translate method

String translate(String key, { String? keyPlural, List<Object>? pArgs, Map<String, Object>? nArgs, String? domain, String msgctxt = '', })

Returns the translation of a string

context.t('Hello world');

// You can also use named arguments:
context.t('Hello {name}', nArgs: {'name': 'world'});

// Or positional arguments:
context.t('Hello {0}', pArgs: ['world']);

// If you want to use plural forms, you can use the `keyPlural` argument:
context.t('One thing', keyPlural: 'Many things', nArgs: {'count': 2});
// or
context.t('One thing', keyPlural: 'Many things', pArgs: [2]);

@param key String to be translated @param keyPlural String to be translated when count is plural @param pArgs Positional arguments @param nArgs Named arguments @param domain A gettext domain name @param msgctxt Translation context @returns Translation or the original string if no translation was found

@throws ArgumentError if both pArgs and nArgs are provided @throws ArgumentError if keyPlural is provided but no count argument is provided

Implementation

String translate(
  String key, {
  String? keyPlural,
  List<Object>? pArgs,
  Map<String, Object>? nArgs,
  String? domain,
  String msgctxt = '',
}) {
  assert(
    pArgs == null || nArgs == null,
    'You can only use one of pArgs (position arguments) or nArgs (named arguments)',
  );
  late String message;

  if (keyPlural != null) {
    /// return pluralised translation
    final num? count = nArgs?.values.whereType<num?>().firstOrNull ?? pArgs?.whereType<num?>().firstOrNull;

    if (count == null) {
      throw ArgumentError('You must provide a count argument either as a named argument or as a positional argument');
    }

    message = _gt.ngettext(key, keyPlural, count.toInt(), domain: domain, msgctxt: msgctxt);
  } else {
    /// return singular translation
    message = _gt.gettext(key, domain: domain, msgctxt: msgctxt);
  }

  if (nArgs != null) {
    /// Replace named arguments
    for (final entry in nArgs.entries) {
      message = message.replaceAll('{${entry.key}}', entry.value.toString());
    }
  } else if (pArgs != null) {
    /// Replace positional arguments
    for (var i = 0; i < pArgs.length; i++) {
      message = message.replaceAll('{$i}', pArgs[i].toString());
    }
  }

  return message;
}