下面是数字键盘的代码: keyboardType: TextInputType。当你在文本框中添加这个代码时，它将打开数字键盘。

  final _mobileFocus = new FocusNode();
  final _mobile = TextEditingController();


     TextFormField(
          controller: _mobile,
          focusNode: _mobileFocus,
          maxLength: 10,
          keyboardType: TextInputType.phone,
          decoration: new InputDecoration(
            counterText: "",
            counterStyle: TextStyle(fontSize: 0),
            hintText: "Mobile",
            border: InputBorder.none,
            hintStyle: TextStyle(
              color: Colors.black,
                fontSize: 15.0.
            ),
          ),
          style: new TextStyle(
              color: Colors.black,
              fontSize: 15.0,
           ),
          );

你可以添加键盘类型的输入格式，就像这样

TextField(
    inputFormatters: <TextInputFormatter>[
      FilteringTextInputFormatter.digitsOnly
    ],// Only numbers can be entered
    keyboardType: TextInputType.number,
   );

下面是Android上实际的手机键盘代码:

按键部分:keyboardType: TextInputType.phone，

  TextFormField(
    style: TextStyle(
      fontSize: 24
    ),
    controller: _phoneNumberController,
    keyboardType: TextInputType.phone,
    decoration: InputDecoration(
      prefixText: "+1 ",
      labelText: 'Phone number'),
    validator: (String value) {
      if (value.isEmpty) {
        return 'Phone number (+x xxx-xxx-xxxx)';
      }
      return null;
    },
  ),

你可以指定数字为keyboardType的TextField使用:

keyboardType: TextInputType.number

检查一下我的总管。飞镖文件

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

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return new MaterialApp(
      home: new HomePage(),
      theme: new ThemeData(primarySwatch: Colors.blue),
    );
  }
}

class HomePage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return new HomePageState();
  }
}

class HomePageState extends State<HomePage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      backgroundColor: Colors.white,
      body: new Container(
          padding: const EdgeInsets.all(40.0),
          child: new Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          new TextField(
            decoration: new InputDecoration(labelText: "Enter your number"),
            keyboardType: TextInputType.number,
            inputFormatters: <TextInputFormatter>[
    FilteringTextInputFormatter.digitsOnly
], // Only numbers can be entered
          ),
        ],
      )),
    );
  }
}

你可以试试这个:

TextFormField(
     keyboardType: TextInputType.number,
     decoration: InputDecoration(
              prefixIcon: Text("Enter your number: ")
     ),
     initialValue: "5",
     onSaved: (input) => _value = num.tryParse(input),
),

对于那些正在寻找使TextField或TextFormField只接受数字作为输入的人，尝试以下代码块:

用于flutter 1.20或更新版本

TextFormField(
  controller: _controller,
  keyboardType: TextInputType.number,
  inputFormatters: <TextInputFormatter>[
   // for below version 2 use this
 FilteringTextInputFormatter.allow(RegExp(r'[0-9]')), 
// for version 2 and greater youcan also use this
 FilteringTextInputFormatter.digitsOnly

  ],
  decoration: InputDecoration(
    labelText: "whatever you want",
    hintText: "whatever you want",
    icon: Icon(Icons.phone_iphone)
  )
)

对于1.20的早期版本

TextFormField(
    controller: _controller,
    keyboardType: TextInputType.number,
    inputFormatters: <TextInputFormatter>[
        WhitelistingTextInputFormatter.digitsOnly
    ],
    decoration: InputDecoration(
        labelText:"whatever you want", 
        hintText: "whatever you want",
        icon: Icon(Icons.phone_iphone)
    )
)