How to create number input field in Flutter?

Question

I'm unable to find a way to create an input field in Flutter that would open up a numeric keyboard and should take numeric input only. Is this possible with Flutter material widgets? Some GitHub discussions seem to indicate this is a supported feature but I'm unable to find any documentation about it.

Answer 1

You can specify the number as keyboardType for the TextField using:

keyboardType: TextInputType.number

Check my main.dart file

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
            ),
          ],
        ),
      ),
    );
  }
}

Answer 2

For those who are looking for making TextField or TextFormField accept only numbers as input, try this code block :

for flutter 1.20 or newer versions

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)
  )
)

for earlier versions of 1.20

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)
    )
)

Note: You need to import services.dart when using FilteringTextInputFormatter

import 'package:flutter/services.dart';

Answer 3

Through this option you can strictly restricted another char with out number.

 inputFormatters: [WhitelistingTextInputFormatter.digitsOnly],
 keyboardType: TextInputType.number,

For using above option you have to import this

import 'package:flutter/services.dart';

using this kind of option user can not paste char in a textfield

Answer 4

Set the keyboard and a validator

String numberValidator(String value) {
  if(value == null) {
    return null;
  }
  final n = num.tryParse(value);
  if(n == null) {
    return '"$value" is not a valid number';
  }
  return null;
}

new TextFormField(
    keyboardType: TextInputType.number, 
    validator: numberValidator, 
    textAlign: TextAlign.right
    ...

• https://docs.flutter.io/flutter/material/TextFormField/TextFormField.html
• https://docs.flutter.io/flutter/services/TextInputType-class.html

Answer 5

To avoid paste not digit value, add after

keyboardType: TextInputType.number

this code :

inputFormatters: [FilteringTextInputFormatter.digitsOnly] 

from https://api.flutter.dev/flutter/services/FilteringTextInputFormatter-class.html

Answer 6

If you need to use a double number:

keyboardType: TextInputType.numberWithOptions(decimal: true),
inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.,]')),],
onChanged: (value) => doubleVar = double.parse(value),

RegExp('[0-9.,]') allows for digits between 0 and 9, also comma and dot.

RegExp('[0-9.,-]') allows for digits between 0 and 9, also comma, dot and minus sign (for negative numbers).

double.parse() converts from string to double.

Don't forget you need: import 'package:flutter/services.dart';

You can check and test a full demo at this dartpad

If you want to allow minus sign only at the start of the string:

final RegExp _myPattern = RegExp(r'^-?[\d,.]*$');
(...)
TextInputFormatter.withFunction(
  (TextEditingValue oldValue, TextEditingValue newValue) {
    return _myPattern.hasMatch(newValue.text)
        ? newValue
         : oldValue;
   },
 ),

You can check and test the full demo2 at this other dartpad

Answer 7

For those who need to work with money format in the text fields:

To use only: , (comma) and . (period)

and block the symbol: - (hyphen, minus or dash)

as well as the: ⌴ (blank space)

In your TextField, just set the following code:

keyboardType: TextInputType.numberWithOptions(decimal: true),
inputFormatters: [BlacklistingTextInputFormatter(new RegExp('[\\-|\\ ]'))],

The simbols hyphen and space will still appear in the keyboard, but will become blocked.

Answer 8

The TextField widget is required to set keyboardType: TextInputType.number, and inputFormatters: <TextInputFormatter>[FilteringTextInputFormatter.digitsOnly] to accept numbers only as input.

