Sorting a list of items based on their date property

readme.md

Sorting a list of transactions based on their date property

Created with <3 with dartpad.dev.

main.dart

// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  final String title;

  const MyHomePage({
    Key? key,
    required this.title,
  }) : super(key: key);

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: Column(
        // TODO: you can feed your list view builder with dates from today, yesterday and beyond that will 
        // be loaded dynamically (not all at once but using infinite scrolling / pagination)
        children: List.generate(5, (index) {
          /// You feed your transactions to this function and it maps it to an object
          /// that sections the transactions based on their date
          final dateSection = mapTransactionsToDateWidget(DateTime.now(), listOfTransactions());
          
          return Column(
            children: [
              Text(dateSection.date.toString()),
              Column(
                children: List.generate(dateSection.transactions.length, (index) => Text(dateSection.transactions[index].name),),
              ),
            ],
          );
        }),
      ),
    );
  }
  
  SortedTransactions mapTransactionsToDateWidget(DateTime date, List<Transaction> transactions) {
    // TODO: change isAtSameMomentAs to isSameDayAs not sure the exact method name this is just an example (you can use moment package) 
    return SortedTransactions(date: date, transactions: transactions.where((transaction) => transaction.date.isAtSameMomentAs(date)).toList(),);
  }
  
  
  /// This is your list of transactions
  List<Transaction> listOfTransactions() {
    return [
      Transaction(name: 'Test 1', date: DateTime.now()),
      Transaction(name: 'Test 2', date: DateTime.now()),
      Transaction(name: 'Test 3', date: DateTime.now()),
    ];
  }
}

class SortedTransactions {
  final DateTime date;
  final List<Transaction> transactions;
  
  SortedTransactions({required this.date, required this.transactions});
}

class Transaction {
  final String name;
  final DateTime date;
  
  Transaction({required this.name, required this.date});
}