I've found what seems to be a strange bug on the pie chart in the XamChart control. I have a report that returns data for a given time period, grouped into days. The application is set up to ensure that there is a datapoint for each day of the date range, so if there is not actual data returned by the database query for one of the days in the range, a datapoint is created with a value of 0.
When I run this report for the month of August for example, the database returns data for only the 28th, 29th and 30th. The other days are all inserted into the single chart series as 0. When the chart type is set to cylinder, this displays accurately, with only data showing for those 3 days. When I switch it to a pie chart, and switch to an exploded view, it displays what seems to be a 4th datapoint that is as thin as can be, and when I hover over this extra slice, the tooltip (that is set to be the date that the datapoint represents) flickers between the 10th and 11th of the month.
Is this something that anyone else has come across?
This is because even it is 0, there is a slice. If you want to hide them you can set StrokeThickness to 0, on these data points.
<igChart:Series.DataPoints>
<igChart:DataPoint Value="30" />
<igChart:DataPoint Value="20" />
<igChart:DataPoint Value="0" StrokeThickness="0" />
…
Unfortunately, setting the stroke thickness to 0 doesn't seem to make any difference. Is it because each data point has a label, even if it's value is 0? This is the only other property on the data point that I can see that I can imagine might cause this problem.