smart_phone_numb 0.3.0

A Flutter phone number field that detects the user's country from the device timezone and validates the number length for the selected country.

Smart Phone Number Field

A Flutter package that provides a smart phone number input field with automatic country code and number field length detection based on the user's timezone.

Features

• Smart Country Detection: Automatically suggests the correct country code based on user's timezone
• Dynamic Phone Number Validation: Sets minimum and maximum phone number length limits based on the selected country
• Country Code Picker Integration: Easy-to-use country selector with flag display
• Real-time Validation: Validates phone numbers according to country-specific rules
• Support for 221+ Countries: Comprehensive database of phone number formats worldwide

Getting Started

Add this package to your pubspec.yaml:

dependencies:
  smart_phone_numb: ^0.3.0

Then run:

flutter pub get

Usage

Import the package and use the SmartPhoneNumberField widget:

import 'package:smart_phone_numb/smart_phone_numb.dart';

SmartPhoneNumberField(
  defaultCountryCode: 'US',
  onChanged: (PhoneNumberData data) {
    print('Full number: ${data.fullPhoneNumber}');
    print('Country: ${data.countryCode}');
    print('Dial code: ${data.dialCode}');
    print('Number: ${data.phoneNumber}');
  },
)

Parameters

Parameter	Type	Default	Description
defaultCountryCode	String	'US'	Fallback country code when timezone detection fails
initialCountryCode	String?	null	Country to start with; skips timezone detection when set
favoriteCountries	List<String>	[]	Country codes shown at top of the picker
onChanged	void Function(PhoneNumberData)?	null	Called when the phone number or country changes
controller	TextEditingController?	null	Controls the phone number text (without dial code)
decoration	InputDecoration?	null	Custom input decoration for the text field
style	TextStyle?	null	Text style for the phone number input
enabled	bool	true	Whether the field accepts input
showCounterText	bool	false	Whether to show the character counter
autovalidateMode	AutovalidateMode?	null	When the field validates itself; defaults to the enclosing Form's mode

PhoneNumberData

The onChanged callback provides a PhoneNumberData object with:

Property	Type	Description
dialCode	String	The dial code (e.g., '+1')
countryCode	String	Two-letter ISO code (e.g., 'US')
phoneNumber	String	The entered number without country code
fullPhoneNumber	String	Complete number with dial code

How It Works

1. Automatic Detection: When the widget loads, it detects the user's timezone (skipped if initialCountryCode is set)
2. Country Mapping: Maps the timezone to the most likely country code using a built-in table of 500+ IANA timezones and legacy aliases
3. Smart Validation: Automatically sets the correct phone number length limits
4. User Override: Users can manually select a different country if needed

If detection fails or the timezone is unknown, the field uses defaultCountryCode and shows a small warning icon.

Utilities

The lookup tables are exported too, if you need them outside the widget:

countryCodeForTimezone('Asia/Kolkata'); // 'IN'
phoneNumberLengths['GB'];               // {'min': 7, 'max': 10}

Example

class MyForm extends StatelessWidget {
  const MyForm({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Form(
          child: SmartPhoneNumberField(
            defaultCountryCode: 'DE',
            favoriteCountries: const ['+49', 'DE', '+44', 'GB'],
            decoration: const InputDecoration(
              labelText: 'Mobile Number',
              border: OutlineInputBorder(),
            ),
            onChanged: (data) {
              debugPrint('Number: ${data.fullPhoneNumber}');
            },
          ),
        ),
      ),
    );
  }
}

Dependencies

This package uses:

• country_code_picker for the country selection UI
• flutter_timezone for automatic timezone detection

Additional Information

• Issues & Contributions: GitHub Repository
• Releasing: See PUBLISHING.md
• License: See LICENSE file