UIBarButtonItem have identifiers like Cancel, Done and some others. They are shown as text to user. If user changes language then for example Cancel button will be translated automatically. And as developer you do not need to provide localization string for this buttons. It means that Cancel, Done and other strings already localized and comes together with OS. UIBarButtonItem have identifiers like Cancel, D
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如何获得本地化取消，完成等？
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