CODE EXAMPLE FOR DART

dart flutter countdown timer

TweenAnimationBuilder<Duration>(
  duration: Duration(minutes: 3),
  tween: Tween(begin: Duration(minutes: 3), end: Duration.zero),
  onEnd: () {
    print('Timer ended');
  },
  builder: (BuildContext context, Duration value, Widget? child) {
    final minutes = value.inMinutes;
    final seconds = value.inSeconds % 60;
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 5),
      child: Text('$minutes:$seconds',
               textAlign: TextAlign.center,
               style: TextStyle(
               color: Colors.black,
               fontWeight: FontWeight.bold,
               fontSize: 30)));
    }),