| Index: pkg/intl/README.md
|
| diff --git a/pkg/intl/README.md b/pkg/intl/README.md
|
| deleted file mode 100644
|
| index 18951c750a0f0193d350509557b6b0a5decbc602..0000000000000000000000000000000000000000
|
| --- a/pkg/intl/README.md
|
| +++ /dev/null
|
| @@ -1,300 +0,0 @@
|
| -Intl
|
| -====
|
| -
|
| -This package provides internationalization and localization facilities,
|
| -including message translation, plurals and genders, date/number formatting
|
| -and parsing, and bidirectional text.
|
| -
|
| -## General
|
| -The most important library is [intl][intl_lib]. It defines the [Intl][Intl]
|
| -class, with the default locale and methods for accessing most of the
|
| -internationalization mechanisms. This library also defines the
|
| -[DateFormat][DateFormat], [NumberFormat][NumberFormat], and
|
| -[BidiFormatter][BidiFormatter] classes.
|
| -
|
| -## Current locale
|
| -
|
| -The package has a single current locale, called [defaultLocale][defaultLocale].
|
| -Operations will use that locale unless told to do otherwise.
|
| -
|
| -To set the global locale, you can explicitly set it, e.g.
|
| -
|
| - Intl.defaultLocale = 'pt_BR';
|
| -
|
| -or get it from the browser by
|
| -
|
| - import "package:intl/intl_browser.dart";
|
| - ...
|
| - findSystemLocale().then(runTheRestOfMyProgram);
|
| -
|
| -To temporarily override the current locale, pass the operation
|
| -to [withLocale][withLocale].
|
| -
|
| - Intl.withLocale('fr', () => print(myLocalizedMessage());
|
| -
|
| -To override it for a very specific operation you can create a format object in
|
| -a specific locale, or pass in the locale as a parameter to methods.
|
| -
|
| - var format = new DateFormat.yMd("ar");
|
| - var dateString = format.format(new DateTime.now());
|
| - print(myMessage(dateString, locale: 'ar');
|
| -
|
| -## Initialization
|
| -
|
| -All the different types of locale data require an async initialization step
|
| -to make
|
| -sure the data is available. This reduces the size of the application by only
|
| -loading the
|
| -data that is actually required.
|
| -
|
| -Each different area of internationalization (messages, dates, numbers) requires
|
| -a separate initialization process. That way, if the application only needs to
|
| -format dates, it doesn't need to take the time or space to load up messages,
|
| -numbers, or other things it may not need.
|
| -
|
| -With messages, there is also a need to import a file that won't exist until
|
| -the code generation step has been run. This can be awkward, but can be worked
|
| -around by creating a stub `messages_all.dart` file, running an empty translation
|
| -step, or commenting out the import until translations are available.
|
| -See "Extracting and Using Translated Messages"
|
| -
|
| -## Messages
|
| -
|
| -Messages to be localized are written as functions that return the result of
|
| -an [Intl.message][Intl.message] call.
|
| -
|
| - String continueMessage() => Intl.message(
|
| - "Hit any key to continue",
|
| - name: "continueMessage",
|
| - args: [],
|
| - desc: "Explains that we will not proceed further until "
|
| - "the user presses a key");
|
| - print(continueMessage());
|
| -
|
| -This provides, in addition to the basic message string, a name, a
|
| -description for translators, the arguments used in the message, and
|
| -examples. The `name` and `args` parameters are required, and must
|
| -match the name and arguments list of the function. In the future we
|
| -hope to have these provided automatically.
|
| -
|
| -This can be run in the program before any translation has been done,
|
| -and will just return the message string. It can also be extracted to a
|
| -file and then be made to return a translated version without modifying
|
| -the original program. See "Extracting Messages" below for more
|
| -details.
|
| -
|
| -The purpose of wrapping the message in a function is to allow it to
|
| -have parameters which can be used in the result. The message string is
|
| -allowed to use a restricted form of Dart string interpolation, where
|
| -only the function's parameters can be used, and only in simple
|
| -expressions. Local variables cannot be used, and neither can
|
| -expressions with curly braces. Only the message string can have
|
| -interpolation. The name, desc, args, and examples must be literals and
|
| -not contain interpolations. Only the args parameter can refer to
|
| -variables, and it should list exactly the function parameters. If you
|
| -are passing numbers or dates and you want them formatted, you must do
|
| -the formatting outside the function and pass the formatted string into
|
| -the message.
