Defining the Bounce Animation

bounce_animation_controller.dart

  AnimationController _controller;
  Animation<double> _slideAnimation;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
    _controller = AnimationController(
      vsync: this,
      duration: Duration(milliseconds: 1000),
    );

    _slideAnimation = Tween(begin: 200.0, end: 120.0).animate(
      CurvedAnimation(
        parent: _controller,
        curve: Interval(0.0, 1.0, curve: Curves.elasticIn),
      ),
    )..addStatusListener((AnimationStatus status) {
      if (status == AnimationStatus.completed) {
        _controller.repeat(reverse: true);
      }
    });
  }