The Q3 release is coming in about a week and it will provide a lot of improvements in the control - full databinding for pie charts so you do not have to create items programmatically and a ClientTemplate for the labels and tooltips in the items so you can add more columns from your datasource there. More information about the improvements we have made on the control is available in this blog post
. I am sorry to say that for the time being all the desired functionality is not available. You can set the DataFormatString with data you have in the code-behind, but it will still be static and not per row.
the Telerik team
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