使用Requirejs动态加载区域设置文件

时间:2013-10-27 18:13:33

标签: javascript internationalization requirejs amd js-amd

我有一个基于RequireJS的单页Marionette应用程序需要支持翻译。

我的目标是为每种语言提供一个字典文件,并根据登录用户的配置加载相关文件。

由于大多数用户都会使用英语,我想在构建期间在应用程序中捆绑英语词典(使用r.js)。

我写了一个小的Translator模块,它基本上包装了jed.js(我用于i18n的库):

//in myTranslator.js
define(function (require) {
    "use strict";

    var Jed = require("jed");
    var localeData = require("json!locales/en_US.json");

    var Translator = function () {
        var i18n = new Jed({
            "domain": "messages",
            "locale_data": localeData
        });
        return i18n;
    };
    return Translator;
});

//in app.js
define(function(require){
    var Translator = require("myTranslator");
    var translator = new Translator();
});

如您所见,语言环境数据是从静态文件加载的。 我希望能够将语言环境传递给Translator构造函数,并在此基础上加载正确的JSON文件。

如何将英语JSON与建成项目捆绑在一起?

2 个答案:

答案 0 :(得分:4)

您应该能够检查用户设置,构造依赖关系字符串,将其传递给Translator,然后使用它而不是localeData - r.js将忽略动态依赖关系,但应捆绑EN语言环境。

if ( userLocale && userLocale !== 'en_US' ) {

    var localePath = 'json!locales/' + userLocale + '.json';
    require([ localePath ], function( locale ) {
        var translator = new Translator( locale );
    });

}

和内部翻译:{{1​​}}。

(或在翻译模块中执行相同操作,如"locale_data": passedData || englishData

理论上它应该有用,虽然你cannot use simplified CommonJS在这里并且应该使用callback-require,否则你会得到Module name ... has not been loaded yet for context错误。

答案 1 :(得分:1)

这是我最终做的解决方案。 它运行得非常好,我也学会了使用$ .Deferred这很棒!

对我来说,关键是在代码中使用require text插件作为加载器。

默认语言环境被设置为依赖项,也就是它在构建中被烘焙。

解释见以下代码:

//in translator.js
define(function (require) {
    "use strict";

    var $ = require("jquery");
    var _ = require("underscore");
    var Jed = require("jed");
    var text = require("text");
    var defaultDictionary = require("json!locales/en_US.json");

    var Translator;

    Translator = (function () {
        var DEFAULT_LOCALE = "en_US";
        var defaultLocaleData = {
            locale: DEFAULT_LOCALE,
            dictionary: defaultDictionary
        };

        var createTranslator = function (localeData) {
            //create the actual Jed instance with the relevant dictionary
            var i18n = new Jed({
                "domain": "messages",
                "locale_data": localeData.dictionary
            });
            return i18n;
        };
        var parseLocaleDictionary = function (locale, dictionary) {
            //parse the dictionary JSON string loaded by text plugin...
            //handle errors in parsing if needed
        };
        //get to work here
        var getTranslatorForLocale = function (locale) {
            //$gettingData promise will be resolved when data for Jed is loaded and ready
            var $gettingData = $.Deferred();
            //$creatingTranslator promise will be returned to caller and will be resolved when everything's done
            var $creatingTranslator = $.Deferred();

            if (!locale || locale === DEFAULT_LOCALE) {
                //default locale, so resolve right away because we required it already
                $gettingData.resolve(defaultLocaleData);
            }
            else {
                //need to load the dictionary from here
                var dictionaryUrl = require.toUrl("locales/" + locale + ".json");
                //this is the dynamic loading
                text.get(
                    dictionaryUrl,
                    function (dictionary) {
                        //if successful, parse the JSON string and use that dictionary
                        var localeData = parseLocaleDictionary(locale, dictionary);
                        $gettingData.resolve(localeData);
                    },
                    function (error) {
                        //on load error, use the default and resolve promise
                        $gettingData.resolve(defaultLocaleData);
                    });
            }

            //once the data is ready, we can create the translator instance
            $gettingData.done(function (localeData) {
                var i18n = createTranslator(localeData);
                //notify caller that translator is ready
                $creatingTranslator.resolve(i18n);
            });

            return $creatingTranslator.promise();
        };

        return {
            //this function is returned to the user of Translator
            getTranslator: function (locale) {
                var $gettingTranslator = getTranslatorForLocale(locale);
                return $gettingTranslator;
            }
        };
    }());

    return Translator;
});
//in app.js
define(function (require) {
    var Translator = require("translator");
    //in app.js
    var myTranslator;
    var userLocale = "fr_FR";
    //this is a promise that will be resolved when translator is ready
    var $getTranslator = Translator.getTranslator(userLocale);
    //when translator is ready, store it
    $getTranslator.done(function (translator) {
        myTranslator = translator;
    });
    //...
});