LocalHelper.kt

object LocaleHelper {

    private val SELECTED_LANGUAGE = "app_lang"

    fun onAttach(context: Context): Context {
        val langu = getPersistedData(context, Locale.getDefault().language)
        return setLocale(context, langu)
    }

    fun onAttach(context: Context, defaultLanguage: String): Context {
        val langu = getPersistedData(context, defaultLanguage)
        return setLocale(context, langu)
    }

    fun getLanguage(context: Context?): String? {
        return getPersistedData(context, Locale.getDefault().language)
    }

    fun setLocale(context: Context, language: String?): Context {
        persist(context, language)
        return updateResources(context, language)
    }


    fun getCurrentLocale(context: Context): Locale {
        return Locale(getLanguage(context) ?: Locale.getDefault().language)
    }

    private fun getPersistedData(context: Context?, defaultLanguage: String): String? {
        val preferences = PreferenceManager.getDefaultSharedPreferences(context)
        return preferences.getString(SELECTED_LANGUAGE, defaultLanguage)
    }

    private fun persist(context: Context, language: String?) {
        val preferences = PreferenceManager.getDefaultSharedPreferences(context)
        val editor = preferences.edit()

        editor.putString(SELECTED_LANGUAGE, language)
        editor.apply()
    }


    @TargetApi(Build.VERSION_CODES.N)
    private fun updateResources(context: Context, language: String?): Context {
        val locale = Locale(language)
        Locale.setDefault(locale)

        val configuration = context.resources.configuration
        configuration.setLocale(locale)
        configuration.setLayoutDirection(locale)

        return context.createConfigurationContext(configuration)
    }


}