将Flutter的多行TextField滚动到end

在Flutter中，TextField控件默认情况下不支持自动滚动到内容的末尾。但是，你可以通过一些方法实现这个功能。以下是一个示例代码，展示了如何将多行TextField滚动到内容的末尾：

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('Scroll TextField to End')),
        body: ScrollableTextField(),
      ),
    );
  }
}

class ScrollableTextField extends StatefulWidget {
  @override
  _ScrollableTextFieldState createState() => _ScrollableTextFieldState();
}

class _ScrollableTextFieldState extends State<ScrollableTextField> {
  final TextEditingController _controller = TextEditingController();
  final ScrollController _scrollController = ScrollController();

  @override
  void initState() {
    super.initState();
    _controller.addListener(_scrollToEnd);
  }

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

  void _scrollToEnd() {
    _scrollController.animateTo(
      _scrollController.position.maxScrollExtent,
      duration: Duration(milliseconds: 200),
      curve: Curves.easeOut,
    );
  }

  @override
  Widget build(BuildContext context) {
    return SingleChildScrollView(
      controller: _scrollController,
      child: TextField(
        controller: _controller,
        maxLines: null, // 允许多行输入
        decoration: InputDecoration(
          hintText: 'Type something...',
        ),
      ),
    );
  }
}