TextFormField 后缀图标的问题

Question

我有一个TextFormField带后缀的图标，用作IconButton：

TextFormField(
  autocorrect: false,
  decoration: InputDecoration(
    prefixIcon: widget.icon,
    isDense: true,
    suffixIcon: IconButton(
      icon: Icon(Icons.clear),
      onPressed: () {...}                 
    )
  ),     
  controller: _controller,
  maxLines: null,
)

我的问题是，后缀图标增加了文本字段的高度：

（此外，文本末尾和图标之间的空间太大）：

我尝试了不同的方法来避免这种情况，但几乎一切都失败了。最后我在这里找到了一个可能的解决方案：https://github.com/flutter/flutter/issues/21908#issuecomment-516434465

因此，我尝试使用IntrinsicHeight提到的小部件：

IntrinsicHeight(
  child: TextFormField(...)
)

事实上，它标准化了 my 的高度TextFormField，但现在有一些带有自动换行/换行符的东西：

正如您所看到的，多线调整不再正常工作，几乎不确定何时会扩展。

那么：您知道如何解决我最初的后缀图标和生成的文本字段高度问题吗？或者您现在如何解决使用时的多行问题IntrisicHeight？

Answer 1

您可以在下面复制粘贴运行完整代码
步骤 1：您可以使用suffixIconConstraints减少填充https://github.com/flutter/flutter/pull/50058
步骤 2：使用InkWell换行Icon并设置Icon大小

TextFormField(
                autocorrect: false,
                decoration: InputDecoration(
                    prefixIcon: Icon(Icons.add),
                    prefixIconConstraints: BoxConstraints(
                      minWidth: 5,
                      minHeight: 5,
                    ),
                    isDense: true,
                    suffixIconConstraints: BoxConstraints(
                      minWidth: 2,
                      minHeight: 2,
                    ),
                    suffixIcon: InkWell(
                        child: Icon(Icons.clear, size: 14), onTap: () {})),
                controller: _controller1,
                maxLines: null,
              ),

工作演示

完整代码

import 'package:flutter/material.dart';

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

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

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  TextEditingController myController1 = TextEditingController();
  TextEditingController _controller1 = TextEditingController();
  TextEditingController _controller2 = TextEditingController();

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Expanded(
              child: TextFormField(
                autocorrect: false,
                decoration: InputDecoration(
                    prefixIcon: Icon(Icons.add),
                    prefixIconConstraints: BoxConstraints(
                      minWidth: 5,
                      minHeight: 5,
                    ),
                    isDense: true,
                    suffixIconConstraints: BoxConstraints(
                      minWidth: 2,
                      minHeight: 2,
                    ),
                    suffixIcon: InkWell(
                        child: Icon(Icons.clear, size: 14), onTap: () {})),
                controller: _controller1,
                maxLines: null,
              ),
            ),
            Expanded(
              child: TextFormField(
                autocorrect: false,
                decoration: InputDecoration(
                    prefixIcon: Icon(Icons.add),
                    prefixIconConstraints: BoxConstraints(
                      minWidth: 5,
                      minHeight: 5,
                    ),
                    isDense: true,
                    suffixIconConstraints: BoxConstraints(
                      minWidth: 2,
                      minHeight: 2,
                    ),
                    suffixIcon: InkWell(
                        child: Icon(Icons.clear, size: 14), onTap: () {})),
                controller: _controller2,
                maxLines: null,
              ),
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}