详解React-Native全球化多语言切换工具库react-native-i18n

export default {
 home: {
  greeting: 'Greeting in en',
  tab_home: 'Home',
  tab_donate: 'Donate',
  tab_demo: 'Demo',
  language: 'language',
  live_demo: 'Live Demo',
  buy_me_coffee: 'Buy me a coffee',
  gitee: 'Gitee',
  star_me: 'Star me',
  donate: 'donate',
  exit: 'exit?',
 },
 donate: {
  donate: 'donate us~~~',
  donate_desc: '© 2017 Pactera Technology International Limited. All rights reserved.',
 },
 demo: {
  dialog: 'dialog',
  button: 'button',
  switch: 'switch',
  action_sheet: 'Action Sheet',
 }
};

export default {
 home: {
  greeting: 'Greeting in zh',
  tab_home: '首页',
  tab_donate: '捐赠',
  tab_demo: '例子',
  language: '语言',
  live_demo: '例子',
  buy_me_coffee: '请我一杯coffee',
  gitee: 'Gitee',
  star_me: '关注我',
  donate: '贡献',
  exit: '是否退出?',
 },
 donate: {
  donate: '支持我们～~',
  donate_desc: '© 2017 Pactera Technology International Limited. All rights reserved.',
 },
 demo: {
  dialog: '提示框',
  button: '按钮',
  switch: '开关',
  action_sheet: '',
 }
};

import i18n from 'react-native-i18n';
import en from './en';
import zh from './zh';

i18n.defaultLocale = 'en';
i18n.fallbacks = true;
i18n.translations = {
 en,
 zh,
};

export {i18n};

 ToastAndroid.show(i18n.t('home.exit'),ToastAndroid.SHORT);

public class RNI18nModule extends ReactContextBaseJavaModule {

 public RNI18nModule(ReactApplicationContext reactContext) {
 super(reactContext);
 }
 //RN调用的控件名
 @Override
 public String getName() {
 return "RNI18n";
 }

 //对取出的Locale列表进行格式化的方法
 private String toLanguageTag(Locale locale) {
 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
  return locale.toLanguageTag();
 }

 StringBuilder builder = new StringBuilder();
 builder.append(locale.getLanguage());

 if (locale.getCountry() != null) {
  builder.append("-");
  builder.append(locale.getCountry());
 }

 return builder.toString();
 }

 private WritableArray getLocaleList() {
 WritableArray array = Arguments.createArray();

 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
  //获取区域设置列表。这是获取区域的首选方法。
  LocaleList locales = getReactApplicationContext()
   .getResources().getConfiguration().getLocales();

  for (int i = 0; i < locales.size(); i++) {
  array.pushString(this.toLanguageTag(locales.get(i)));
  }
 } else {
  array.pushString(this.toLanguageTag(getReactApplicationContext()
   .getResources().getConfiguration().locale));
 }

 return array;
 }

 //js端可获取属性的列表
 @Override
 public Map<String, Object> getConstants() {
 HashMap<String, Object> constants = new HashMap<String,Object>();
 constants.put("languages", this.getLocaleList());
 return constants;
 }

 //提供给js端调用的方法，用来获取默认的语言环境，回调方式用的是promise
 @ReactMethod
 public void getLanguages(Promise promise) {
 try {
  promise.resolve(this.getLocaleList());
 } catch (Exception e) {
  promise.reject(e);
 }
 }
}