Could not get the correct file mimeType

[leoelephant]

onDragDone: (detail) async { setState(() { list.addAll(detail.files); }); for (final file in detail.files) { debugPrint(file.mimeType); } },

Then the console prints out null。 done: D:\XXX.jpg flutter: null

What should I do to get the correct file type？ thx