Small Flutter Example

main.dart

import 'package:flutter/material.dart';

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

final invoices = [
  Invoice(
    invoiceId: 'INV-001',
    invoiceDate: '2021-10-01',
    invoiceAmount: 100.00,
    invoiceStatus: 'paid',
  ),
  Invoice(
    invoiceId: 'INV-002',
    invoiceDate: '2021-10-02',
    invoiceAmount: 200.00,
    invoiceStatus: 'unpaid',
  ),
  Invoice(
    invoiceId: 'INV-003',
    invoiceDate: '2021-10-03',
    invoiceAmount: 300.00,
    invoiceStatus: 'unknown',
  ),
];

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
      body: Center(
        child: Column(
          children: [
            /// ... -> Spread operator
            ...invoices.map(
              (invoice) => InvoiceDefinition(invoice: invoice),
            )
          ],
        ),
      ),
    ));
  }
}

class InvoiceDefinition extends StatelessWidget {
  final Invoice invoice;

  const InvoiceDefinition({
    super.key,
    required this.invoice,
  });

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        Row(
          children: [
            Text('Invoice ID: ${invoice.invoiceId}'),
            Text('Invoice Date: ${invoice.invoiceDate}'),
            Text('Invoice Amount: ${invoice.invoiceAmount}'),
          ],
        ),

        /// Switch expression
        switch (invoice.invoiceStatus) {
          // or Text(context.mt.paid)
          'paid' => const Text('Invoice Status: Paid'),
          // or Text(context.mt.unpaid)
          'unpaid' => const Text('Invoice Status: Unpaid'),
          // or Text(context.mt.unknown)
          _ => const Text('Invoice Status: Unknown'),
        }
      ],
    );
  }
}

class Invoice {
  String invoiceId;
  String invoiceDate;
  double invoiceAmount;
  String invoiceStatus;

  Invoice({
    required this.invoiceId,
    required this.invoiceDate,
    required this.invoiceAmount,
    required this.invoiceStatus,
  });

  factory Invoice.fromJson(Map<String, dynamic> json) {
    return Invoice(
      invoiceId: json['invoiceId'],
      invoiceDate: json['invoiceDate'],
      invoiceAmount: json['invoiceAmount'],
      invoiceStatus: json['invoiceStatus'],
    );
  }

  Map<String, dynamic> toJson() => {
        'invoiceId': invoiceId,
        'invoiceDate': invoiceDate,
        'invoiceAmount': invoiceAmount,
        'invoiceStatus': invoiceStatus,
      };

  @override
  String toString() {
    return 'Invoice{invoiceId: $invoiceId, invoiceDate: $invoiceDate, invoiceAmount: $invoiceAmount, invoiceStatus: $invoiceStatus}';
  }
}