darken method
Darken the shade of the color by the amount
.
amount
is a double between 0 and 1.
Based on: https://stackoverflow.com/a/60191441.
Implementation
Color darken(double amount) {
assert(amount >= 0 && amount <= 1);
final f = 1 - amount;
return Color.fromARGB(
alpha,
(red * f).round(),
(green * f).round(),
(blue * f).round(),
);
}