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我试图显示一个覆盖的宽度相同的文本字段。下面的代码示例工作正常，但当我在浏览器中运行它并调整窗口大小时，文本字段会调整大小，但覆盖层仍保留旧的尺寸。
如何在调整窗口大小时更新（而不是重新渲染）覆盖的尺寸？
下面是我尝试过的示例代码

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);
  final String title;
  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final ScrollController _scrollController = ScrollController();

  Widget _list() {
    return Container(
      height: 5 * 40,
      child: Scrollbar(
          controller: _scrollController,
          thumbVisibility: true,
          child: ListView.builder(
              controller: _scrollController,
              padding: EdgeInsets.zero,
              itemCount: 20,
              itemBuilder: (context, index) => ListTile(
                    title: Text('item $index'),
                    onTap: () {
                      _overlayEntry.remove();
                    },
                  ))),
    );
  }

  final LayerLink _layerLink = LayerLink();

  OverlayEntry _createOverlay() {
    final renderBox = context.findRenderObject() as RenderBox;
    final size = renderBox.size;
    final offset = renderBox.localToGlobal(Offset.zero);
    return OverlayEntry(
        builder: (context) => Positioned(
              left: offset.dx,
              width: size.width,
              child: CompositedTransformFollower(
                  offset: Offset(0, 50),
                  link: _layerLink,
                  child: Material(color: Colors.red, child: _list())),
            ));
  }

  late OverlayEntry _overlayEntry;

  @override
  void initState() {
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _overlayEntry = _createOverlay();
    });
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            CompositedTransformTarget(
              link: _layerLink,
              child: TextFormField(
                decoration: InputDecoration(
                  focusedBorder: OutlineInputBorder(
                    borderSide: BorderSide(
                      color: Colors.black.withOpacity(0.8),
                    ),
                  ),
                  border: OutlineInputBorder(
                    borderSide: BorderSide(color: Colors.red),
                  ),
                ),
                onTap: () {
                   if (_overlayEntry.mounted) {
                        _overlayEntry.remove();
                   }
                   Overlay.of(context).insert(_overlayEntry);
                },
                onChanged: (query) {},
              ),
            ),
          ],
        ),
      ),
    );
  }
}

下面是上述代码的输出

• 请注意，覆盖尺寸与窗口大小不匹配（调整窗口大小时）*

我们可以通过调整Positioned.right参数来强制叠加尺寸

OverlayEntry(
        builder: (context) => Positioned(
              left: 0,
              right: 0, // custom offset from right
              // width: textFieldSize.width,
              child: CompositedTransformFollower(
                  offset: Offset(0, 50),
                  link: _layerLink,
                  child: Material(color: Colors.red, child: _list())),
            ));

但是如果我们在Textfield周围给予填充，例如，如果我设置Positioned.right:0并在Textfield周围提供填充，则覆盖层将始终占据整个宽度，这将失败。

我尝试的最后一个解决方案是将文本字段的宽度设置为覆盖宽度，但我不确定如何更新文本字段渲染框，以便覆盖占用预期的尺寸。

OverlayEntry _createOverlay() {
    /// textfield dimensions
    final textFieldRenderBox =
        textFieldKey.currentContext!.findRenderObject() as RenderBox;
    final textFieldOffset = textFieldRenderBox.localToGlobal(Offset.zero);
    final textFieldSize = textFieldRenderBox.size;
    print('$textFieldSize $textFieldOffset ');
    return OverlayEntry(
        builder: (context) => Positioned(
              left: 0,
              width: textFieldSize.width,
              child: CompositedTransformFollower(
                  offset: Offset(0, 50),
                  link: _layerLink,
                  child: Material(color: Colors.red, child: _list())),
            ));
  }

编辑：我尝试使用didChangeMetrics监听MediaQueyChanges并使用ValueListenableBuilder更新Overlay，但它的janky和更新延迟如下输出和代码