|
| -
|
| - greetingMessage(name) => Intl.message(
|
| - "Hello $name!",
|
| - name: "greetingMessage",
|
| - args: [name],
|
| - desc: "Greet the user as they first open the application",
|
| - examples: {'name': "Emily"});
|
| - print(greetingMessage('Dan'));
|
| -
|
| -There is one special class of complex expressions allowed in the
|
| -message string, for plurals and genders.
|
| -
|
| - remainingEmailsMessage(int howMany, String userName) =>
|
| - Intl.message(
|
| - "${Intl.plural(howMany,
|
| - zero: 'There are no emails left for $userName.',
|
| - one: 'There is one email left for $userName.',
|
| - other: 'There are $howMany emails left for $userName.')}",
|
| - name: "remainingEmailsMessage",
|
| - args: [howMany, userName],
|
| - desc: "How many emails remain after archiving.",
|
| - examples: {'number': 42, 'userName': 'Fred'});
|
| -
|
| - print(remainingEmailsMessage(1, "Fred"));
|
| -
|
| -However, since the typical usage for a plural or gender is for it to
|
| -be at the top-level, we can also omit the [Intl.message][Intl.message] call and
|
| -provide its parameters to the [Intl.plural][Intl.plural] call instead.
|
| -
|
| - remainingEmailsMessage(int howMany, String userName) =>
|
| - Intl.plural(
|
| - howMany,
|
| - zero: 'There are no emails left for $userName.',
|
| - one: 'There is one email left for $userName.',
|
| - other: 'There are $howMany emails left for $userName.'),
|
| - name: "remainingEmailsMessage",
|
| - args: [howMany, userName],
|
| - desc: "How many emails remain after archiving.",
|
| - examples: {'number': 42, 'userName': 'Fred'});
|
| -
|
| -Similarly, there is an [Intl.gender][Intl.gender] message, and plurals
|
| -and genders can be nested.
|
| -
|
| - notOnlineMessage(String userName, String userGender) =>
|
| - Intl.gender(
|
| - userGender,
|
| - male: '$userName is unavailable because he is not online.',
|
| - female: '$userName is unavailable because she is not online.',
|
| - other: '$userName is unavailable because they are not online'),
|
| - name: "notOnlineMessage",
|
| - args: [userName, userGender],
|
| - desc: "The user is not available to hangout.",
|
| - examples: {{'userGender': 'male', 'userName': 'Fred'},
|
| - {'userGender': 'female', 'userName' : 'Alice'}});
|
| -
|
| -It's recommended to use complete sentences in the sub-messages to keep
|
| -the structure as simple as possible for the translators.
|
| -
|
| -## Extracting And Using Translated Messages
|
| -
|
| -When your program contains messages that need translation, these must
|
| -be extracted from the program source, sent to human translators, and the
|
| -results need to be incorporated.
|
| -
|
| -To extract messages, run the `extract_to_arb.dart` program.
|
| -
|
| - pub run intl:extract_to_arb --output-dir=target/directory
|
| - my_program.dart more_of_my_program.dart
|
| -
|
| -This will produce a file `intl_messages.arb` with the messages from
|
| -all of these programs. an [ARB]
|
| -(https://code.google.com/p/arb/wiki/ApplicationResourceBundleSpecification)
|
| -format file which can be used for input to translation tools like
|
| -[Google Translator Toolkit](https://translate.google.com/toolkit/)
|
| -The resulting translations can be used to generate a set of libraries
|
| -using the `generate_from_arb.dart` program.
|
| -
|
| -This expects to receive a series of files, one per
|
| -locale.
|
| -
|
| - pub run intl:generate_from_arb --generated_file_prefix=<prefix>
|
| - <my_dart_files> <translated_ARB_files>
|
| -
|
| -This will generate Dart libraries, one per locale, which contain the
|
| -translated versions. Your Dart libraries can import the primary file,
|
| -named `<prefix>messages_all.dart`, and then call the initialization
|
| -for a specific locale. Once that's done, any
|
| -[Intl.message][Intl.message] calls made in the context of that locale
|
| -will automatically print the translated version instead of the
|
| -original.
|
| -
|
| - import "my_prefix_messages_all.dart";
|
| - ...
|
| - initializeMessages("dk").then(printSomeMessages);
|
| -
|
| -Once the future returned from the initialization call returns, the
|
| -message data is available.
|
| -
|
| -## Number Formatting and Parsing
|
| -
|
| -To format a number, create a NumberFormat instance.
