react-native-localize

What is react-native-localize?

The react-native-localize package provides localization utilities for React Native applications. It helps in handling various localization tasks such as determining the user's locale, timezone, and country, as well as formatting numbers, dates, and times according to the user's locale.

What are react-native-localize's main functionalities?

Get User's Locale

This feature allows you to get the list of locales preferred by the user. The code sample retrieves the user's preferred locales and logs them to the console.

const { getLocales } = require('react-native-localize');
const locales = getLocales();
console.log(locales);

Get User's Timezone

This feature allows you to get the user's current timezone. The code sample retrieves the user's timezone and logs it to the console.

const { getTimeZone } = require('react-native-localize');
const timeZone = getTimeZone();
console.log(timeZone);

Get User's Country

This feature allows you to get the user's current country. The code sample retrieves the user's country and logs it to the console.

const { getCountry } = require('react-native-localize');
const country = getCountry();
console.log(country);

Format Number

This feature allows you to get the number formatting settings for the user's locale. The code sample retrieves the decimal and grouping separators and logs them to the console.

const { getNumberFormatSettings } = require('react-native-localize');
const { decimalSeparator, groupingSeparator } = getNumberFormatSettings();
console.log(`Decimal Separator: ${decimalSeparator}, Grouping Separator: ${groupingSeparator}`);

Handle Localization Changes

This feature allows you to handle changes in localization settings. The code sample adds an event listener that logs a message when localization settings change.

const { addEventListener, removeEventListener } = require('react-native-localize');
const handleLocalizationChange = () => {
  console.log('Localization settings changed');
};
addEventListener('change', handleLocalizationChange);
// To remove the listener
// removeEventListener('change', handleLocalizationChange);

Other packages similar to react-native-localize

i18next

i18next is a popular internationalization framework for JavaScript that provides a complete solution for localizing your app. It supports multiple languages, pluralization, and interpolation. Compared to react-native-localize, i18next offers more comprehensive internationalization features but requires more setup.

react-intl

react-intl is a library for internationalizing React applications. It provides components and an API to format dates, numbers, and strings, and to handle pluralization. While react-intl focuses on formatting and message handling, react-native-localize provides more utilities for determining the user's locale and timezone.

expo-localization

expo-localization is a package from the Expo ecosystem that provides localization utilities similar to react-native-localize. It can determine the user's locale, timezone, and country. However, expo-localization is designed to work seamlessly with Expo projects, whereas react-native-localize can be used in any React Native project.

README

🌍  react-native-localize

A toolbox for your React Native app localization.

Support

This library follows the React Native releases support policy.
It is supporting the latest version, and the two previous minor series.

Setup

$ npm install --save react-native-localize
# --- or ---
$ yarn add react-native-localize

Don't forget to run pod install after that !

Web support

This package supports react-native-web. Follow their official guide to configure webpack.

Debugging

As this library uses synchronous native methods, remote debugging (e.g. with Chrome) is no longer possible.
Instead, you should use Flipper 🐬.

Basic usage example

import { getCurrencies, getLocales } from "react-native-localize";

console.log(getLocales());
console.log(getCurrencies());

API

getLocales()

Returns the user preferred locales, in order.

Method type

type getLocales = () => Array<{
  languageCode: string;
  scriptCode?: string;
  countryCode: string;
  languageTag: string;
  isRTL: boolean;
}>;

Usage example

import { getLocales } from "react-native-localize";

console.log(getLocales());
/* -> [
  { countryCode: "GB", languageTag: "en-GB", languageCode: "en", isRTL: false },
  { countryCode: "US", languageTag: "en-US", languageCode: "en", isRTL: false },
  { countryCode: "FR", languageTag: "fr-FR", languageCode: "fr", isRTL: false },
] */

---

getNumberFormatSettings()

Returns number formatting settings.

Method type

type getNumberFormatSettings = () => {
  decimalSeparator: string;
  groupingSeparator: string;
};

Usage example

import { getNumberFormatSettings } from "react-native-localize";

console.log(getNumberFormatSettings());
/* -> {
  decimalSeparator: ".",
  groupingSeparator: ",",
} */

---

getCurrencies()

Returns the user preferred currency codes, in order.

