Check out example codes for "color from hex code flutter". It will help you in understanding the concepts better.

Code Example 1

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);

Learn ReactJs, React Native from akashmittal.com