Unfortunately, displaying the week numbers in the TimeRuler is not possible, since they won't get update when the date range is changed. However, you can display them in the group headers of each view. Please find attache a sample project which illustrates this. The project is for Silverlight, however, the logic is the same. It contains also the full xaml of the ScheduleView, which will be of no use to you. Please verify that the templates used in MainPage.xaml are correct for WPF. For more information about customizing the Group Headers you can refer to this online demo.
Hope this helps. Please let us know if you have further questions.
All the best,
the Telerik team
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