Method type

type getCurrencies = () => string[];

Usage example

import { getCurrencies } from "react-native-localize";

console.log(getCurrencies());
// -> ["EUR", "GBP", "USD"]

---

getCountry()

Returns the user current country code (based on its device locale, not on its position).

Method type

type getCountry = () => string;

Usage example

import { getCountry } from "react-native-localize";

console.log(getCountry());
// -> "FR"

Note

Devices using Latin American regional settings will return "UN" instead of "419", as the latter is not a standard country code.

---

getCalendar()

Returns the user preferred calendar format.

Method type

type getCalendar = () =>
  | "gregorian"
  | "buddhist"
  | "coptic"
  | "ethiopic"
  | "ethiopic-amete-alem"
  | "hebrew"
  | "indian"
  | "islamic"
  | "islamic-umm-al-qura"
  | "islamic-civil"
  | "islamic-tabular"
  | "iso8601"
  | "japanese"
  | "persian";

Usage example

import { getCalendar } from "react-native-localize";

console.log(getCalendar());
// -> "gregorian"

---

getTemperatureUnit()

Returns the user preferred temperature unit.

Method type

type getTemperatureUnit = () => "celsius" | "fahrenheit";

Usage example

import { getTemperatureUnit } from "react-native-localize";

console.log(getTemperatureUnit());
// -> "celsius"

---

getTimeZone()

Returns the user preferred timezone (based on its device settings, not on its position).

Method type

type getTimeZone = () => string;

Usage example

import { getTimeZone } from "react-native-localize";

console.log(getTimeZone());
// -> "Europe/Paris"

---

uses24HourClock()

Returns true if the user prefers 24h clock format, false if they prefer 12h clock format.

Method type

type uses24HourClock = () => boolean;

Usage example

import { uses24HourClock } from "react-native-localize";

console.log(uses24HourClock());
// -> true

---

usesMetricSystem()

Returns true if the user prefers metric measure system, false if they prefer imperial.

Method type

type usesMetricSystem = () => boolean;

Usage example

import { usesMetricSystem } from "react-native-localize";

console.log(usesMetricSystem());
// -> true

---

usesAutoDateAndTime()

Tells if the automatic date & time setting is enabled on the phone. Android only

Method type

type usesAutoDateAndTime = () => boolean | undefined;

Usage example

import { usesAutoDateAndTime } from "react-native-localize";

console.log(usesAutoDateAndTime()); // true or false

---

usesAutoTimeZone()

Tells if the automatic time zone setting is enabled on the phone. Android only

Method type

type usesAutoTimeZone = () => boolean | undefined;

Usage example

import { usesAutoTimeZone } from "react-native-localize";

console.log(usesAutoTimeZone());

---

findBestLanguageTag()

Returns the best language tag possible and its reading direction. Useful to pick the best translation available.

[!NOTE]

It respects the user preferred languages list order (see explanations).

Method type

type findBestLanguageTag = (
  languageTags: string[],
) => { languageTag: string; isRTL: boolean } | void;

Usage example

import { findBestLanguageTag } from "react-native-localize";

console.log(findBestLanguageTag(["en-US", "en", "fr"]));
// -> { languageTag: "en-US", isRTL: false }

---

openAppLanguageSettings()

Opens the app language settings.

[!WARNING]

This feature is available only on Android 13+ and require configuring your app's supported locales.

Method type

type openAppLanguageSettings = () => Promise<void>;

Usage example

import { openAppLanguageSettings } from "react-native-localize";

openAppLanguageSettings("application").catch((error) => {
  console.warn("Cannot open app language settings", error);
});

Examples with @formatjs/intl

Browse the files in the /example directory.

How to update supported localizations (iOS)

You can add / remove supported localizations in your Xcode project infos:

How to test your code

Because it's a native module, you need to mock this package.
The package provides a default mock you may import in your __mocks__ directory:

// __mocks__/react-native-localize.ts
export * from "react-native-localize/mock"; // or "react-native-localize/mock/jest"

Sponsors

This module is provided as is, I work on it in my free time.

If you or your company uses it in a production app, consider sponsoring this project 💰. You also can contact me for premium enterprise support: help with issues, prioritize bugfixes, feature requests, etc.