withAnimation method
Creates a copy of this snack bar but with the animation replaced with the given animation.
If the original snack bar lacks a key, the newly created snack bar will use the given fallback key.
Implementation
SnackBar withAnimation(Animation<double> newAnimation, { Key fallbackKey }) {
return SnackBar(
key: key ?? fallbackKey,
content: content,
backgroundColor: backgroundColor,
action: action,
duration: duration,
animation: newAnimation,
);
}