initializeDateFormattingCustom function

void initializeDateFormattingCustom({ String? locale, DateSymbols? symbols, Map<String, String>? patterns, })

This should be called for at least one locale before any date formatting methods are called.

It sets up the lookup for date information. The symbols argument should contain a populated DateSymbols, and patterns should contain a Map for the same locale from skeletons to the specific format strings. For examples, see date_time_patterns.dart.

If data for this locale has already been initialized it will be overwritten.

Implementation

void initializeDateFormattingCustom({
  String? locale,
  DateSymbols? symbols,
  Map<String, String>? patterns,
}) {
  initializeDateSymbols(_emptySymbols);
  initializeDatePatterns(_emptyPatterns);
  if (symbols == null) {
    throw ArgumentError('Missing DateTime formatting symbols');
  }
  if (patterns == null) {
    throw ArgumentError('Missing DateTime formatting patterns');
  }
  if (locale != symbols.NAME) {
    throw ArgumentError.value([
      locale,
      symbols.NAME,
    ], 'Locale does not match symbols.NAME');
  }
  dateTimeSymbols[symbols.NAME] = symbols;
  dateTimePatterns[symbols.NAME] = patterns;
}