reverse method
Implementation
Future<void> reverse() async {
final tween = Tween<double>(
begin: 0,
end: _controller.value,
);
_animation = _controller
.drive(
CurveTween(
curve: Interval(
tween.begin!,
tween.end!,
curve: reverseCurve,
),
),
)
.drive(tween);
await _controller.reverse();
_animation = _controller;
}