Flutter/キャスト

色と文字列

参考：https://stackoverflow.com/questions/49835146/how-to-convert-flutter-color-to-string-and-back-to-a-color

Color color = new Color(0x12345678);
String colorString = color.toString(); // Color(0x12345678)
String valueString = colorString.split('(0x')[1].split(')')[0]; // 12345678
int value = int.parse(valueString, radix: 16);
Color otherColor = new Color(value);