setFormat method

Implementation

void setFormat() {
  if (format != null) return;
  if (type == "date" || type == "year" || type == "range") {
    format = 'y/M/d';
  } else if (type == "time") {
    format = 'H:m';
  } else {
    format = 'y/M/d H:mm';
  }
}