The column editors are predefined depending on the type of column that you use. If you need to have custom controls in the column editor then it is recommended to use the TreeListTemplateColumn and define the control in its EditItemTemplate.
Also have in mind that the columns in the treelist support only one column editor and cannot render different controls for each row unless you manually hide or show specific controls in the template.
All the best,
the Telerik team
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