation files adhere to the following file name
1173 convention:
1174 \c appname_language[_country].ts, where:
1175
1176 \list
1177 \li \c language is an ISO 639 language code in lowercase.
1178 \li \c country is an ISO 3166 two-letter country code in uppercase.
1179 \endlist
1180
1181 If this attempt to resolve the target language and country fails, the
1182 \uicontrol {Translation File Settings} window opens.
1183
1184 For example, \c app_de.ts sets the
1185 target language to German, and \c app_de_CH.ts sets the target language to
1186 German and the target country to Switzerland. This also helps loading
1187 translations for the current locale automatically. For more information, see
1188 \l{Enable Translation}.
1189
1190 \image linguist-translationfilesettings.png
1191*/
1192
1193/*!
1194 \page linguist-selecting-context.html
1195
1196 \previouspage Translating strings
1197 \nextpage Selecting strings to translate
1198
1199 \title Selecting context or label to translate
1200
1201 The \uicontrol Context/Label view lists the contexts (\uicontrol {Text based}) or
1202 labels (\uicontrol {ID based}) in which strings to be translated
1203 appear. The text-based translations are grouped into contexts, while ID-based
1204 translations are grouped into labels (see \l{Grouping ID-Based Translations}).
1205 The \uicontrol Context/Label lists the \e groups (that is, context or labels)
1206 based on the selected tab:
1207 \list
1208 \li Upon switching to the \uicontrol{Text-Based} tab,
1209 \uicontrol Context lists the context names in
1210 alphabetical order. Each context is the name of a QML type or a subclass of
1211 QObject.
1212 \li Upon switching to the \uicontrol{ID-Based} tab,
1213 \uicontrol Label lists the label names in
1214 alphabetical order. More info on labels can be found in \l{Grouping ID-Based Translations}.
1215 \endlist
1216
1217 \image linguist-context-view.webp {Context/Label view}
1218
1219 The following icons indicate the current translation state for each group:
1220
1221 \table
1222 \header
1223 \li State
1224 \li Icon
1225 \li Description
1226
1227 \row
1228 \li Accepted/Correct
1229 \li \inlineimage linguist-check-on.png
1230 \li All strings in the group have been translated, and all the
1231 translations passed the \l{Validating Translations}{validation tests}.
1232
1233 \row
1234 \li Accepted/Warnings
1235 \li \inlineimage linguist-check-warning.png
1236 \li All strings in the group have been translated or marked as translated,
1237 but at least one translation failed the validation tests.
1238 In the \uicontrol Strings view, you can see which string failed the test.
1239
1240 \row
1241 \li Not Accepted
1242 \li \inlineimage linguist-check-off.png
1243 \li At least one string in the group has not been translated or is not
1244 marked as translated.
1245
1246 \row
1247 \li Obsolete
1248 \li \inlineimage linguist-check-obsolete.png
1249 \li None of the translated strings appears in the group any more. This
1250 usually means the context or label no longer exists in the application.
1251 \endtable
1252
1253 The \uicontrol Items column displays the total number of translatable strings in
1254 the group and the number of translated strings, separated by a slash (/).
1255 If the numbers are equal, all the translatable strings in the group have
1256 translations.
1257*/
1258
1259/*!
1260 \page linguist-selecting-strings.html
1261
1262 \previouspage Selecting context or label to translate
1263 \nextpage Viewing strings in context
1264
1265 \title Selecting strings to translate
1266
1267 The \uicontrol Strings view lists all the translatable strings in the
1268 current group (that is, context or label) and their translation acceptance
1269 state. Select a string to view and edit it in the translation area.
1270
1271 \image linguist-strings-view.webp {Strings view}
1272
1273 Click the icon in front of a string to change its translation acceptance
1274 state. A tick mark, green or yellow, means the string has an accepted
1275 translation. A question mark means either that the translation does not
1276 exist or you have not accepted it.
1277
1278 The following icons indicate the current translation state for each string:
1279
1280 \target String Translation States
1281
1282 \table
1283 \header
1284 \li State
1285 \li Icon
1286 \li Description
1287
1288 \row
1289 \li Accepted/Correct
1290 \li \inlineimage linguist-check-on.png
1291 \li The source string has a translation (possibly empty). You accepted
1292 the translation, and it passes all the \l{Validating Translations}
1293 {validation tests}. Click the icon to revoke acceptance of the
1294 translation. The state becomes \uicontrol {Not Accepted} if the string
1295 has a translation or \uicontrol {No Translation} if the translation is
1296 empty. If \c{lupdate} changes the contents of a string, its acceptance
1297 state becomes \uicontrol {Not Accepted}.
