There are no restrictions on the number of the rows and columns shown by RadTreeListView.
Also, you do not have to create the columns dynamically as you scroll horizontally, because the control uses column (and row) virtualization and only the visible ones are realized.
Still, if you want to know how to create columns dynamically, please check this topic
(it is for RadGridView, but RadTreeListView inherits the GridViewDataControl, so the article is applicable).
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