react-language-context

Simple library to support multilingualism in react applications using react context.

Install

npm install --save react-language-context

Info

Library is using react context for keeping language information in application.

Get started

1. Install this package
2. See section LanguageProvider
3. See section LanguageConsumer
4. You should be able to use this library :)

Components

This library contains three components. LanguageProvider, LanguageConsumer and LanguageContext. Mostly you need to use LanguageProvider and LanguageConsumer for multilang support.

LanguageProvider

Component LanguageProvider should be placed in "app or top" component - component where you will keep language settings. State of the top component should be expanded with following - lang and defaultLang. This state property could be simply changed with setState function. It is up to you how you implement the language change.

PROPS	TYPE	INFO
lang	string	current language of application - "es"
defaultLang	string	default language of application - "en"
useDefaultLangInstead	bool	true default language is used when translation is missing for current language, false nothing is shown if translation is missing for current language

Example of usage

export  default  class  App  extends  Component {
 
 constructor(props) {
  super(props);
  this.state = { lang:  "es", defaultLang:  "en" };
  this._changeLang = this._changeLang.bind(this);
 }
 
 _changeLang(lang) {
  this.setState({ lang });
 }
 
 render() {
  return (
   <div>
    <LanguageProvider
     lang={this.state.lang}
     defaultLang={this.state.defaultLang}
     useDefaultLangInstead ={false}
     >
     //example components
     <Header/>
     <Body/>
     <Footer/>  
   </LanguageProvider>
  </div>);
 }
}

LanguageConsumer

Component LanguageConsumer is used as the shown text.

PROPS	TYPE	INFO
text	object	simple object with keys - values, where key is language and value is text itself
replacer	object	simple object with keys - values, where key is regex which you want to replace with value

Example of prop text

{
 en:"Hello world!",
 es:"Hola Mundo!",
 cs:"Ahoj světe!"
}

Example of prop replacer

{
 en:"Hello $1",
 es:"Hola $1",
 cs:"Ahoj $1"
}

Example of usage

const Texts = {
 header:{
  en:"Header in english",
  es:"Encabezado en español",
  cs:"Hlavička v češtině"
 },
 body:{
  en:"Body in english",
  es:"Contenido en español",
  cs:"Obsah v češtině"
 }
}
 
<h1>
<LanguageConsumer  text={Texts.header}  />
</h1>
 
<p>
<LanguageConsumer  text={Texts.body}  />
</p>
 
<h2>
<LanguageConsumer text={Texts.dynamicHeader}  replacer={{$1: this.state.name}}/>
</h2>

LanguageContext

LanguageContext is used in both components LanguageProvider and LanguageConsumer. Most of the time you don't need to use it directly. But sometimes you can have some specific situation. So you can use it as react context and from it you can get 'Consumer'. With this you are able to do pretty much everything. This should be used for components which require string and not component inside them. For example - <option> tag. In context you will find properties from Provider - lang, defaultLang, useDefaultLangInstead.

Example of usage

<select>
<LanguageContext.Consumer>
 {({ lang, defaultLang, useDefaultLangInstead }) =>
  Object.keys(Texts.select).map(key  => (
   <option  key={key}  value={key}>{Texts.select[key]}</option>
 ))}
</LanguageContext.Consumer>
</select>

Example

import  React, { Component } from  "react";
import { LanguageProvider, LanguageConsumer,LanguageContext } from  "react-language-context";
import { Texts } from  "./texts";
 
export  default  class  App  extends  Component {
 
 constructor(props) {
  super(props);
  this.state = { lang: "en", defaultLang: "en", name: "Jar Jar" };
  this._handleChange = this._handleChange.bind(this);
  this._handleChangeName = this._handleChangeName.bind(this);
 }
 
 _handleChange(event) {
  this.setState({ lang:  event.target.value });
 }
 
 _handleChangeName(event) {
  this.setState({ name: event.target.value });
 }
 
 render() {
  return (
  <div>
   <LanguageProvider
    lang={this.state.lang}
    defaultLang={this.state.defaultLang}
    >
    <select  value={this.state.lang}  onChange={this._handleChange}>
     <LanguageContext.Consumer>
      {({ lang }) =>
      Object.keys(Texts.select[lang]).map(key  => (
       <option  key={lang+key}  value={key}>{Texts.select[lang][key]}</option>
      ))}
     </LanguageContext.Consumer>
    </select>
    <h1>
     <LanguageConsumer  text={Texts.header}  />
    </h1>
    <label>
     Name: <input type="text" value={this.state.name} onChange={this._handleChangeName} />
    </label>
     <h2>
      <LanguageConsumer text={Texts.dynamicHeader}  replacer={{$1: this.state.name}}/>
     </h2>
    <p>
     <LanguageConsumer  text={Texts.body}  />
    </p>
   </LanguageProvider>
  </div>
  );
  }
}
 

FAQ

1. I see [object Object] instead of valid text -> please see section LanguageContext

Release notes

01.01.2020 - 1.0.0 - first release 04.01.2020 - 1.1.0 - adds props replacer for component LanguageConsumer. This prop is used for dynamic translations. See LanguageConsumer for more info.

License

MIT ©