Hi Jayson,

I ran your sample and I reproduced the error. The problem is caused by the fact that you are setting the Style of the column to DropDownList. So you can simply remove that line of code and it works fine.

Why that line of code causes a problem is puzzling, though. I can't see any reason why that should not be a valid thing to do. It might be a bug, so I'm going to ask Infragistics Developer Support to create a case for you and write this up for developer review.

Hi Mike,

Enclosed please find a sample that recreates the issue.

Thanks for the follow up and please send me regarding any questions.

Jayson.

Hi Magued, 

I can't get your code to compile. Can you put together a small sample project and attach it to your post?

Hi Boris,

I left this issue a while ago and now it is coming back to be one of the requirements. I have looked at the forms and I can't find an exact answer. I have also updated to the latest version 11.2.20112.2135 and I am getting the same issue.

You can build a sample so easy by adding a grid and an ultracomboeditor:

Enclosed please find the code, you can copy it and paste it:

Public Class Form1

Private MakeOrdersDataTable As DataTable

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'TODO: This line of code loads data into the 'TEST_DBDataSet.Book1' table. You can move, or remove it, as needed.
UltraComboEditor1.DataSource = MakeCustomerDataTable()
UltraComboEditor1.CheckedListSettings.CheckBoxStyle = Infragistics.Win.CheckStyle.CheckBox
UltraComboEditor1.CheckedListSettings.CheckBoxAlignment = ContentAlignment.MiddleRight
UltraComboEditor1.CheckedListSettings.EditorValueSource = Infragistics.Win.EditorWithComboValueSource.CheckedItems
UltraComboEditor1.CheckedListSettings.ListSeparator = ", "
UltraComboEditor1.CheckedListSettings.ItemCheckArea = Infragistics.Win.ItemCheckArea.CheckBox

End Sub

Private Sub UltraButton2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles UltraButton2.Click
Dim dataSet As New DataSet()
dataSet.Tables.Add(MakeCustomersDataTable)
Me.UltraGrid1.DataSource = dataSet

End Sub

Private Function MakeCustomersDataTable() As DataTable
' Declare a DataTable to contain the program generated data
Dim dataTable As New DataTable("Customers")

Dim colWork As New DataColumn("CustomerID", GetType(Int32))
dataTable.Columns.Add(colWork)

' Add CustomerID column to key array and bind to DataTable
Dim Keys(0) As DataColumn
Keys(0) = colWork
dataTable.PrimaryKey = Keys

' Create and add a CustomerName column
colWork = New DataColumn("CustomerName", GetType(Object))
' colWork.MaxLength = 50
dataTable.Columns.Add(colWork)

' Create and add a LastOrderDate column
colWork = New DataColumn("LastOrderDate", GetType(Date))
dataTable.Columns.Add(colWork)

' Add a row
Dim row As DataRow = dataTable.NewRow()
row("CustomerID") = 1
row("CustomerName") = "John"
row("LastOrderDate") = Now
dataTable.Rows.Add(row)

' Add another row
row = dataTable.NewRow()
row("CustomerID") = 2
row("CustomerName") = "Fred"
row("LastOrderDate") = Now.AddDays(-101)
dataTable.Rows.Add(row)

Return dataTable
End Function

Private Function MakeCustomerDataTable() As DataTable
' Declare a DataTable to contain the program generated data
Dim dataTable As New DataTable("Customer")

Dim colWork As New DataColumn("CustomerName", GetType(String))
colWork.MaxLength = 50
dataTable.Columns.Add(colWork)
Dim row As DataRow = dataTable.NewRow()

row("CustomerName") = "John"

dataTable.Rows.Add(row)

row = dataTable.NewRow()

row("CustomerName") = "Fred"

dataTable.Rows.Add(row)

Return dataTable
End Function

Private Sub UltraGrid1_InitializeLayout(ByVal sender As System.Object, ByVal e As Infragistics.Win.UltraWinGrid.InitializeLayoutEventArgs) Handles UltraGrid1.InitializeLayout

e.Layout.Bands(0).Columns("CustomerName").EditorComponent = UltraComboEditor1
e.Layout.Bands(0).Columns("CustomerName").Style = UltraWinGrid.ColumnStyle.DropDownList
e.Layout.Bands(0).Columns("CustomerName").CellActivation = Activation.AllowEdit

End Sub
End Class

When you run the sample:

1) Click on Ultrabutton1 the grid will be poulated.

2) In the Grid CustomerName cfiled lick on the dropdown  and choose 2 values John and Fred.

3) Click on the Ultrabutton again and you will get the error message.

If you want I can attach the sample.

Thanks, Magued