flutter color hex

Color myColor = Color(0xff123456) 

// where 123456 is your hex color code and
// 0xff is the opacity value and can be changed.

Color c = const Color(0xFF42A5F5);
Color c = const Color.fromARGB(0xFF, 0x42, 0xA5, 0xF5);
Color c = const Color.fromARGB(255, 66, 165, 245);
Color c = const Color.fromRGBO(66, 165, 245, 1.0);

const color = const Color(0xffb74093); // Second `const` is optional in assignments.

Color myHexColor = Color(0xff123456) 

// her you notice I use the 0xff and that is opacity or transparency of the color 
// and you can also change these value .

Hex Opacity Values

100% — FF

95% — F2

90% — E6

85% — D9

80% — CC

75% — BF

70% — B3

65% — A6

60% — 99

55% — 8C

50% — 80

45% — 73

40% — 66

35% — 59

30% — 4D

25% — 40

20% — 33

15% — 26

10% — 1A

5% — 0D

0% — 00