Thank you for contacting us on that matter. Unfortunately our charting components does not support such indication out-of-the-box. However, you can see our RadBusyIndicator which you can use to display loading indication.
I noticed that you have few threads with their Product field set to RadChart but the questions are related to the RadCartesianChart. Please keep in mind that the the RadChart is the old charting component which now is in maintenance mode. Also, we are focused on developing the RadChartView control. On the other hand the RadCartesianChart is part of our new RadChartView suit which have better implementation and performance.
In addition I prepared a sample project that demonstrates RadCartesianChart with a RadBusyIndicator. Please give it a try and let me know if it helps.
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