time_remaining 2.0.0+1

time_remaining tells you in the form of a countdown the exact time remaining until the time you want is fulfilled.

example/lib/main.dart

// ignore_for_file: avoid_print

import 'package:flutter/material.dart';
import 'package:time_remaining/time_remaining.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: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Padding(
        padding: const EdgeInsets.all(16),
        child: Wrap(
          runSpacing: 8,
          spacing: 8,
          children: [
            TimeRemaining(
              duration: const Duration(
                days: 1,
                hours: 12,
              ),
              onTimeOver: () {
                print("TIME OVER");
              },
            ),
            const TimeRemaining(
              duration: Duration(
                days: 1,
              ),
              style: TextStyle(
                color: Colors.green,
              ),
            ),
            const TimeRemaining(
              duration: Duration(
                hours: 1,
              ),
              style: TextStyle(
                fontWeight: FontWeight.bold,
                color: Colors.green,
              ),
              warningDuration: Duration(
                hours: 1,
              ),
              warningsStyle: TextStyle(
                color: Colors.yellow,
              ),
            ),
            const TimeRemaining(
              duration: Duration(
                minutes: 30,
              ),
              warningDuration: Duration(
                hours: 1,
              ),
              warningsStyle: TextStyle(
                color: Colors.yellow,
              ),
              dangerDuration: Duration(
                minutes: 30,
              ),
              dangerStyle: TextStyle(
                color: Colors.red,
                fontWeight: FontWeight.bold,
              ),
            ),
          ],
        ),
      ),
    );
  }
}