car_customer_app/lib/widgets/count_down_timer.dart

import 'package:flutter/material.dart';

class CountDownTimer extends StatefulWidget {
  const CountDownTimer({
    Key? key,
    int? secondsRemaining,
    this.countDownTimerStyle,
    this.whenTimeExpires,
    this.countDownFormatter,
  })
      : secondsRemaining = secondsRemaining,
        super(key: key);

  final int? secondsRemaining;
  final Function? whenTimeExpires;
  final Function? countDownFormatter;
  final TextStyle ?countDownTimerStyle;

  State createState() => new _CountDownTimerState();
}

class _CountDownTimerState extends State<CountDownTimer>
    with TickerProviderStateMixin {
  late AnimationController _controller;
  late Duration duration;

  String get timerDisplayString {
    Duration duration = _controller.duration! * _controller.value;
    return widget.countDownFormatter != null
        ? widget.countDownFormatter!(duration.inSeconds)
        : formatHHMMSS(duration.inSeconds);
    // In case user doesn't provide formatter use the default one
    // for that create a method which will be called formatHHMMSS or whatever you like
  }

  @override
  void initState() {
    super.initState();
    duration = new Duration(seconds: widget.secondsRemaining ?? 0);
    _controller = new AnimationController(
      vsync: this,
      duration: duration,
    );
    _controller.reverse(from: widget.secondsRemaining!.toDouble());
    _controller.addStatusListener((status) {
      if (status == AnimationStatus.completed || status == AnimationStatus.dismissed) {
        widget.whenTimeExpires!();
      }
    });
  }

  @override
  void didUpdateWidget(CountDownTimer oldWidget) {
    if (widget.secondsRemaining != oldWidget.secondsRemaining) {
      setState(() {
        duration = new Duration(seconds: widget.secondsRemaining ?? 0);
        _controller.dispose();
        _controller = new AnimationController(
          vsync: this,
          duration: duration,
        );
        _controller.reverse(from: widget.secondsRemaining?.toDouble());
        _controller.addStatusListener((status) {
          if (status == AnimationStatus.completed) {
            widget.whenTimeExpires!();
          } else if (status == AnimationStatus.dismissed) {
            print("Animation Complete");
          }
        });
      });
    }
  }

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

  @override
  Widget build(BuildContext context) {
    return new Center(
      child: AnimatedBuilder(
          animation: _controller,
          builder: (_, Widget? child) {
            return Text(
              timerDisplayString ??"",
              style: widget.countDownTimerStyle,
            );
          }),);
  }
}

String formatHHMMSS(int seconds) {
  int hours = (seconds / 3600).truncate();
  seconds = (seconds % 3600).truncate();
  int minutes = (seconds / 60).truncate();

  String hoursStr = (hours).toString().padLeft(2, '0');
  String minutesStr = (minutes).toString().padLeft(2, '0');
  String secondsStr = (seconds % 60).toString().padLeft(2, '0');

  if (hours == 0) {
    return "$minutesStr:$secondsStr";
  }

  return "$hoursStr:$minutesStr:$secondsStr";
}