randomWord method
Implementation
String randomWord() {
final wordType = _pickOne(Dictionary.mixWeighting);
final types = [Dictionary.kanji, Dictionary.hiragana, Dictionary.katakana];
final type = types[wordType - 1];
final length = type['text']!.toList().length - 1;
final word = type['text']![_randomInteger(0, length)] as String;
return word;
}