     else
       @_spMinusTp = _scrollPosition - @trackingPositionFromPendingGeometry
 
-    @_updateOnScreenInfo oldChildrenOffset != @_childrenOffset
-
-  _updateOnScreenInfo: (childrenOffsetChanged)->
+    @_updateOnScreenInfo @_childrenOffset - oldChildrenOffset
+
+  _updateOnScreenInfo: (childrenOffsetDelta)->
     {isVertical, windowSize} = @
 
     focusedChild = @_pendingState._focusedChild

    firstOnScreenChildIndex = -1 if firstOnScreenChildIndex == children.length

    if (
        childrenOffsetChanged ||
        firstOnScreenChildIndex != @_firstOnScreenChildIndex ||
        lastOnScreenChildIndex  != @_lastOnScreenChildIndex ||
        focusedChildIndex       != @_focusedChildIndex ||

          @scrollRatio
          @childrenOffset
          @childrenSize
          childrenOffsetDelta
          windowSize
          focusedChild
          firstOnScreenChildIndex