|
| -
|
| - var f = new NumberFormat("###.0#", "en_US");
|
| - print(f.format(12.345));
|
| - ==> 12.34
|
| -
|
| -The locale parameter is optional. If omitted, then it will use the
|
| -current locale. The format string is as described in
|
| -[NumberFormat][NumberFormat]
|
| -
|
| -It's also possible to access the number symbol data for the current
|
| -locale, which provides information as to the various separator
|
| -characters, patterns, and other information used for formatting, as
|
| -
|
| - f.symbols
|
| -
|
| -Current known limitations are that the currency format will only print
|
| -the name of the currency, and does not support currency symbols, and
|
| -that the scientific format does not really agree with scientific
|
| -notation. Number parsing is not yet implemented.
|
| -
|
| -Note that before doing any number formatting for a particular locale
|
| -you must load the appropriate data by calling
|
| -
|
| - import 'package:intl/number_symbols_data_local.dart';
|
| - ...
|
| - initializeNumberFormatting(localeName, null).then(formatNumbers);
|
| -
|
| -Once the future returned from the initialization call returns, the
|
| -formatting data is available. Note that right now this includes all
|
| -the data for a locales. We expect to make this use deferred loading to
|
| -reduce code size.
|
| -
|
| -## Date Formatting and Parsing
|
| -
|
| -To format a [DateTime][DateTime], create a [DateFormat][DateFormat]
|
| -instance. These can be created using a set of commonly used skeletons
|
| -taken from ICU/CLDR or using an explicit pattern. For details on the
|
| -supported skeletons and patterns see [DateFormat][DateFormat].
|
| -
|
| - new DateFormat.yMMMMEEEEd().format(aDateTime);
|
| - ==> 'Wednesday, January 10, 2012'
|
| - new DateFormat("EEEEE", "en_US").format(aDateTime);
|
| - ==> 'Wednesday'
|
| - new DateFormat("EEEEE", "ln").format(aDateTime);
|
| - ==> 'mokɔlɔ mwa mísáto'
|
| -
|
| -You can also parse dates using the same skeletons or patterns.
|
| -
|
| - new DateFormat.yMd("en_US").parse("1/10/2012");
|
| - new DateFormat("Hms", "en_US").parse('14:23:01');
|
| -
|
| -Skeletons can be combined, the main use being to print a full date and
|
| -time, e.g.
|
| -
|
| - new DateFormat.yMEd().add_jms().format(new DateTime.now());
|
| - ==> 'Thu, 5/23/2013 10:21:47 AM'
|
| -
|
| -Known limitations: Time zones are not yet supported. Dart
|
| -[DateTime][DateTime] objects don't have a time zone, so are either
|
| -local or UTC. Formatting and parsing Durations is not yet implemented.
|
| -
|
| -Note that before doing any DateTime formatting for a particular
|
| -locale, you must load the appropriate data by calling.
|
| -
|
| - import 'package:intl/date_symbol_data_local.dart';
|
| - ...
|
| - initializeDateFormatting("de_DE", null).then(formatDates);
|
| -
|
| -Once the future returned from the initialization call returns, the
|
| -formatting data is available.
|
| -
|
| -There are other mechanisms for loading the date formatting data
|
| -implemented, but we expect to deprecate those in favor of having the
|
| -data in a library as in the above, and using deferred loading to only
|
| -load the portions that are needed. For the time being, this will
|
| -include all of the data, which will increase code size.
|
| -
|
| -## Bidirectional Text
|
| -
|
| -The class [BidiFormatter][BidiFormatter] provides utilities for
|
| -working with Bidirectional text. We can wrap the string with unicode
|
| -directional indicator characters or with an HTML span to indicate
|
| -direction. The direction can be specified with the
|
| -[RTL][BidiFormatter.RTL] and [LTR][BidiFormatter.LTR] constructors, or
|
| -detected from the text.
|
| -
|
| - new BidiFormatter.RTL().wrapWithUnicode('xyz');
|
| - new BidiFormatter.RTL().wrapWithSpan('xyz');
|
| -
|
| -[intl_lib]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl
|
| -[Intl]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl
|
| -[DateFormat]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.DateFormat
|
| -[NumberFormat]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.NumberFormat
|
| -[withLocale]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.Intl#id_withLocale
|
| -[defaultLocale]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.Intl#id_defaultLocale
|
| -[Intl.message]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.Intl#id_message
|
| -[Intl.plural]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.Intl#id_plural
|
| -[Intl.gender]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.Intl#id_gender
|
| -[DateTime]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/dart:core.DateTime
|
| -[BidiFormatter]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.BidiFormatter
|
| -[BidiFormatter.RTL]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.BidiFormatter#id_BidiFormatter-RTL
|
| -[BidiFormatter.LTR]: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/intl/intl.BidiFormatter#id_BidiFormatter-LTR
|
|
|