ArcPainter constructor
      
      ArcPainter()
     
    
    
Implementation
ArcPainter(this.radius, this.strokeWidth, this.arcStart, this.arcEnd,
    this.color, this.notifier)
    : super(repaint: notifier) {
  circlePaint
    ..color = color
    ..strokeWidth = strokeWidth
    ..style = PaintingStyle.stroke
    ..strokeCap = StrokeCap.round;
}