如何实现动画，比如在flutter中关闭电影字幕？

import 'package:flutter/material.dart';

class SubtitleAnimation extends StatefulWidget {
  @override
  _SubtitleAnimationState createState() => _SubtitleAnimationState();
}

class _SubtitleAnimationState extends State<SubtitleAnimation>
    with SingleTickerProviderStateMixin {
  AnimationController _animationController;
  Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _animationController = AnimationController(
      duration: Duration(milliseconds: 500),
      vsync: this,
    );

    _animation = Tween<double>(begin: 1.0, end: 0.0).animate(_animationController);

    _animationController.addStatusListener((status) {
      if (status == AnimationStatus.completed) {
        // 动画完成后执行操作，比如隐藏字幕部件
        setState(() {
          // 隐藏字幕部件的操作
        });
      }
    });

    // 启动动画
    _animationController.forward();
  }

  @override
  void dispose() {
    _animationController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Opacity(
          opacity: _animation.value,
          child: child,
        );
      },
      child: SubtitleWidget(), // 替换为你的字幕部件
    );
  }
}

class SubtitleWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Text(
      '电影字幕',
      style: TextStyle(fontSize: 16.0),
    );
  }
}