You can get the selected item of a RadTreeView with its SelectedItem property.
However, you can keep in mind that the containers of the children of a RadTreeView are generated when they are expanded for the first time. If the selected item is in lower level in the tree hierarchy and has not been expanded yet, the SelectedItem property will return Null. This is caused by the fact that the selected RadTreeViewItem is not generated.
In order to get a selected item which has not been expanded yet (therefore is not generated) you can use the GetItemByPath() method. For your convenience I attached a sample project which demonstrates the use of this method.
Please let me know if you need any further assistance.
Regards,
Martin
Telerik
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