circle_path_metric.dart

  @override
  void paint(Canvas canvas, Size size) {
    var path = createPath();
    PathMetrics pathMetrics = path.computeMetrics();
    for (PathMetric pathMetric in pathMetrics) {
      Path extractPath = pathMetric.extractPath(
        0.0,
        pathMetric.length * progress,
      );
      canvas.drawPath(extractPath, myPaint);
    }
  }