These columns don't currently have unique values

[Itzy]

I get the error "These columns don't currently have unique values" when I have more than one NULL parent value in my list. The element Ids are all unique but I always get the error. Please help.

Sample data
parentId elementId  elementText
NULL     116            ​Text1
116         2108 ​         Text2
2108       2109          Text3
2108       2110           Text4
NULL      72              Text5
72           655             Text6
72           660              Text7
72 672

 

[Ivan Danchev]

Hello,

I am afraid I was not able to reproduce the issue.

Please find attached a sample project that demonstrates RadTreeView binding to a custom class and to hierarchical data that we get from the Northwind sample data base. Multiple root nodes have null ParentID values and this does not cause any error to be returned.
 
Regards,
Ivan Danchev
Telerik