datetime_loop 1.3.1

A Flutter package that provides a widget to listen to the system's datetime and trigger a rebuild based on the specified time unit.

example/lib/main.dart

import 'dart:math' as math;
import 'package:datetime_loop/datetime_loop.dart';
import 'package:flutter/material.dart';
import 'package:group_button/group_button.dart';

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

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

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final GroupButtonController _controller =
      GroupButtonController(selectedIndex: 1);

  final ValueNotifier<TimeUnit> _timeUnitNotifier =
      ValueNotifier(TimeUnit.seconds);

  late DateTimeLoopController _dateTimeController;

  @override
  void initState() {
    super.initState();
    _dateTimeController = DateTimeLoopController(
      timeUnit: TimeUnit.seconds,
      triggerOnStart: true,
    );
  }

  @override
  void dispose() {
    _dateTimeController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: SafeArea(
        child: Scaffold(
          appBar: AppBar(
            title: const Text("Example"),
          ),
          body: ListView(
            shrinkWrap: true,
            children: [
              GroupButton<TimeUnit>(
                controller: _controller,
                buttons: TimeUnit.values,
                onSelected: (timeUnit, index, isSelected) async {
                  _timeUnitNotifier.value = timeUnit;
                  _dateTimeController.dispose();
                  _dateTimeController = DateTimeLoopController(
                    timeUnit: timeUnit,
                    triggerOnStart: true,
                  );
                  setState(() {});
                },
                buttonTextBuilder: (__, timeUnit, context) {
                  return timeUnit.name;
                },
              ),
              const SizedBox(
                height: 12,
              ),
              ValueListenableBuilder<TimeUnit>(
                  valueListenable: _timeUnitNotifier,
                  builder: (context, timeUnit, __) {
                    return ExampleComponent(timeUnit: timeUnit);
                  }),
              const SizedBox(
                height: 12,
              ),
              StreamBuilder(
                  stream: _dateTimeController.dateTimeStream,
                  initialData: DateTime.now(),
                  builder: (context, snapshot) {
                    final DateTime dateTime = snapshot.data!;
                    return Column(
                      children: [
                        Container(
                          width: 200,
                          height: 200,
                          color: Color((math.Random().nextDouble() * 0xFFFFFF)
                                  .toInt())
                              .withOpacity(1.0),
                          child: const Center(
                            child: Text(
                                'Widget restate based on DateTimeLoopController'),
                          ),
                        ),
                        Text(
                            '${dateTime.hour}:${dateTime.minute}:${dateTime.second}'),
                      ],
                    );
                  })
            ],
          ),
        ),
      ),
    );
  }
}

class ExampleComponent extends StatelessWidget {
  final TimeUnit timeUnit;

  const ExampleComponent({super.key, required this.timeUnit});

  @override
  Widget build(BuildContext context) {
    return DateTimeLoopBuilder(
      timeUnit: timeUnit,
      triggerOnStateChange: true,
      builder: (context, dateTime, child) {
        return Column(
          children: [
            Container(
              width: 200,
              height: 200,
              color: Color((math.Random().nextDouble() * 0xFFFFFF).toInt())
                  .withOpacity(1.0),
            ),
            Text('${dateTime.hour}:${dateTime.minute}:${dateTime.second}'),
            child!
          ],
        );
      },
      child: Container(
        width: 200,
        height: 200,
        color: Color((math.Random().nextDouble() * 0xFFFFFF).toInt())
            .withOpacity(1.0),
        child: const Center(
          child: Text(
              'Widget will not be affected by the change of the DateTimeLoopBuilder state. (Color will changed only if the state of ExampleComponent is changed)'),
        ),
      ),
    );
  }
}