Hi! I want to be able to generate a data table in code-behind, with the number of columns depending on the number of rows in my data source. I have been able to do this successfully with the xamDataGrid but it seems a similar approach doesn't work for the Multi-Column Combo. The code below generates the error "An item with the same key has already been added" when applied to the multi-column combobox.

Sub Test() 

gridTest.DataSource = CreateTable(10).Rows ' works perfectly
cboMultiColumn.Columns.Clear()
cboMultiColumn .ItemsSource = CreateTable(10).Rows 'does not work :(
End Sub

Private Function CreateTable(cols As Integer) As DataTable
Dim dt As DataTable = New DataTable()
For i = 0 To cols - 1
dt.Columns.Add("Col " & i)
Next
dt.Rows.Add(dt.NewRow)
Return dt 
End Function