private MyEdit GetEdit(OutlinerDocument document, TreeListView treeListView) { OutlinerNote note = document.FindOutlinerNoteByDocument(__DocumentGuid); Debug.Assert(note != null, "GetEdit's note == null"); TreeListViewItem item = ViewHelpers.GetContainerForItem(treeListView, note); Debug.Assert(item != null, "Bad news: UndoMyAction's Undo has item == null"); MainWindow mw = DragDropHelper.GetMainWindow(treeListView); MyEdit edit = item.GetEditor(mw.GetViewColumnId(__ColumnId), __ColumnId, __IsInlineNote); return(edit); }