I tried to reproduce the problem you described, but without success. Please take a look at my test page, compare it with your setup and let me know if there are differences. Basically I have used the implementation from the online demo HtmlChart / Programmatic Creation
and I have replaced the UpdatePanel with a RadAjaxManager. The effect appears to be the same as shown in this
As explained in the Client-side API
help article, the method loadData
invokes a light callback to the server in order to send the chart data to the client, which allows you to populate RadHtmlChart after the page is loaded. If you want to change the data that is loaded in the RadHtmlChart control, you will have to initiate an AJAX request to the server in order to specify the new datasource.
Please check the attached sample and describe the changes that should be made in order to recreate your scenario. If this is not possible, you can also prepare and send a simple, runnable page
that isolates the problem so that I can examine it locally and provide a concrete solution.
the Telerik team
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