We have replied to you in the support thread you have opened, please check our response there. For your convenience I'm pasting my response below:
"You can create an external template for the events widget, and subscribe to the Page_PrRender event in the codebehind to check whether the count of the items in your RadListView is 0, if so you can conditionally display/set visibility of the desired text. I'm attaching the template that I've used for your reference."
Big thanks to Steve McNiven-Scott, who brought our attention on the necessity to have such a feature we have logged this as a task for the upcoming releases. You can check the initial discussion on the topic on this forum thread
the Telerik team
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