1298
1299 \row
1300 \li Accepted/Warnings
1301 \li \inlineimage linguist-check-warning.png
1302 \li You accepted the translation, but it does not pass all the validation
1303 tests. The \uicontrol Warnings view shows where it failed. If you click
1304 the icon to revoke acceptance of the translation, the state becomes
1305 \uicontrol {Validation Failures}.
1306
1307 \row
1308 \li Not Accepted
1309 \li \inlineimage linguist-check-off.png
1310 \li The string has a translation that passes all the validation tests, but
1311 you have not yet accepted the translation. Click the icon or press
1312 \key{Ctrl+Enter} to accept the translation. The state becomes
1313 \uicontrol {Accepted/Correct}.
1314
1315 \row
1316 \li No Translation
1317 \li \inlineimage linguist-check-empty.png
1318 \li The string does not have a translation. If you click the icon to accept
1319 the empty translation, the state becomes \uicontrol {Accepted/Correct}.
1320
1321 \row
1322 \li Validation Failures
1323 \li \inlineimage linguist-danger.png
1324 \li The string has a translation, but the translation does not pass all the
1325 validation tests. The \uicontrol Warnings view shows the validation test
1326 failures. Click on the icon or press \key{Ctrl+Enter} to
1327 accept the translation even with validation failures. The state becomes
1328 \uicontrol {Accepted/Warnings}. Usually, you should fix the causes of the
1329 validation failures. The state will automatically become
1330 \uicontrol {Not Accepted} when you fix all failures.
1331
1332 \row
1333 \li Obsolete
1334 \li \inlineimage linguist-check-obsolete.png
1335 \li The string is obsolete. It is no longer used in the context.
1336 See \l{Using lupdate} for instructions on how to remove obsolete
1337 messages from the file.
1338
1339 \endtable
1340*/
1341
1342/*!
1343 \page linguist-viewing-strings-in-context.html
1344
1345 \previouspage Selecting strings to translate
1346 \nextpage Reusing translations
1347
1348 \title Viewing strings in context
1349
1350 If \QL can access the source files containing the translatable strings, the
1351 \uicontrol {Sources and Forms} view shows the source context of the current
1352 string in the \uicontrol Strings view. It highlights the source code line
1353 that contains the current string. If \QL cannot find the source file, it
1354 shows the expected absolute file path.
1355
1356 If the source context shows the wrong source line, the translation file might
1357 be out of sync with the source files. For more information about how to sync
1358 the files, see \l{Using lupdate}.
1359
1360 \QD stores UI forms in special UI files (.ui). \QL attempts to show the
1361 translations in the forms.
1362*/
1363
1364/*!
1365 \page linguist-reusing-translations.html
1366
1367 \previouspage Viewing strings in context
1368 \nextpage Validating translations
1369
1370 \title Reusing translations
1371
1372 If the translated text is similar to the source text, select
1373 \uicontrol Translation > \uicontrol {Copy from source text}
1374 (or press \key{Ctrl+B}) to copy the source text into the
1375 translation area.
1376
1377 \e {Phrase books} provide a common set of translations
1378 to help ensure consistency. A phrase book is a set of source phrases, target
1379 (translated) phrases, and optional definitions. Typically, one phrase book
1380 is created per language and family of applications. Phrase books avoid
1381 duplication of effort since they contain translations for a family of
1382 applications.
1383
1384 The \uicontrol {Phrases and guesses} view displays the current string and its
1385 phrase book translations. If the current string is the same as or similar to
1386 a translated string, the view also lists the string and its translation.
1387
1388 To copy a translation from the \uicontrol {Phrases and guesses} view to the
1389 translation area, double-click it or select it and press \key Enter.
1390
1391 \section1 Batch translation
1392
1393 \image linguist-batchtranslation.png
1394
1395 Use the batch translation feature to automatically translate source
1396 texts that are also in a phrase book. To configure which phrase books to use
1397 in what order during the batch translation process, select \uicontrol Edit >
1398 \uicontrol {Batch Translation}. You can include only entries with no
1399 current translation and mark batch translated entries as \uicontrol Accepted.
