int.parse(specificStringsYouWantToParse, radix: sizeOfRadix); // Use this

//Implementation
void main() {
  final fullString = fullStringYouWantToParseFrom;

  for (int i = 0; i <= fullString.length - 8; i += 8) {
    final hex = fullString.substring(i, i + 8);

    final number = int.parse(hex, radix: sizeOfRadix);
    print(number);
  }