如何在Flutter中添加TextEditingController并从动态TextFormField中获取文本值？

import 'package:flutter/material.dart';

TextEditingController _controller = TextEditingController();

TextFormField(
  controller: _controller,
  // 其他属性和回调函数
)

String textValue = _controller.text;

import 'package:flutter/material.dart';

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

class _MyWidgetState extends State<MyWidget> {
  TextEditingController _controller = TextEditingController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Column(
        children: [
          TextFormField(
            controller: _controller,
            decoration: InputDecoration(
              labelText: '输入文本',
            ),
          ),
          RaisedButton(
            onPressed: () {
              String textValue = _controller.text;
              print('获取到的文本值：$textValue');
            },
            child: Text('获取文本值'),
          ),
        ],
      ),
    );
  }
}