1400
1401 \section1 Creating and editing phrase books
1402
1403 Phrase book files are human-readable XML files containing standard phrases
1404 and their translations. \QL creates and update the files. You can use them
1405 for any number of projects and applications.
1406
1407 To create a new phrase book, select \uicontrol Phrases > \uicontrol {New Phrase Book}.
1408
1409 \image linguist-phrasebookdialog.png
1410
1411 To open a phrase book, select \uicontrol Phrases > \uicontrol {Open Phrase Book}, and
1412 then select the Qt phrase book file (.qph) to open.
1413
1414 To view and change open phrase books, select \uicontrol Phrases >
1415 \uicontrol {Edit Phrase Book}.
1416
1417 To add a new phrase, select \uicontrol {New Entry} (or press \key {Alt+N}) and
1418 type in a new source phrase, the translation, and an optional definition.
1419 This is useful to distinguish different translations of the same source
1420 phrase.
1421
1422 To add the translation you are working on to the current phrase book, select
1423 \uicontrol Phrases > \uicontrol {Add to Phrase Book} or press \key{Ctrl+T}. If multiple
1424 phrase books are loaded, you have to select one.
1425
1426 If you detect an error in a phrase book entry in the
1427 \uicontrol {Phrases and guesses} view, you can edit by right
1428 clicking it and selecting \uicontrol Edit. After fixing the
1429 error press \key{Enter} to leave the editing mode.
1430
1431 To delete a phrase, select it in the \uicontrol {Source phrase} list, and then
1432 select \uicontrol {Remove Entry}.
1433
1434 To print an open phrase book, select \uicontrol Phrases >
1435 \uicontrol {Print Phrase Book}.
1436*/
1437
1438/*!
1439 \page linguist-validating-translations.html
1440
1441 \previouspage Reusing translations
1442 \nextpage Translating multiple languages simultaneously
1443
1444 \title Validating translations
1445
1446 \QL provides the following validation tests for translations:
1447
1448 \list
1449 \li \e {Accelerator validation} detects translated phrases
1450 that do not have an ampersand when the source phrase does and vice
1451 versa.
1452 \li \e {Punctuation validation} detects differences in the
1453 terminating punctuation between source and translated phrases when
1454 this may be significant. For example, warns if the source phrase
1455 ends with an ellipsis, exclamation mark or question mark, and the
1456 translated phrase does not, and vice versa.
1457 \li \e {Phrases validation} detects source phrases that are
1458 also in the phrase book but whose translation differs from that
1459 in the phrase book.
1460 \li \e {Place marker validation} detects whether the same variables
1461 (like \c %1, \c %2) appear both in the source text and in the
1462 translation.
1463 \endlist
1464
1465 To switch validation tests on or off, select \uicontrol Validation or use the
1466 toolbar buttons.
1467
1468 Not accepted strings that fail validation tests are marked with the
1469 \uicontrol {Validation Failures} icon in the \uicontrol Strings view.
1470 Accepted strings are marked with \uicontrol {Accepted/Warnings}.
1471
1472 If you switch validation off and then switch it on later,
1473 \QL rechecks all phrases and marks any that fail validation.
1474
1475 The \uicontrol Warnings view lists the strings that fail the active
1476 validation tests. The first warning is also shown in the status bar
1477 at the bottom of the main window.
1478
1479 \note Only results of \e{active} validation tests are reported.
1480*/
1481
1482/*!
1483 \page linguist-translating-multiple-languages.html
1484 \target multiple languages
1485
1486 \previouspage Validating translations
1487 \nextpage AI translation
1488
1489 \title Translating multiple languages simultaneously
1490
1491 You can load and edit multiple translation files simultaneously.
1492 The following screen shot displays \e{German} and \e{French} translation
1493 files loaded.
1494
1495 \image linguist-linguist_2.webp {}
1496
1497 The translation area has color-coded text editing areas for both German and
1498 French. The \uicontrol Context/Label view and the \uicontrol Strings view have
1499 color-coded status columns for each language.
1500
1501 The \uicontrol Items column in the \uicontrol Context/Label view combines the values
1502 for both languages. If the number of translatable strings does not match the
1503 number of accepted strings, either or both languages have strings that you
1504 need to translate or accept. The \uicontrol Strings view shows the translation
1505 acceptance state of each string for each language.
