Simplify International Phone Number Validation in Flutter.

Blog Author: Rajan Metaliya

In today’s globalized digital landscape, mobile applications often require robust phone number validation to accommodate users from diverse geographic locations. Ensuring accurate and seamless validation across multiple countries presents a significant challenge. This article explores ns_intl_phone_input, a Flutter package by Nonstop IO, designed to simplify and enhance international phone number validation.

The Importance of Reliable Phone Number Validation

Effective phone number validation is essential for:

• User Verification: Confirming user identity during registration or authentication.
• Data Integrity: Maintaining accurate and up-to-date contact information.
• Communication: Facilitating SMS or call-based interactions.
• Regional Compliance: Adhering to country-specific formatting rules.

Traditional approaches often rely on complex regular expressions or external APIs, increasing development time and maintenance overhead. ns_intl_phone_input overcomes these challenges by providing a comprehensive, ready-to-use solution.

Key Features and Architectural Overview

ns_intl_phone_input offers a suite of features that streamline the phone number validation process:

Comprehensive Country Selection

• Includes a user-friendly dropdown menu, allowing users to select their country of origin.
• Simplifies associating a phone number with its corresponding country code.

Extensive International Support

• Supports phone number validation for over 200 countries, ensuring global applicability.
• Eliminates the need for developers to maintain country-specific validation logic.

Flexible Number Format Handling

• Intelligently adapts to various phone number formats, accommodating regional differences.
• Removes the need for rigid input formatting, improving the user experience (UX).

Area Code Integration

• Supports area codes, which are essential in many regions.
• Ensures the validation process accurately reflects local phone number structures.

Customization and Extensibility

• Offers a range of customization options, allowing developers to tailor the UI and validation behavior to their specific needs.
• Seamlessly integrates into existing application designs.

IntlTextEditingController

• Provides a custom text editing controller to simplify phone number initialization and clearing.
• Ensures phone numbers are maintained in an international format.

Implementation

Integrating ns_intl_phone_input into a Flutter project is straightforward. The package is available on pub.dev, and installation involves adding the dependency to the pubspec.yaml file and running it. flutter pub get.

dependencies:
  ns_intl_phone_input: ^latest_version        

Usage

Once installed, developers can utilize the NsIntlPhoneInput widget within their UI. The widget provides callbacks for handling country selection and phone number changes, allowing for dynamic updates and validation.

NsIntlPhoneInput(
      textEditingController: _phoneNumberController,
      onPhoneChange: (countrySelection) {
           print(countrySelection);
      },
),        

The package provides methods to initialize the phone number with country codes and clear the number, making it easy to manage the input. The validation can be triggered with the onPhoneChange callback and the results can be used to update the UI or perform other actions.

Customization

ns_intl_phone_input goes beyond basic validation, offering extensive customization to seamlessly integrate into your application’s UI and tailor its functionality.

NsIntlPhoneInput(
      /// Phone number controller
      textEditingController: _phoneNumberController,

      /// Enable or disable validation
      enableValidation: false,
      autovalidateMode: AutovalidateMode.always,

      /// Country selection options for UI experience
      countrySelectOption: const CountrySelectOption(
        countryDialCodeTextStyle: TextStyle(),
        countryIsoCodeTextStyle: TextStyle(),
        defaultText: "000",
        defaultTextStyle: TextStyle(),
        showCode: false,
      ),

      /// Optional to select country selection as dialog or new screen
      countrySelectionType: CountrySelectionTypeEnum.screen,
      focusNode: FocusNode(),
      phoneFieldDecoration: const InputDecoration(),
      phoneInputFontSize: 20,
      validationErrorText: "Validation Message",
      onPhoneChange: (countrySelection) {
        setState(() {
          this.countrySelection = countrySelection;
        });
      },
  ),        

Country Selection Appearance:

• The CountrySelectOption class provides granular control over the country selection dropdown.
• Developers can style country dial codes, ISO codes, and the default text, ensuring visual consistency.

Country Selection Presentation:

• Choose between displaying the country selection as a dialog or a new screen.
• This flexibility allows you to adapt to different UI paradigms and user experience preferences.

Phone Number Input Field Styling:

• The phoneFieldDecoration Property enables comprehensive customization of the phone number input field, allowing you to maintain consistency with your application's design language by adjusting borders, labels, and more.

Additional Customization Options:

• Adjust the font size of the phone input for optimal readability.
• Provide custom validation error messages to enhance user feedback.
• Control the validation behavior using enableValidation and autovalidateMode.

Conclusion

If you’re a Flutter developer tired of wrestling with complex phone number validation logic, ns_intl_phone_input is here to save the day! This powerful package offers a seamless, efficient, and highly customizable solution for handling international phone numbers with ease. With its user-friendly features and global support, you can focus on what truly matters — building awesome apps — without getting bogged down by validation headaches.

As mobile applications continue to connect users worldwide, having a reliable phone number validation tool is a game-changer. So why struggle with tedious regex patterns and API calls? Let ns_intl_phone_input handle the heavy lifting, and watch your app’s user experience and data integrity soar!

#Flutter #MobileDevelopment #AppDevelopment