The PrintBegin event must fire prior to displaying the dialog. The issue is reproducible in the latest available internal build, thus we logged it for improvement.
Your Telerik points are updated to thank you for pointing the problem to our attention.
Since you are building custom UI to substitute the default Toolbar, you can call the viewer's API
- PrintReport and ExportReport methods, after the rendering of the report in the viewer is done (OnRenderingEnd). If you want to use your own dialogs for both operations, you can use the ReportProcessor
from your custom UI (PrintReport and RenderReport methods).
I hope the provided information is helpful.
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