1506*/
1507
1508/*!
1509 \page linguist-ai-translation.html
1510 \target ai translation
1511
1512 \previouspage Translating multiple languages simultaneously
1513 \nextpage Developers
1514
1515 \title AI translation
1516
1517 The AI Translation feature lets you automatically generate
1518translations for the open TS file using a local LLM via Ollama.
1519
1520 To use AI Translation you must first install
1521\l{https://github.com/jmorganca/ollama}{Ollama} and pull at least one model, for example:
1522
1523 \list
1524 \li \c{ollama pull gpt-oss:20b}
1525 \li \c{ollama pull 7shi/llama-translate:8b-q4_K_M}
1526 \endlist
1527
1528 Then start the Ollama server if not already started:
1529
1530 \code
1531 ollama serve
1532 \endcode
1533
1534 In Linguist, choose \uicontrol{Translation > AI Translation}
1535to open the AI Translation dialog:
1536
1537 \image linguist-ai-translation-dialog.webp
1538
1539 The dialog provides:
1540
1541 \list
1542 \li \uicontrol {Ollama Server}: the REST endpoint where Ollama listens
1543 (default \c http://127.0.0.1:11434).
1544 \li \uicontrol Model: drop-down of locally installed models.
1545 \li \uicontrol File: the TS file to translate.
1546 \li \uicontrol Filter (optional): limit to strings in a specific group (context or label).
1547 \li \uicontrol Translate button: start the AI translation.
1548 \li \uicontrol {Apply Translations} button: apply the translated items into the TS file.
1549 \endlist
1550
1551During translation, progress messages appear in the status bar and in the \uicontrol {Translation
1552Log}. When complete, you can check out the translated texts on the log. Upon clicking on
1553\uicontrol{Apply Translations}, AI-generated translations are inserted into the TS file.
1554
1555\note We suggest using one of OpenAI’s open-weight models, e.g., \e{gpt-oss:20b} or other
1556 LLMs trained for translation, e.g., \e{7shi/llama-translate:8b-q4_K_M}. Feel free to
1557 try other models to find the best combination of speed, quality, and resource usage.
1558*/
1559
1560/*!
1561 \page linguist-programmers.html
1562 \title Developers
1563
1564 \previouspage AI translation
1565 \nextpage TS File Format
1566
1567 \image front-coding.png
1568
1569 Design your application so that it can be adapted to various languages and
1570 regions without engineering changes.
1571
1572 \list
1573 \li \l{TS file format}
1574 \li \l{Text ID based translations}
1575 \li \l{Meta strings reference}
1576 \li \l{CMake Commands in Qt6 LinguistTools}{CMake commands}
1577 \li \l{Examples}
1578 \endlist
1579
1580 For more information, see also:
1581 \list
1582 \li \l {Internationalization with Qt}
1583 \li \l {Writing Source Code for Translation}
1584 \li \l {Localizing Applications}.
1585 \endlist
1586
1587 You can use Qt Creator wizard templates to create Qt widget-based projects
1588 with translation support. For more information, see
1589 \l {Qt Creator: Creating Projects}.
1590
1591 The following video shows how to internationalize and localize a simple
1592 example application:
1593
1594 \youtube xNIz78IPBu0
1595*/
1596
1597/*!
1598 \page linguist-programmers-examples.html
1599 \title Examples
1600
1601 \nextpage Developers
1602
1603 The following examples illustrate how to prepare Qt applications for
1604 translation:
1605
1606 \list
1607 \li \l{hellotr}{Hello tr()} is a C++ application that demonstrates the
1608 creation of a \l QTranslator object. It also shows the simplest use of
1609 the \c tr() function to mark user-visible source text for
1610 translation.
1611
1612 \li \l{arrowpad}{Arrow Pad} is a C++ application that demonstrates how to
1613 make the application load translations depending on the current locale.
1614 It also shows the use of the two-argument form of \c tr() which provides
1615 additional information to the translator.
1616
1617 \li \l{trollprint}{Troll Print} is a C++ application that demonstrates how
1618 to distinguish identical source text in the same context. It also shows
1619 how minimize the translator's work when an application is upgraded.
1620
1621 \li \l{Qt Quick I18N} demonstrates how to internationalize Qt Quick
1622 applications.
1623 \endlist
1624*/
1625
1626/*!
