Keep app strings in the platform's resource files

How to do it

On Android, put strings in res/values/strings.xml and translations in folders such as res/values-sv/. Use <plurals> for counts. On Apple platforms, use a String Catalog (.xcstrings). Xcode fills it from your code when you build, and it holds plural variants per language. Write a comment for translators with every string, as Give translators context and a review step says. The default language must hold every key, as Ship a default text for every message says.

Examples

Kotlin example

// res/values/strings.xml
// <plurals name="rooms_booked"><item quantity="one">%d room booked</item><item quantity="other">%d rooms booked</item></plurals>
val label = resources.getQuantityString(R.plurals.rooms_booked, count, count)

Plain text example

// Xcode adds this key and its comment to the String Catalog at build time
let label = String(localized: "\(count) rooms booked", comment: "Status line after a booking. The number is how many rooms.")

How to check

Android Lint runs with HardcodedText and MissingTranslation as errors and passes. On Apple platforms, the build shows no String Catalog entry marked stale or new in a shipped language.

Sources

• Android Developers (Localize your app)
• Apple Developer (Localizing and varying text with a string catalog)

Related rules

• LOC-21 Give translators context and a review step in Localization
• LOC-25 Ship a default text for every message in Localization