Defining a Hinge Animation

hinge_animation_controller.dart

  AnimationController _controller;

  Animation _rotateAnimation;
  Animation<double> _slideAnimation;
  Animation<double> _opacityAnimation;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
    _controller = AnimationController(
      vsync: this,
      duration: Duration(milliseconds: 3000),
    );

    _rotateAnimation = Tween(end: 0.15, begin: 0.0)
        .animate(
      CurvedAnimation(
          parent: _controller,
          curve: Interval(0.0, 0.5, curve: Curves.bounceInOut),
      ),
    );

    _slideAnimation = Tween(begin: 100.0, end: 600.0).animate(
      CurvedAnimation(
        parent: _controller,
        curve: Interval(0.5, 1.0, curve: Curves.fastOutSlowIn),
      ),
    );

    _opacityAnimation = Tween(begin: 1.0, end: 0.0).animate(
      CurvedAnimation(
        parent: _controller,
        curve: Interval(0.5, 1.0, curve: Curves.fastOutSlowIn),
      ),
    );

  }