An animated clock toggle widget for setting alarms in lists or similliar.

animated_clock_toggle.dart

class AnimatedClock extends StatefulWidget {
  final bool isToggled;
  const AnimatedClock({
    Key key,
    this.isToggled,
  }) : super(key: key);

  @override
  _AnimatedClockState createState() => _AnimatedClockState();
}

class _AnimatedClockState extends State<AnimatedClock> with SingleTickerProviderStateMixin {
  AnimationController _animationController;
  Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _animationController = AnimationController(vsync: this, duration: Duration(milliseconds: 300));
    _animation = Tween(begin: 0.0, end: 10.0).chain(CurveTween(curve: Curves.elasticIn)).animate(_animationController)
      ..addStatusListener((status) {
        if (status == AnimationStatus.completed) {
          _animationController.reverse();
        }
      });
  }

  @override
  void didUpdateWidget(AnimatedClock oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (!oldWidget.isToggled && widget.isToggled) {
      _animationController.forward();
    }
  }

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

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
        animation: _animation,
        builder: (BuildContext context, child) {
          return Padding(
            padding: EdgeInsets.only(left: _animation.value + 10.0, right: 10.0 - _animation.value),
            child: Icon(
              widget.isToggled ? Icon.alarm_on : Icon.alarm_off,
              size: 20.0,
            ),
          );
        });
  }
}