1627 \page linguist-ts-file-format.html
1628 \title TS file format
1629
1630 \previouspage Developers
1631
1632 \brief TS file format.
1633
1634 The TS file format used by \QL is described by the
1635 \l{http://www.w3.org/2001/XMLSchema}{XSD} presented below,
1636 which we include for your convenience. Be aware that the format
1637 may change in future Qt releases.
1638
1639 \quotefile ../../../shared/ts.xsd
1640
1641*/
1642
1643/*!
1644 \page linguist-id-based-i18n.html
1645 \title Text ID based translations
1646 \ingroup internationalization
1647
1648
1649 \brief Text ID based internationalization provides support for large scale
1650 projects with many target locales and many texts to translate.
1651
1652 The text ID translation mechanism is an \e {industrial strength} system for
1653 internationalization and localization. Each text in the application has a
1654 unique identifier (text ID) that you use in the source code instead of text.
1655 This makes it much easier to manage large numbers of translated texts.
1656
1657 \section1 Internationalizing with text IDs
1658
1659 When using text IDs instead of plain text, the general method of
1660 internationalizing an application is the same but the details are a bit
1661 different:
1662
1663 \list 1
1664
1665 \li The functions and macros for the text-ID-based translation system are
1666 different from the plain-text system. You use the qsTrId() function instead
1667 of qsTr(), the QT_TRID_NOOP() macro instead of QT_TR_NOOP(),
1668 and QT_TRID_N_NOOP() macro instead of QT_TR_N_NOOP()).
1669
1670 \li Use text IDs as user interface strings rather than plain text
1671 strings. For example, \c {qsTrId("id-back-not-front")}
1672
1673 \li You cannot specify a context parameter with a text ID, and therefore
1674 identically spelled words with different meanings need separate
1675 text IDs. For example, \c {qsTrId("id-back-backstep")} differentiates
1676 the back-step \e {Back} from the \c id-back-not-front \e {Back}.
1677
1678 \li Since context names are not allowed for text-ID-based translations,
1679 \QL lists the IDs in a file without context names.
1680
1681 \li The \e {engineering English} text that you see in the user interface for
1682 development builds is indicated with a \c {//%} comment. If you do not
1683 include this, the text ID is shown in the user interface. This is
1684 especially important when you have texts with parameters. The \c {//%}
1685 comment needs to include the parameters indicators in the string. For
1686 example, \c {//% "Number of files: %1"}
1687
1688 \li The \c {//:} comments that provide extra information to the translator
1689 are optional in the plain-text system. However, with the text-ID-based
1690 system, this extra information becomes essential because without it you only
1691 have the text ID and the translator might not be able to make a sensible
1692 translation from that without further context. You can use long descriptive
1693 text IDs and no comments, but comments are often easier to understand.
1694
1695 \endlist
1696
1697 The side-by-side code snippets below show a comparison of text-ID -based and
1698 plain-text-based translations:
1699
1700 \table
1701 \header
1702 \li text-ID-based
1703 \li plain-text-based
1704 \row
1705 \li
1706 \code
1707 Text {
1708 id: backTxt;
1709 //: The back of the object, not the front
1710 //% "Back"
1711 //~ Context Not related to back-stepping
1712 text: qsTrId("id-back-not-front");
1713 }
1714 \endcode
1715
1716 \li
1717 \code
1718 Text {
1719 id: backTxt;
1720 //: The back of the object, not the front
1721 //~ Context Not related to back-stepping
1722 text: qsTr("Back","Not front")
1723 }
1724 \endcode
1725 \endtable
1726
1727 \section1 Localizing with text IDs
1728
1729 Localizing with text IDs follows much the same process as for plain text.
1730
1731 You use the \l{Using lupdate}{lupdate} tool to generate the TS files where
1732 you add the translations. The source values in the translation files will be
1733 text IDs rather than plain text, and therefore you need either descriptive
1734 text IDs or good additional comments, or both to ensure that the translations
1735 are accurate.
