addOpacity method
Makes the current color more transparent, by the given value
,
from 0
(total transparency) to 1
(no change).
If value
is not provided, it will be 0.5 (50% change).
If value
is less than 0, it's 0. If more than 1, it's 1.
Makes it more transparent if percent < 1.
Implementation
Color addOpacity([double value = 0.5]) =>
Color.fromARGB((alpha * _limit(value)).round(), red, green, blue);