Thank you so much for the provided details. I am afraid this is also not supported out-of-the-box in Kendo UI Chart, however I can suggest you the following workaround:
- Create a custom <div> element with Loading message and position it over the Chart;
- Once the data is loaded (i.e. in the DataBound event) hide the aforementioned <div>.
For your convenience here is a simple jsFiddle example.
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