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

Example in DartPad

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

    void main() => runApp(new MyApp());
    
    class MyApp extends StatelessWidget {
      @override
      Widget build(BuildContext context) {
        return MaterialApp(
          home: HomePage(),
          theme: ThemeData(primarySwatch: Colors.blue),
        );
      }
    }
    
    class HomePage extends StatefulWidget {
      @override
      State<StatefulWidget> createState() {
        return HomePageState();
      }
    }
    
    class HomePageState extends State<HomePage> {
      @override
      Widget build(BuildContext context) {
        return Scaffold(
          backgroundColor: Colors.white,
          body: Container(
              padding: const EdgeInsets.all(40.0),
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  Text("This Input accepts Numbers only"),
                  SizedBox(height: 20),
                  TextField(
                    decoration: InputDecoration(
                      focusedBorder: OutlineInputBorder(
                        borderSide:
                            BorderSide(color: Colors.greenAccent, width: 5.0),
                      ),
                      enabledBorder: OutlineInputBorder(
                        borderSide: BorderSide(color: Colors.red, width: 5.0),
                      ),
                      hintText: 'Mobile Number',
                    ),
                    keyboardType: TextInputType.number,
                    inputFormatters: <TextInputFormatter>[
                      FilteringTextInputFormatter.digitsOnly
                    ], // Only numbers can be entered
                  ),
                  SizedBox(height: 20),
                  Text("You can test be Typing"),
                ],
              )),
        );
      }
    }

Answer 9

You can use this two attributes together with TextFormField

 TextFormField(
         keyboardType: TextInputType.number
         inputFormatters: [WhitelistingTextInputFormatter.digitsOnly],

It's allow to put only numbers, no thing else ..

https://api.flutter.dev/flutter/services/TextInputFormatter-class.html

Answer 10

As the accepted answer states, specifying keyboardType triggers a numeric keyboard:

keyboardType: TextInputType.number

Other good answers have pointed out that a simple regex-based formatter can be used to allow only whole numbers to be typed:

inputFormatters: [
  FilteringTextInputFormatter.allow(RegExp(r'[0-9]')),
],

The problem with this is that the regex only matches one symbol at a time, so limiting the number of decimal points (e.g.) cannot be achieved this way.

Also, others have also shown that if one wants validation for a decimal number, it can be achieved by using a TextFormField and it's validator parameter:

new TextFormField(
    keyboardType: TextInputType.number, 
    validator: (v) => num.tryParse(v) == null ? "invalid number" : null, 
    ...

The problem with this is that it cannot be achieved interactively, but only at form submission time.

---

I wanted to allow only decimal numbers to be typed, rather than validated later. My solution is to write a custom formatter leveraging int.tryParse:

/// Allows only decimal numbers to be input.
class DecimalNumberFormatter extends TextInputFormatter {
  @override
  TextEditingValue formatEditUpdate(
      TextEditingValue oldValue, TextEditingValue newValue) {
    // Allow empty input and delegate formatting decision to `num.tryParse`.
    return newValue.text != '' && num.tryParse(newValue.text) == null
        ? oldValue
        : newValue;
  }
}

Alternatively, one can use a regex for the custom formatter, which would apply to the whole input, not just a single symbol:

/// Allows only decimal numbers to be input. Limits decimal plates to 3.
class DecimalNumberFormatter extends TextInputFormatter {
  @override
  TextEditingValue formatEditUpdate(
      TextEditingValue oldValue, TextEditingValue newValue) {
    // Allow empty input.
    if (newValue.text == '') return newValue;

    // Regex: can start with zero or more digits, maybe followed by a decimal
    // point, followed by zero, one, two, or three digits.
    return RegExp('^\\d*\\.?\\d?\\d?\\d?\$').hasMatch(newValue.text)
        ? newValue
        : oldValue;
  }
}

This way, I can also limit the number of decimal plates to 3.

Answer 11

To Create number input field, You just need to give following property inside your textfield or textformfield.

