Sorting items in a list based on their dates

readme.md

Sorting items in a list based on their dates

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> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: Column(
        children: List.generate(dateTimes().length, (index) {
          final dateSection = mapTransactionsToDateSection(dateTimes()[index], listOfTransactions());
          return Column(children: [
            Text(dateSection.date.toString()),
            Column(
            children: List.generate(dateSection.transactions.length, (index) => Column(
            children: [
              Text(dateSection.transactions[index].name),
            ],))
          ),
        ]);
        })
      )
    );
  }
  
  List<DateTime> dateTimes() {
    return [
      DateTime.now(),
      DateTime.now().add(const Duration(seconds: 30)),
      DateTime.now().add(const Duration(seconds: 100)),
    ];
  }
  
  /// map today, yesterday and previous days to DateSection
  DateSection mapTransactionsToDateSection(DateTime date, List<Transaction> transactions) {
    return DateSection(date: date, transactions: transactions.where((transaction) => transaction.date.isAtSameMomentAs(date)).toList());
  }
  
  /// Your list of transactions
  List<Transaction> listOfTransactions() {
    return [
      Transaction(name: "Test 1", date: DateTime.now()),
      Transaction(name: "Test 2", date: DateTime.now().add(const Duration(seconds: 30))),
      Transaction(name: "Test 3", date: DateTime.now()),
      Transaction(name: "Test 4", date: DateTime.now().add(const Duration(seconds: 30))),
      Transaction(name: "Test 5", date: DateTime.now().add(const Duration(seconds: 100))),
    ];
  }
}

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

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