AnimationController createAnimationController({@required TickerProvider vsync })

Creates an animation controller useful for driving a snack bar's entrance and exit animation.

Source 

static AnimationController createAnimationController({ @required TickerProvider vsync }) {
  return new AnimationController(
    duration: _kSnackBarTransitionDuration,
    debugLabel: 'SnackBar',
    vsync: vsync,
  );
}