factory constructor Notification

Source

factory Notification(String title,
    {String dir: null,
    String body: null,
    String lang: null,
    String tag: null,
    String icon: null}) {
  var parsedOptions = {};
  if (dir != null) parsedOptions['dir'] = dir;
  if (body != null) parsedOptions['body'] = body;
  if (lang != null) parsedOptions['lang'] = lang;
  if (tag != null) parsedOptions['tag'] = tag;
  if (icon != null) parsedOptions['icon'] = icon;
  return Notification._factoryNotification(title, parsedOptions);
}