1736
1737 The example text-ID-based user interface text from above results in the following
1738 content in the .ts file:
1739
1740 \code
1741 <message id="id-back-not-front">
1742 <source>Back</source>
1743 <extracomment>The back of the object, not the front</extracomment>
1744 <translation type="unfinished"></translation>
1745 <extra-Context>Not related to back-stepping</extra-Context>
1746 </message>
1747 \endcode
1748
1749 If there is no translation available for a given text (which is
1750 generally the case until late in development), the text ID will be shown in
1751 the user interface rather than a proper text. In order to make the application
1752 more usable for testing, you can make \c lrelease use the \e {Engineering English}
1753 source text (from the \c {//%} comments) as the translated text and mark it with
1754 some indicator, such as an exclamation mark (!), so you can see texts that
1755 are not yet translated.
1756
1757 \section2 Grouping ID-Based Translations
1758
1759 You can assign each ID-based translation a \e label to organize
1760 ID-based entries of large projects into smaller groups.
1761 To assign a \e label to an ID-based entry, add a \c{//@} comment
1762 naming the label, for example in C++:
1763 \code cpp
1764 //% "Open file"
1765 //@ FileOperations
1766 qtTrId("msg.open");
1767 \endcode
1768 Or in QML:
1769 \code qml
1770 //% "Open file"
1771 //@ FileOperations
1772 qsTrId("msg.open");
1773 \endcode
1774 When you open the TS file in \l {Qt Linguist}, the ID-based entries with
1775 the same \e label are grouped together, similar to text-based
1776 entries that are grouped by context.
1777 Any item without a \e label appears under \c{<unnamed label>}.
1778 \note Label names have no effect on lookup or uniqueness: IDs remain globally
1779 unique and can still be loaded via \c{qtTrId("msgid")} without referencing a
1780 label. The label tag is used only to improve the translator’s navigation
1781 and does not change runtime behavior.
1782
1783 \section1 CMake configuration
1784
1785 When building with CMake, use the prefix \c qml_ for .ts files.
1786 For example, \c qml_en.ts. In the CMakeLists.txt file, add the
1787 \l qt_add_translations function, where you list the *.ts files
1788 as values of \c TS_FILES, and set the value of RESOURCE_PREFIX to the
1789 URI of the main.qml file for the project followed by /i18n:
1790
1791 \badcode
1792 qt_add_translations(${CMAKE_PROJECT_NAME}
1793 TS_FILES i18n/qml_de_DE.ts i18n/qml_en_US.ts
1794 RESOURCE_PREFIX Main/i18n
1795 )
1796 \endcode
1797
1798 \section1 Advanced use with qmake
1799
1800 For projects that target a large number of locales, you can remove the
1801 TRANSLATIONS info from the .pro file and, instead, manage the translations
1802 with a separate script. The script can call \c lrelease and \c lupdate for each of
1803 the desired targets.
1804
1805 The updates could be scripted something like this:
1806
1807 \code
1808 lupdate -recursive <project-dir> -ts <project-dir>/i18n/myapp-text_en_GB.ts
1809 lupdate -recursive <project-dir> -ts <project-dir>/i18n/myapp-text_en_US.ts
1810 ...
1811 \endcode
1812
1813 The generation of the final .qm files could be scripted something like this:
1814
1815 \code
1816 lrelease <project-dir>/i18n/myapp-text_en_GB.ts
1817 lrelease <project-dir>/i18n/myapp-text_en_US.ts
1818 ...
1819 \endcode
1820
1821*/
1822
1823/*!
1824 \page linguist-meta-strings-reference.html
1825 \title Meta strings reference
1826 \ingroup internationalization
1827
1828 \previouspage Text ID based translations
1829
1830 \brief Reference guide for meta strings used in Qt's translation system.
1831
1832 Meta strings are special comments that provide additional information to
1833 lupdate and \QL for translation processing. They use specific
1834 prefixes to identify their purpose and can be used in C++, QML, and Python code.
1835
1836 \section1 Meta string syntax overview
1837
1838 Meta strings are special comments that use specific prefixes to provide lupdate
1839 with additional information about translations:
1840
1841 \table
1842 \header
1843 \li Meta String
1844 \li Purpose
1845 \li Usage
1846 \row
1847 \li \c{//:}
1848 \li Extra comment for translators
1849 \li Provides context and guidance to help translators
1850 \row
1851 \li \c{//%}
1852 \li Source text (engineering English)
1853 \li Defines display text for ID-based translations during development
1854 \row
1855 \li \c{//@}
1856 \li Label for grouping
1857 \li Organizes ID-based translations into logical groups
1858 \row
1859 \li \c{//~}
1860 \li Extra key-value metadata
1861 \li Stores additional custom information about the translation
1862 \row
1863 \li \c{// TRANSLATOR}
1864 \li Magic comment for context
1865 \li Provides context information about the class or file
1866 \endtable
1867
1868 \note The \c{//=} meta string for message ID mapping is deprecated and should not be used in new code.