TextField(
  keyboardType: TextInputType.number, // Set the keyboard type to number
  decoration: InputDecoration(
    hintText: 'Enter a number',
  ),
);

Answer 12

Here is code for actual Phone keyboard on Android:

Key part: 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;
    },
  ),

Answer 13

Number type only

keyboardType: TextInputType.number

And more option with number pad

keyboardType: TextInputType.numberWithOptions(decimal: true,signed: false)

Answer 14

Just add this to your TextFormField

  keyboardType: TextInputType.number,
  inputFormatters: <TextInputFormatter>[
  FilteringTextInputFormatter.allow(RegExp(r'[0-9]')), ],

Example,

TextFormField(
        controller: textController,
        onChanged: (value) {
         print(value);
        },
        keyboardType: TextInputType.number,
        inputFormatters: <TextInputFormatter>[
          FilteringTextInputFormatter.allow(RegExp(r'[0-9]')),
        ],
      ),

Answer 15

You can Easily change the Input Type using the keyboardType Parameter and you have a lot of possibilities check the documentation TextInputType so you can use the number or phone value

 new TextField(keyboardType: TextInputType.number)

Answer 16

You can try this:

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

Answer 17

keyboardType: TextInputType.number would open a num pad on focus, I would clear the text field when the user enters/past anything else.

keyboardType: TextInputType.number,
onChanged: (String newVal) {
    if(!isNumber(newVal)) {
        editingController.clear();
    }
}

// Function to validate the number
bool isNumber(String value) {
    if(value == null) {
        return true;
    }
    final n = num.tryParse(value);
    return n!= null;
}

Answer 18

For number input or numeric keyboard you can use keyboardType: TextInputType.number

TextFormField(
  decoration: InputDecoration(labelText:'Amount'),
    controller: TextEditingController(
  ),
  validator: (value) {
    if (value.isEmpty) {
      return 'Enter Amount';
    }
  },
  keyboardType: TextInputType.number
)

Answer 19

You can add input format with keyboard type, like this

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

Answer 20

I need en IntegerFormField with a controll of min/max. And the big problem is that OnEditingComlete is not called when the focus changes. Here is my solution:

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

class IntegerFormField extends StatefulWidget {
  final int value, min, max;
  final InputDecoration decoration;
  final ValueChanged<TextEditingController> onEditingComplete;
  IntegerFormField({@required this.value, InputDecoration decoration, onEditingComplete, int min, int max})
      : min = min ?? 0,
        max = max ?? maxIntValue,
        onEditingComplete = onEditingComplete ?? ((_) {}),
        decoration = decoration ?? InputDecoration()
  ;

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

class _State extends State<IntegerFormField> {
  final TextEditingController controller = TextEditingController();

  @override
  void initState() {
    super.initState();
    controller.text = widget.value.toString();
  }

  @override
  void dispose() {
    super.dispose();
  }

  void onEditingComplete() {
    {
      try {
        if (int.parse(controller.text) < widget.min)
          controller.text = widget.min.toString();
        else if (int.parse(controller.text) > widget.max)
          controller.text = widget.max.toString();
        else
          FocusScope.of(context).unfocus();
      } catch (e) {
        controller.text = widget.value.toString();
      }
      widget.onEditingComplete(controller);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Focus(
      child: TextFormField(
        controller: controller,
        inputFormatters: [FilteringTextInputFormatter.digitsOnly],
        keyboardType: TextInputType.number,
        decoration: widget.decoration,
      ),
      onFocusChange: (value) {
        if (value)
          controller.selection = TextSelection(baseOffset: 0, extentOffset: controller.value.text.length);
        else
          onEditingComplete();
      },
    );
  }
}

Answer 21

Set your keyboardType to TextInputType.number,

Eg: keyboardType: TextInputType.number,

         TextFormField(
            controller: yourcontroller,
            keyboardType: TextInputType.number,
            decoration: const InputDecoration(
              labelText: 'Mobile',
              suffixIcon: Padding(
                padding: EdgeInsets.only(),
                child:
                Icon(Icons.phone_outlined, color: Color(0xffff4876)),
              ),
            ),
            validator: (text) {
              if (text == null || text.isEmpty) {
                return 'Please enter your Mobile No.';
              }
              return null;
            },
          ),

Answer 22

U can Install package intl_phone_number_input

dependencies:
  intl_phone_number_input: ^0.5.2+2

and try this code:

