How do i add label to the pie chart slice when a particular slice is touched using coreplot?

I had drawn a pie chart using core-plot. I need to display the 开发者_运维技巧item name when a particular slice is touched. can anyone suggest me a solution to achieve this?

You can handle individual slice events by implementing CPPieChartDelegate methods. Declare CPPieChartDelegate protocol and implement the method (void)pieChart:sliceWasSelectedAtRecordIndex: . Set the delegate of piechart to self(controller). This method gives you which slice(index) is selected. And now for drawing the label, you have to re-draw the pie chart, specifying which slice to be labeled. You can set empty string to labels for other slices.

The iPhone version of CPTTestApp (in the Core Plot examples folder) shows how to display the selected slice index. It displays the index in the graph title, but you just as easily display it in a Core Plot annotation or in a separate UI control.