There is no client-side binding, the report must be processed and rendered on the server. Thus to display a report in the Silverlight viewer you need to have a running Reporting WCF service.
To display a report from TRDX file you can use the default service implementation and set the viewer's Report property to the path to the TRDX file on the server. If you need to customize the report, you can use a custom report resolver per my colleague's post here.
I hope the above information helps you.
Regards,
Stef
Telerik
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