1869
1870 \section1 Translator comments (//:)
1871
1872 Use \c{//:} comments to provide additional context and guidance to translators.
1873 These comments appear in the \QL translation interface and help
1874 translators understand the meaning and usage of the text.
1875
1876 \section2 C++ example
1877 \code cpp
1878 //: Button to navigate backwards in the application
1879 tr("Back");
1880
1881 //: This is a file menu item that opens an existing document.
1882 //: Keep translation short to fit in menu.
1883 tr("Open");
1884 \endcode
1885
1886 \section2 QML example
1887 \code qml
1888 Button {
1889 //: Emergency stop button - must be clearly visible
1890 text: qsTr("STOP")
1891 }
1892 \endcode
1893
1894 \section2 Python example
1895 \code python
1896 #: Button to navigate backwards in the application
1897 self.tr("Back")
1898
1899 #: This is a file menu item that opens an existing document.
1900 #: Keep translation short to fit in menu.
1901 self.tr("Open")
1902 \endcode
1903
1904 Multiple translator comments can be used for the same string and will be
1905 concatenated with newlines in the TS file.
1906
1907 \section2 TS file format
1908
1909 Translator comments appear as \c{<extracomment>} elements in the TS file:
1910
1911 \code xml
1912 <message>
1913 <source>Back</source>
1914 <extracomment>Button to navigate backwards in the application</extracomment>
1915 <translation type="unfinished"></translation>
1916 </message>
1917 \endcode
1918
1919 \section1 Source text (//%)
1920
1921 The \c{//%} meta string defines the \e{engineering English} text that appears
1922 in the user interface during development when using ID-based translations.
1923 This is essential for making the application usable before translations
1924 are complete.
1925
1926 \section2 C++ example
1927 \code cpp
1928 //% "Save Document"
1929 qtTrId("file.save");
1930
1931 //% "Found %n items"
1932 qtTrId("search.results", count);
1933 \endcode
1934
1935 \section2 QML example
1936 \code qml
1937 Text {
1938 //% "Welcome to the application"
1939 text: qsTrId("welcome.message")
1940 }
1941 \endcode
1942
1943 \section2 Important notes
1944 \list
1945 \li Include parameter placeholders (%1, %n) in the source text
1946 \li The source text should be production-ready English
1947 \li Without //% comments, the text ID itself appears in the UI
1948 \endlist
1949
1950 \section2 TS file format
1951
1952 Source text appears as the \c{<source>} element:
1953
1954 \code xml
1955 <message id="file.save">
1956 <source>Save Document</source>
1957 <translation type="unfinished"></translation>
1958 </message>
1959 \endcode
1960
1961 \section1 Labels (//@)
1962
1963 Use \c{//@} meta strings to organize ID-based translations into logical
1964 groups or categories within \QL. This is particularly useful
1965 for large projects with many translation strings.
1966
1967 \note The \c{//@} meta string is only intended for ID-based translations
1968 (qtTrId/qsTrId) and should not be used with text-based translations (tr/qsTr).
1969
1970 \section2 C++ example
1971 \code cpp
1972 //% "New Document"
1973 //@ FileOperations
1974 qtTrId("file.new");
1975
1976 //% "Print Document"
1977 //@ FileOperations
1978 qtTrId("file.print");
1979
1980 //% "Connection failed"
1981 //@ NetworkErrors
1982 qtTrId("network.error.connection");
1983 \endcode
1984
1985 \section2 QML example
1986 \code qml
1987 Button {
1988 //% "Login"
1989 //@ Authentication
1990 text: qsTrId("auth.login")
1991 }
1992 \endcode
1993
1994 \note Labels are not applicable to Python translations since Python only supports
1995 text-based translations (self.tr()) and not ID-based translations.
1996
1997 Strings with the same label appear grouped together in \QL,
1998 making it easier for translators to work on related content.