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    var darkTheme = ThemeData.dark().copyWith(primaryColor: Colors.blue);

    return MaterialApp(
      title: 'Demo',
      themeMode: ThemeMode.dark,
      darkTheme: darkTheme,
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: Scaffold(
        appBar: AppBar(title: Text('Demo')),
        body: MyHomePage(),
      ),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final GlobalKey<FormState> formKey = GlobalKey<FormState>();

  final TextEditingController controller = TextEditingController();
  String initialCountry = 'NG';
  PhoneNumber number = PhoneNumber(isoCode: 'NG');

  @override
  Widget build(BuildContext context) {
    return Form(
      key: formKey,
      child: Container(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            InternationalPhoneNumberInput(
              onInputChanged: (PhoneNumber number) {
                print(number.phoneNumber);
              },
              onInputValidated: (bool value) {
                print(value);
              },
              selectorConfig: SelectorConfig(
                selectorType: PhoneInputSelectorType.BOTTOM_SHEET,
                backgroundColor: Colors.black,
              ),
              ignoreBlank: false,
              autoValidateMode: AutovalidateMode.disabled,
              selectorTextStyle: TextStyle(color: Colors.black),
              initialValue: number,
              textFieldController: controller,
              inputBorder: OutlineInputBorder(),
            ),
            RaisedButton(
              onPressed: () {
                formKey.currentState.validate();
              },
              child: Text('Validate'),
            ),
            RaisedButton(
              onPressed: () {
                getPhoneNumber('+15417543010');
              },
              child: Text('Update'),
            ),
          ],
        ),
      ),
    );
  }

  void getPhoneNumber(String phoneNumber) async {
    PhoneNumber number =
        await PhoneNumber.getRegionInfoFromPhoneNumber(phoneNumber, 'US');

    setState(() {
      this.number = number;
    });
  }

  @override
  void dispose() {
    controller?.dispose();
    super.dispose();
  }
}

Answer 23

Here is code for numeric keyboard : keyboardType: TextInputType.phone When you add this code in textfield it will open numeric keyboard.

  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,
           ),
          );

Answer 24

Here is code for actual Phone keyboard in Flutter:

     //Mobile
            const TextField(
              keyboardType: TextInputType.number,
              decoration: InputDecoration(
                  prefixIcon: Icon(Icons.phone), hintText: 'Mobile'),
            ),

Answer 25

For anyone who wants to allow phone number that starts with + (plus) sign. Try this

TextFormField(
  controller: controller,
  /// Add this
  keyboardType: TextInputType.numberWithOptions(decimal: true, signed: true),
  inputFormatters: [FilteringTextInputFormatter.allow(RegExp(r'^\+?\d*'))],
  ///
),

Answer 26

Here are all details on how to add numeric keybord, How to do validations, How to add stylings, and other stuff in dart/flutter. I hope it can help you to learn in a better way.

Padding(
            padding: const EdgeInsets.all(3.0),
            child: TextFormField(
              maxLength: 10,
              keyboardType: TextInputType.number,
              validator: (value) {
                if (value.isEmpty) {
                  return 'Enter Number Please';
                }
                
                return null;
              },
              decoration: InputDecoration(
                prefixIcon: Icon(Icons.smartphone),
                prefixText: '+92',
                labelText: 'Enter Phone Number',
                contentPadding: EdgeInsets.zero,
                enabledBorder: OutlineInputBorder(),
                focusedBorder: OutlineInputBorder(
                    borderSide: BorderSide(
                      width: 2, color: Theme
                        .of(context)
                        .primaryColor,
                    )
                ),
                focusColor: Theme
                    .of(context)
                    .primaryColor,
              ),
            ),
          ),

Answer 27

TextField(
  controller: _controller,
  keyboardType: TextInputType.number,
  inputFormatters: <TextInputFormatter>[
  FilteringTextInputFormatter.allow(RegExp(r'[0.0-9.9]')),
 ])

Answer 28

you can use this plugin it's very easy with this plugin

enter code here

link: https://pub.dev/packages/intl_phone_number_input/example