User Interface Language Management

MUI allows your applications to manage user interface languages in two ways. An application can use a simple approach to language management by defaulting to the operating system language settings. Alternatively, the application can support its own languages from which the user can select. The MUI API also allows your application direct access to languages and language lists supported by the operating system and maintained by the resource loader. The remainder of this topic defines the system-supported languages and the language fallback mechanism.

Languages Maintained by the Operating System

System Default UI Language/Install Language

The system default UI language is the language of the localized version used to set up Windows. All menus, dialog boxes, error messages, and help files are represented in this language, except when the user selects a different language.

On WindowsВ Vista and later, the system default UI language is known as the «install language» and plays a more limited role. For most purposes, it is superseded by the system preferred UI languages. However, in certain contexts it is useful to have a single install language that is always known to be fully supported.

No MUI function is available to set the system default UI language. To retrieve this language, the application can call GetSystemDefaultUILanguage.

System UI Language

The operating system defines the system UI language as a user interface language that can be set by an administrator in the Advanced tab of the regional and language options portion of Control Panel. The operating system uses this language if the current user has not made specific language settings or if no active account is logged in. The language can be changed only if more than one user interface language is installed on the computer.

The operating system must be rebooted for all users and services to see the effect of the language change.

No MUI function is available to set the system UI language. To retrieve this value, an application targeted at WindowsВ Vista and later can call GetSystemPreferredUILanguages and obtain the first language in the system preferred UI languages list. Applications targeted at pre-WindowsВ Vista operating systems cannot use GetSystemPreferredUILanguages and should be based on the assumption that the system UI language is always the same as the system default UI language.

User UI Language

The user UI language determines the user interface language used for menus, dialog boxes, help files, and so forth. It can be set by the current user in the Language tab of the regional and language options portion of Control Panel. This language can be changed only if more than one user interface language is installed on the computer. Note that the user will have to log off and then log back on to see the effect. For example, a multinational corporation wants to deploy Windows in all of its subsidiaries. The company creates a global install job, which installs the English language version of Windows on all clients, regardless of location. At the same time, it installs specific language modules depending on the organizational unit of which a computer is a member. When the user logs on the first time to a newly installed operating system, Windows appears as a localized version.

On WindowsВ Vista and later, the user UI language is the first language in the user preferred UI languages list. Note that fallback languages can be used if particular resources are not available in this language.

On pre-WindowsВ Vista operating systems, the user UI language is usually the same as the system default UI language. However, for Windows MUI, the two languages can be different.

To retrieve the user UI language, an application can call GetUserDefaultUILanguage or GetUserPreferredUILanguages. The application cannot change the user UI language, as there is no function to set it.

Language Lists Maintained by the Operating System

System Preferred UI Languages List

The resource loader maintains a system preferred UI languages list. Included in this list are languages preferred by the operating system for its own resources, such as menus and dialogs, messages, INF files, and help files. The list is made up of the system default UI language and the system UI language and their fallbacks. An application can retrieve system preferred UI languages by calling GetSystemPreferredUILanguages.

User Preferred UI Languages List

The resource loader uses a user preferred UI languages list that includes languages that the user prefers. The resource loader uses resources matching languages from this list, if available, for a particular application thread. These languages take precedence over any system preferences. To retrieve user preferred UI languages, your application can call GetUserPreferredUILanguages.

Process Preferred UI Languages List

On WindowsВ Vista and later, the resource loader maintains a process preferred UI languages list consisting of up to five valid languages set by a running process for a MUI application. The languages can be set by the application with a call to SetProcessPreferredUILanguages. The application can retrieve the languages by calling GetProcessPreferredUILanguages.

Thread Preferred UI Languages List

On WindowsВ Vista and later, the resource loader uses a thread preferred UI languages list that consists of up to five valid languages set by a thread in a running process for a MUI application. These languages are used to customize the application user interface languages and make them different from the operating system language. The thread preferred UI languages list is based on the user preferred UI languages, the system preferred UI languages, and the system default UI language.

To set the thread preferred UI languages, the application should call SetThreadPreferredUILanguages. To retrieve these languages, the application calls GetThreadPreferredUILanguages.

Neutral Language Representation

A neutral language is represented as the language alone, without region or locale. For example, the neutral representation of the English (Canada) language, en-CA, is represented as «en». Even though a neutral language is not associated with the aspects of a region or locale, you can associate it with a resource set. Typically, a neutral language resource is based on the use in the most prevalent region for the language.

As an illustration, suppose that your MUI application localizes German language resources for German (Switzerland) represented as de-CH and German (Austria) represented as de-AT, while building a full set of resources for German (Germany) represented as de-DE. You must make decisions for this application considering entire resource files. If the application duplicates the de-DE resources as neutral language resources, it must provide a fallback language for the resource loader. If the loader does not find a particular language-specific resource file for de-CH or for de-AT, it falls back to the language-neutral «de» resources. These resources are most likely more appropriate than resources for a completely different language, for example, English (United States), which are the only other possible fallbacks.

As another example, an application might not localize at all for Belize. However, support of a language preference of English (Belize), represented as en-BZ, allows the application to fall back to «en» resources.

