Easing Animation

easinganimation_step3.dart

    void handler(status) {
      if (status == AnimationStatus.completed) {
        _animation.removeStatusListener(handler);
        _controller.reset();
        _animation = Tween(begin: 0.0, end: 1.0).animate(CurvedAnimation(
          parent: _controller,
          curve: Curves.fastOutSlowIn,
        ))..addStatusListener((status){
          if (status == AnimationStatus.completed) {
            Navigator.pop(context);
          }
        });
        _controller.forward();
      }
    }

    _animation = Tween(begin: -1.0, end: 0.0).animate(CurvedAnimation(
      parent: _controller,
      curve: Curves.fastOutSlowIn,
    ))..addStatusListener(handler);