public final class MediaItemView: NSView {
 
   public override init(frame frameRect: NSRect) {
      super.init(frame: frameRect)
 
      // error: 'NSFilenamesPboardType' is unavailable in Swift:
      // use 'NSPasteboard.writeObjects(_:)' with file URLs
      let draggedTypes: [NSPasteboard.PasteboardType] = [NSFilenamesPboardType]
      registerForDraggedTypes(draggedTypes)
   }
}

什么是Swift4中NSFilenamesPboardType的替代品？如何在Swift4中注册拖动类型的文件名(在我的情况下是mp3,wav,aiff,…文件)？

谢谢！