I am not sure I understand you fully. You mentioned that showing all labels does not look very nice. Are you showing the value in the labels? Or are you showing some text (like a category name).
If you are showing category name - I would suggest not to show this category name in the item label, but show it in the legend and in the item label show the value.
If you are showing values in the item labels - I do not see an obvious reason not to like the results. If you can clear that, than we might be able to help. You can send us a screenshot of the output and a drawing of the desired results.
Now, for the second part of your question - yes there is way to show the label of a particular slice. It can not be achieved with out-of-the-box means but you can implement it manually. You just need to find the hovered item in code behind and set its labels visibility to Visible (and collapse all others).
The code below should help you understand what I have in mind.
.radChart.SeriesMappings.SeriesDefinition.InteractivitySettings.HoverScope = Telerik.Windows.Controls.Charting.InteractivityScope.Item;
sender, Telerik.Windows.Controls.Charting.ChartHoverChangedEventArgs e)
ChartArea chartArea = sender
var hoveredDataItems = e.HoveredItems.Select(dp => dp.DataItem);
item.Visibility = System.Windows.Visibility.Visible;
item.Visibility = System.Windows.Visibility.Collapsed;
You can examine our demos here
where you can also get some new ideas.
All the best,
the Telerik team
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