Função para obter as letras inicias do nome e sobrenome

two_letters.dart

void main() {
  var name = 'Lucivaldo Castro Castelo Branco';
  print(twoLetters(name));
}

String twoLetters(String name) {
  if (name.trim().isEmpty) return null;

  var nameSplited = name.trim().replaceAll(RegExp(r'\s+', ), ' ').split(' ');
  var letters = nameSplited.first[0];
  
  if (nameSplited.length > 1) {
    letters = nameSplited.sublist(0, 2).reduce((value, element) {
      return value[0] + element[0];
    });
  }

  return letters;
}