toHex method
Implementation
String toHex({bool leadingHashSign = true}) {
return '${leadingHashSign ? '#' : ''}'
'${alphaChannel.toRadixString(16).padLeft(2, '0')}'
'${redChannel.toRadixString(16).padLeft(2, '0')}'
'${greenChannel.toRadixString(16).padLeft(2, '0')}'
'${blueChannel.toRadixString(16).padLeft(2, '0')}';
}