Language Fallback in the Resource Loader

WindowsВ Vista and later arrange user interface language settings in a preordered fallback language list used by the resource loader. To form the list, the operating system combines several languages, in the order shown:

Thread preferred UI languages, consisting of thread user interface language and its neutral form. Examples are fr-FR for French (France) and its neutral form «fr» and es-ES for Spanish (Spain) and its neutral form «es».

Process preferred UI languages, consisting of process user interface language and its neutral form. An example is de-DE for German (Germany) and its neutral form «de».

User UI language and its neutral form. An example is ja-JP for Japanese (Japan) and its neutral form «ja».

System UI language and its neutral form. An example is it-IT for Italian (Italy) and its neutral form «it».

This language is only included in the fallback list when the user UI language is not set.

System default UI language and its neutral form. An example is es-ES for Spanish (Spain) and its neutral form «es».

The following shows the merged fallback list. Note that the duplication of languages, for example, es-ES and es, is eliminated. Since the example sets the user UI language to ja-JP, the system UI language does not appear in the merged fallback list.

fr-FR, fr, es-ES, es, de-DE, de, ja-JP, ja

When loading resources for a MUI application, the resource loader tries to select one of the files matching the thread preferred UI languages list for the currently running application thread. If the resource loader cannot find a direct match between a selected language and the first language-specific resource in the merged fallback list, it checks the subsequent languages in the list until it finds an acceptable fallback.

If the resource loader finds no file that it needs, it must use a «guaranteed good» fallback language. For the MUI resource technology, the resource loader determines the fallback language from the provided resource configuration data. For more information, see MUI Resource Management.

Использование многоязыкового интерфейса пользователя

В этом разделе описывается использование функций многоязыкового пользовательского интерфейса (MUI) для проектирования и реализации приложений. Ниже приведены аспекты технологии MUI, которые будут воспроизводиться на большинстве этапов жизненного цикла приложения.

• Разработка приложений, включая подготовку ресурсов, настройку языковых настроек приложения, Поиск и загрузку ресурсов.
• Сборка и локализация приложения
• Развертывание приложения

Ниже приведены некоторые вопросы, которые следует учитывать при проектировании и реализации приложения MUI.

• Какие версии Windows будет поддерживать приложение?
• На каких языках будет локализовано приложение?
• Должны ли параметры языка приложения всегда соответствовать языковым параметрам операционной системы или пользователь приложения может устанавливать определенные языки?
• Какой тип ресурсов пользовательского интерфейса используется приложением и где они хранятся?

Этот раздел содержит следующие темы. В описаниях предполагается приложение MUI, предназначенное для Windows Vista и более поздних версий. Ресурсы для этого приложения — это ресурсы Win32 с ресурсами, зависящими от языка, и исполняемым кодом, размещенным в отдельных файлах Win32 PE. При необходимости добавляются специальные рекомендации по поддержке операционных систем, предшествующих Windows Vista, или для различных типов ресурсов.

Using Multilingual User Interface

This section describes how to use Multilingual User Interface (MUI) functionality to design and implement your applications. The following are aspects of MUI technology that will come into play at most stages of the application lifecycle.

• Application development, including resource preparation, setting of application language preferences, finding and loading of resources
• Building and localizing the application
• Deploying the application

Here are some questions to consider when designing and implementing a MUI application.

• What are the versions of Windows that the application will support?
• In what languages will the application be localized?
• Should the application language settings always follow language settings for the operating system, or should the application user be able to set specific languages?
• What type of user interface resources does the application use and where are they stored?

This section includes the following topics. The descriptions assume a MUI application targeted at WindowsВ Vista and later. The resources for this application are Win32 resources, with language-specific resources and executable code residing in separate Win32 PE files. Special considerations for support of pre-WindowsВ Vista operating systems or for different types of resources are added as appropriate.

About Multilingual User Interface

Multilingual User Interface (MUI) is a technology that provides users a localized user interface for globalized applications and user interface language resource management in the Windows operating system. Support is provided for adding MUI functionality to globalized applications to run on WindowsВ Vista and later, as well as many pre-WindowsВ Vista operating systems. The MUI localization and resource management models enhance development, testing, and support for world-ready software.

Features of MUI technology include:

• Simplified language management for software localization. MUI allows the language settings for the operating system to be changed to a supported language according to user preferences.
• An innovative resource technology based on the splitting of the application code binary from language resource files. You can add resources for an additional language without needing to recompile or relink your application. Additional localized resources become optional add-ins.
• Complete application programming interface (API). WindowsВ Vista and later expose the MUI API for you to use in adding MUI functionality to globalized applications. Language management functions enable your applications to support a wide variety of user interface languages. The API also includes resource loading functions that enable the resource loader to load resources on WindowsВ Vista and later, as well as pre-WindowsВ Vista operating systems.
• A set of language pack management tools that provide flexibility in international deployment image management. These tools are not targeted at developers and thus are not covered in the SDK. More information can be found in the Windows Automated Installation Kit available on Technet.

The most visible benefit of MUI is that multiple users can share the same workstation and view the user interface in different languages. Corporations and OEMs will benefit from the capability they have to roll out, support, and maintain multilingual images with a single installation. But perhaps the main benefit of MUI comes in the efficiencies gained when developing, building and servicing your application. You can ship one core functionality binary applicable to all platforms, independent of UI language, which significantly reduces development and testing efforts. If you have to issue an update or a service pack, it will apply to all supported languages with no additional engineering effort. Later support for additional languages becomes a localization project instead of a full software development project.