如何在flutter中使用lerp()方法?有哪些用例？

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Lerp Example')),
        body: Center(
          child: AnimatedContainer(
            duration: Duration(seconds: 2),
            width: lerpDouble(100, 300, _animation.value),
            height: lerpDouble(100, 300, _animation.value),
            color: Color.lerp(Colors.red, Colors.blue, _animation.value),
          ),
        ),
      ),
    );
  }

  AnimationController _animation;
  Animation<double> _animationValue;

  @override
  void initState() {
    super.initState();
    _animation = AnimationController(
      vsync: this,
      duration: Duration(seconds: 2),
    )..repeat();
    _animationValue = Tween<double>(begin: 0, end: 1).animate(_animation);
  }

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

Color color = Color.lerp(Colors.red, Colors.blue, 0.5); // 结果为紫色