' Declare an EditorWithCombo variable Private editor As EditorWithCombo = Nothing ' Handles the UltraTree control's AfterActivate event, to fire the SelectionChanged event of the EditorWithCombo associated with the ActiveNode. Private Sub ultraTree1_AfterActivate(ByVal sender As Object, ByVal e As NodeEventArgs) Handles ultraTree1. AfterActivate Dim node As UltraTreeNode = e.TreeNode If node Is Nothing Then Exit Sub End If Dim editor_Combo As EditorWithCombo = TryCast(node.EditorResolved, EditorWithCombo) ' If the editor hasn't changed since the last time we did this, return since we are already listening to the right editor's event If Me.editor = editor_Combo Then Exit Sub End If ' If we have a non-null editor reference, unhook its SelectionChanged event ' (This loop is executed if the previous selection was a different editor) If Me.editor IsNot Nothing Then RemoveHandler Me.editor.SelectionChanged, AddressOf Me.editor_SelectionChanged Me.editor = Nothing End If ' Set our reference Me.editor = editor_Combo ' Wire the event on the new editor AddHandler Me.editor.SelectionChanged, AddressOf Me.editor_SelectionChanged End Sub ' Handles the EditorWithCombo's SelectionChanged event. Private Sub editor_SelectionChanged(ByVal sender As Object, ByVal e As EventArgs) Handles editor.SelectionChanged Dim editor As EditorWithCombo = TryCast(sender, EditorWithCombo) Dim val As Object = editor.Value End Sub