LookupControl: fix values disappearing from popup on second open

Controls.LookupGrid/LookupControl3.vb

@@ -49,6 +49,7 @@ Public Class RepositoryItemLookupControl3
         SetDropdownButtonEnabled(_MultiSelect)
     End Sub
 
+    Private Const NAME_DATATABLE_INTERNAL = "__INTERNAL_DATATABLE__"
     Private Const TAG_DROPDOWN = "openDropdown"
     Private Const TAG_BUTTON_LOOKUP_FORM = "openLookupForm"
 
@@ -165,8 +166,12 @@ Public Class RepositoryItemLookupControl3
             NullText = Values.FirstOrDefault()
         End If
 
-        If DataSource Is Nothing Then
-            Dim oDataTable As New DataTable()
+        ' If No external Datasource is supplied, create one containing the currently selected values
+        ' If the current datasource is the internal one, update it
+        If DataSource Is Nothing OrElse (TypeOf DataSource Is DataTable AndAlso DirectCast(DataSource, DataTable).TableName = NAME_DATATABLE_INTERNAL) Then
+            Dim oDataTable As New DataTable() With {
+                .TableName = NAME_DATATABLE_INTERNAL
+            }
             oDataTable.Columns.Add(New DataColumn("Data", GetType(String)))
 
             For Each oValue In Values
@@ -248,9 +253,9 @@ Public Class RepositoryItemLookupControl3
         If DataSource IsNot Nothing AndAlso DataSource.Columns.Count > 0 Then
             Dim oFirstColumn As String = DataSource.Columns.Item(0).ColumnName
 
-            Dim oWrapped = SelectedValues.Select(Function(v As String)
-                                                     Return $"'{v}'"
-                                                 End Function).ToArray()
+            Dim oWrapped = SelectedValues.
+                Select(Function(v As String) $"'{v}'").
+                ToArray()
             Dim oValueString As String = String.Join(",", oWrapped)
             Dim oCriterium As String = $"[{oFirstColumn}] IN ({oValueString})"
             View.ActiveFilterCriteria = DevExpress.Data.Filtering.CriteriaOperator.Parse(oCriterium)