flutter_address_form/example/lib/main.dart

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

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

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

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: AddressFormExample(),
    );
  }
}

class AddressFormExample extends StatelessWidget {
  AddressFormExample({super.key});

  // final RegExp zipcodeRegExp = RegExp(r'^[1-9][0-9]{3}\s?[a-zA-Z]{2}$');

  final _addressController = AddressController(
    zipCodeValidator: (text) {
      if (text != null) {
        if (text.isEmpty) {
          return 'Can\'t be empty';
        }
        if (!RegExp(r'^[1-9][0-9]{3}\s?[a-zA-Z]{2}$').hasMatch(text)) {
          return 'Invalid zipcode';
        }
      }
      return null;
    },
    housenumberValidator: (text) {
      if (text != null) {
        if (text.isEmpty) {
          return 'Can\'t be empty';
        }
        if (text.length >= 3 || int.tryParse(text) == null) {
          return 'Invalid number';
        }
      }
      return null;
    },
    suffixValidator: (text) {
      if (text != null) {
        if (text.isNotEmpty && RegExp(r'/^[a-z]*$/').hasMatch(text)) {
          return 'Invalid prefix';
        }
      }
      return null;
    },
    streetValidator: (text) {
      if (text != null) {
        if (text.isEmpty) {
          return 'Can\'t be empty';
        }
      }
      return null;
    },
    cityValidator: (text) {
      if (text != null) {
        if (text.isEmpty) {
          return 'Can\'t be empty';
        }
      }
      return null;
    },
    onAutoComplete: (address) {
      return address;
    },
  );

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Address Form'),
      ),
      body: Column(
        children: [
          AddressForm(
            onSubmit: (value) => value,
            controller: _addressController,
          ),
          ElevatedButton(
            onPressed: () {
              _addressController.validate();
            },
            child: const Text('Validate'),
          )
        ],
      ),
    );
  }
}