             self?.pageViewsByPageIndex = [:]
             
             self?.currentSpreadIndex = nil
-            self?.currentSpreadPageIndexes = NSIndexSet()
-            self?.visibleSpreadIndex = nil
-            self?.visibleSpreadPageIndexes = NSIndexSet()
+            self?.currentPageIndexes = NSIndexSet()
+            self?.centeredSpreadIndex = nil
+            self?.visiblePageIndexes = NSIndexSet()
             
             self?.spreadConfiguration = nil
             

        
        
        // figure out which page we should scroll to
        var targetPageIndex = visibleSpreadPageIndexes.firstIndex
        if targetPageIndex == NSNotFound {
            targetPageIndex = 0
        }

            }
            
            // calculate the spreadIndex that was centered when  we started this drag
            dragStartSpreadIndex = centeredSpreadIndex ?? 0
            dragStartVisibleRect = scrollView.bounds
            _didStartScrolling()
        }
