toHex method
Get an Hexadecimal representation of this color
Implementation
String toHex() {
final i = toInt();
final rgb = (i & 0xffffff).toRadixString(16).padLeft(6, '0');
final a = ((i & 0xff000000) >> 24).toRadixString(16).padLeft(2, '0');
return '#$rgb$a';
}