如何在Flutter中更改ColorTween颜色

import 'package:flutter/material.dart';

AnimationController _controller = AnimationController(
  duration: Duration(seconds: 1), // 动画持续时间为1秒
  vsync: this, // 传入当前Widget的State对象作为TickerProvider
);

ColorTween _colorTween = ColorTween(
  begin: Colors.red, // 起始颜色为红色
  end: Colors.blue, // 结束颜色为蓝色
);

Color _currentColor = _colorTween.lerp(_controller.value);

Container(
  color: _currentColor,
  // 其他Widget内容
)

_controller.forward();

import 'package:flutter/material.dart';

class MyWidget extends StatefulWidget {
  @override
  _MyWidgetState createState() => _MyWidgetState();
}

class _MyWidgetState extends State<MyWidget> with TickerProviderStateMixin {
  AnimationController _controller;
  ColorTween _colorTween;
  Color _currentColor;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: Duration(seconds: 1),
      vsync: this,
    );
    _colorTween = ColorTween(
      begin: Colors.red,
      end: Colors.blue,
    );
    _currentColor = _colorTween.lerp(_controller.value);
  }

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

  @override
  Widget build(BuildContext context) {
    return Container(
      color: _currentColor,
      // 其他Widget内容
    );
  }

  void startAnimation() {
    _controller.forward();
  }
}