i18n — language packs

Two capabilities — don't mix them up:

1. Full UI language pack (type: "i18n"): translate the whole interface into a new language
2. Plugin self-contained strings (locales/, available to any plugin type): translate only your own plugin

---

1. Full UI language pack (type: "i18n")

{
  "id": "example.i18n.japanese",
  "name": "日本語 UI 言語パック",
  "version": "1.0.0",
  "target_app_version": "0.2",
  "author": "TransBox",
  "type": "i18n",
  "language_code": "ja-JP",
  "language_name": "日本語",
  "entrypoint": "ja.json"
}

• ja.json is a flat key-value dictionary ({"settings.title": "設定", ...}).
• Fallback order for missing entries: en-US → zh-CN.
• Language packs are mutually exclusive (only one UI language at a time).
• Defaults to enabled: false.
• Enabling it switches the UI language immediately; disabling it falls back safely.

Reference: extensions/example_i18n_japanese/.

---

2. Plugin self-contained strings in locales/ (recommended for every plugin)

Any plugin type (assistant / theme / tool …) may provide, in its plugin root directory:

my_plugin/
├── locales/
│   ├── zh-CN.json     # file name → language code
│   └── en-US.json

{
  "_meta": {
    "plugin_id": "community.assistant.interview_copilot",
    "code": "zh-CN",
    "name": "中文 (简体)",
    "short_label": "中"
  },
  "plugin.community.assistant.interview_copilot.name": "AI 面试答题助手",
  "plugin.community.assistant.interview_copilot.desc": "……",
  "plugin.community.assistant.interview_copilot.tab_title": "AI 面试助手",
  "copilot.title": "AI 面试答题助手",
  "copilot.stealth_shield": "防录屏保护"
}

Rules:

• The host detects and mounts them automatically during the scan, no code required.
• When the user switches language, entries are merged gracefully in the order target language → plugin en-US → plugin zh-CN.
• _meta is a metadata block (plugin_id / code / name / short_label) and is not treated as a string entry.
• Reserved prefixes plugin.<plugin_id>.name / .desc / .tab_title: the plugin's display name / description / title in the Plugin Hub list and on the settings tab follow the language.
• All other keys (such as copilot.*) are your own namespace — use them freely.
• Read them in QML with I18n.t("copilot.title"); the settings tab title (tab_title) responds automatically.

Never modify the host core string tables (src/transbox/ui/locales/*.json) — language packs and plugin strings are incremental overrides, not replacements.

---

Self-check

• [ ] At least zh-CN.json and en-US.json under locales/
• [ ] String prefixes don't collide with other plugins (use plugin.<plugin_id>.* or your own namespace)
• [ ] Switch to the English interface: the plugin card name/description and settings-page copy all turn English, with no Chinese left over

---

Related

• glossary — a glossary is a "translation-specific term list", not UI translation
• Layout & mod.json
• Example library