Managing Chart Items

[Chris Thierry]

Hi,

    Is there any way of managing items in a PieChart? for example I want to show in my chart products and percentages. Is the percentage is less than 10%, I will create an item "Other". Every product under 10% it will be in this item "Other". I can say 20 or 30 percent...I want also to define this value. In this way I can show always the same qty of items and add the "Other" item according to this logic.

Can I do this using Chart Telerik RadControl?
Thank you.

    

[Tsvetie]

Hello Chris Thierry,
RadChart for Silverlight does not support this feature out of the box. You can, however, achieve the described result using one the the following approaches:

• Construct your data source in such a way, so that all items with value less than 10% are added to an "Other" item.
• Use the DataBound event of the chart to remove all items with YValue less than 10% and add them to a new "Other" item. For example:

  void RadChart1_DataBound(object sender, ChartDataBoundEventArgs e)
  {
      DataSeries series = RadChart1.DefaultView.ChartArea.DataSeries[0];
  
      double sum = 0d;
      foreach (DataPoint point in series)
      {
          sum += point.YValue;
      }
  
      DataPoint[] seriesItems = new DataPoint[series.Count];
      ((Collection<DataPoint>)series).CopyTo(seriesItems, 0);
  
      double otherDataPointValue = 0d;
      for (var i = 0; i < seriesItems.Length; i++)
      {
          DataPoint dataPoint = seriesItems[i];
          if (dataPoint.YValue / sum < 0.1d)
          {
              otherDataPointValue += dataPoint.YValue;
              series.Remove(dataPoint);
          }
      }
  
      DataPoint otherDataPoint = new DataPoint();
      otherDataPoint.YValue = otherDataPointValue;
      otherDataPoint.LegendLabel = "Other";
  
      series.Add(otherDataPoint);
  }

Regards,
Tsvetie
the Telerik team