flutter - TextFormField的后缀图标问题

Question

我有一个带后缀图标的TextFormField，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:

(另外文字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

所以，我尝试使用提到的 IntrinsicHeight 小部件:

IntrinsicHeight(
  child: TextFormField(...)
)

确实，它标准化了我的 TextFormField 的高度，但现在有了自动换行/换行符:

如您所见，多线调整不再正常工作，几乎无法确定何时展开。

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

Answer 1

您可以在下面复制粘贴运行完整代码
第 1 步:您可以使用 suffixIconConstraints 来减少填充 https://github.com/flutter/flutter/pull/50058
第二步:使用InkWell包裹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),
      ),
    );
  }
}