operator [] method 
    
      
  
dynamic
operator [](
 - ChartDataPointType pointType
)override
     
    
    
  Implementation
  @override
dynamic operator [](ChartDataPointType pointType) {
  switch (pointType) {
    case ChartDataPointType.y:
      return y!;
    case ChartDataPointType.high:
      return high!;
    case ChartDataPointType.low:
      return low!;
    case ChartDataPointType.open:
      return open!;
    case ChartDataPointType.close:
      return close!;
    case ChartDataPointType.volume:
      return volume!;
    case ChartDataPointType.median:
      return median!;
    case ChartDataPointType.mean:
      return mean!;
    case ChartDataPointType.outliers:
      return outliers!;
    case ChartDataPointType.bubbleSize:
      return bubbleSize!;
    case ChartDataPointType.cumulative:
      return cumulative!;
  }
}