1999
2000 \section2 TS file format
2001
2002 Labels appear as a \c{label} element:
2003
2004 \code xml
2005 <message id="file.new" label="FileOperations">
2006 <source>New Document</source>
2007 <label>FileOperations</label>
2008 <translation type="unfinished"></translation>
2009 </message>
2010 \endcode
2011
2012 \section1 Extra metadata (//~)
2013
2014 The \c{//~} meta string allows you to attach arbitrary key-value metadata
2015 to translations. This can be used for custom processing or translator
2016 guidance.
2017
2018 \section2 Syntax
2019 \code
2020 //~ key value
2021 //~ key "quoted value with spaces"
2022 \endcode
2023
2024 \section2 C++ example
2025 \code cpp
2026 //% "Error"
2027 //: Critical system error dialog
2028 //~ Severity High
2029 //~ MaxLength "20"
2030 //~ Context "Error dialogs"
2031 qtTrId("system.error");
2032 \endcode
2033
2034 \section2 QML example
2035 \code qml
2036 Text {
2037 //% "Loading..."
2038 //~ Context "Progress indicators"
2039 //~ ShowDuration "true"
2040 text: qsTrId("progress.loading")
2041 }
2042 \endcode
2043
2044 \section2 Python example
2045 \code python
2046 #~ Severity High
2047 #~ Context "Error dialogs"
2048 self.tr("Critical system error")
2049 \endcode
2050
2051 \section2 TS file format
2052
2053 Extra metadata appears as \c{<extra-*>} elements in the TS file and can be
2054 processed by custom tools or translation workflows.
2055
2056 \code xml
2057 <message id="system.error">
2058 <source>Error</source>
2059 <comment>Critical system error dialog</comment>
2060 <translation type="unfinished"></translation>
2061 <extra-Severity>High</extra-Severity>
2062 <extra-MaxLength>20</extra-MaxLength>
2063 <extra-Context>Error dialogs</extra-Context>
2064 </message>
2065 \endcode
2066
2067 \section1 TRANSLATOR magic comments
2068
2069 \c{TRANSLATOR} comments provide context information about a class or
2070 source file to help translators understand where translations are used.
2071
2072 \section2 C++ example
2073 \snippet doc_src_linguist-manual.cpp 5
2074
2075 \section2 QML example
2076 \code qml
2077 // TRANSLATOR LoginDialog Login dialog for user authentication
2078 Item {
2079 Text {
2080 text: qsTr("Username")
2081 }
2082 }
2083 \endcode
2084
2085 \section2 Python example
2086 \code python
2087 # TRANSLATOR MainWindow
2088 #
2089 # Main application window containing the primary user interface.
2090 # Keep button labels concise due to space constraints.
2091 #
2092 class MainWindow(QMainWindow):
2093 def setupUi(self):
2094 self.tr("File") # translations for this context
2095 \endcode
2096
2097 \section2 TS file format
2098
2099 TRANSLATOR comment appear as a \c{<message>} elements with empty source text
2100 on the \c{<context>} element:
2101
2102 \code xml
2103 <context>
2104 <name>Main</name>
2105 <message>
2106 <source></source>
2107 <comment>LoginDialog Login dialog for user authentication</comment>
2108 <translation></translation>
2109 </message>
2110 </context>
2111 \endcode
2112
2113 \section1 Combining meta strings
2114
2115 Meta strings can be combined to provide comprehensive translation metadata:
2116
2117 \section2 Complete C++ example
2118 \code cpp
2119 //: File dialog - confirm destructive action
2120 //: This will permanently delete the selected files
2121 //% "Delete Selected Files"
2122 //@ FileOperations
2123 //~ Severity High
2124 //~ RequiresConfirmation "true"
2125 qtTrId("file.delete.confirm");
2126 \endcode
2127
2128 \section2 Complete QML example
2129 \code qml
2130 Text {
2131 //: Shows current connection status to server
2132 //: Updates automatically every few seconds
2133 //% "Connected to server"
2134 //@ NetworkStatus
2135 //~ UpdateFrequency "5000ms"
2136 //~ Color "green"
2137 text: qsTrId("status.connected")
2138 }
2139 \endcode
2140
2141 \section1 Best practices
2142
2143 \list
2144 \li Use translator comments (//:) generously to provide context
2145 \li Always include source text (//%) for ID-based translations
2146 \li Group related translations using labels (//@) in large projects
2147 \li Place meta strings immediately before the translation function call
2148 \li Keep translator comments clear and concise but informative
2149 \li Use consistent naming for labels and extra metadata keys
2150 \endlist
2151*/