UI Settings Module (uiSettings.ts)

Module path: web_rviz/src/uiSettings.ts

Purpose

Manages persisted language/theme preferences and applies static UI translations.

Public API

Language

• en

• zh

ThemeMode

• dark

• light

TranslationKey

Union of translation keys derived from the built-in English translation table.

loadLanguage(): Language / saveLanguage(language): void

Loads or stores the current UI language in localStorage.

loadTheme(): ThemeMode / saveTheme(theme): void

Loads or stores the current UI theme in localStorage.

t(language, key, vars = {})

Returns the translated string for key and performs {name} placeholder substitution from vars.

applyStaticTranslations(language): void

Updates document.documentElement.lang, document.title, and every element marked with data-i18n.

applyTheme(theme): void

Writes the current theme to document.documentElement.dataset.theme for CSS selectors to consume.

Behavior Notes

• Default language is zh when no prior preference exists.

• Default theme is light when no prior preference exists.

• t() falls back to the English string first, then the raw key.

• applyStaticTranslations() only updates static labels; dynamic runtime strings should still go through t() when rendered.