isundoing and isredoing for NSUndoMananger is not in Swift

Question

isundoing and isredoing for NSUndoMananger is not available in OS X 10.10 or Swift。你有任何關於更換的建議嗎？

由於

Answer 1

的性質稱爲undoing和redoing在夫特：

if undoManager.undoing { } 
if undoManager.redoing { } 

參見undoing 在NSUndoMananger類參考。