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 new ArgumentError("Missing DateTime formatting symbols");
  if (patterns == null)
    throw new ArgumentError("Missing DateTime formatting patterns");
  if (locale != symbols.NAME)
    throw new ArgumentError.value(
        [locale, symbols.NAME], "Locale does not match symbols.NAME");
  dateTimeSymbols[symbols.NAME] = symbols;
  dateTimePatterns[symbols.NAME] = patterns;
}