Fix bug launching plate viewer without ultrack

[ieivanov]

Fixes #23

Optional next step: leave out the Single-cell features widget from the napari-iohub plugin menu if ultrack is not installed (I don't actually know how to do that). We still get an error if the user clicks on Single-cell features when ultrack is not installed. The error is meaningful: RuntimeError: Failed to import command at 'napari_iohub._view_tracks:open_image_and_tracks': No module named 'ultrack' so I'm OK if we leave it as is.

[ziw-liu]

How about handling the import in _view_tracks.py? I think just moving this line inside the magicgui function will do:

napari-iohub/src/napari_iohub/_view_tracks.py

Line 9 in 80b82f8

from ultrack.reader.napari_reader import read_csv

[ziw-liu]

The napari GUI command is declared in the YAML manifest so I'm not sure if it's possible to mask out at runtime.

[ieivanov]

How about handling the import in _view_tracks.py? I think just moving this line inside the magicgui function will do:

Good point, just implemented that with an ImportError that tells the user to install napari-iohub[clustering]

I agree that it seems hard to mask out the Single-cell features widget.

Do you know why the tests fails? Seems like a problem with tox?

[ziw-liu]

Thanks!