Offset & Delay Animation

offsetdelay.dart

//Stateful Widget created for this

  @override
  void initState() {
    super.initState();

    _controller =
        AnimationController(vsync: this, duration: Duration(seconds: 2));

    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,
        ));
        _lateAnimation = Tween(begin: 0.0, end: 1.0).animate(CurvedAnimation(
            parent: _controller,
            curve: Interval(
              0.2,
              1.0,
              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);

    _lateAnimation = Tween(begin: -1.0, end: 0.0).animate(CurvedAnimation(
        parent: _controller,
        curve: Interval(
          0.2,
          1.0,
          curve: Curves.fastOutSlowIn,
        )));
  }

  // Views to have this animations.