Flutter TextField仅输入十进制数

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Decimal TextField'),
        ),
        body: Center(
          child: Padding(
            padding: EdgeInsets.all(16.0),
            child: TextField(
              keyboardType: TextInputType.numberWithOptions(decimal: true),
              inputFormatters: [
                WhitelistingTextInputFormatter(RegExp(r'^\d+\.?\d{0,2}')),
              ],
              decoration: InputDecoration(
                labelText: 'Enter a decimal number',
              ),
            ),
          ),
        ),
      ),
    );
  }
}