SlicerTrame server does not start

[lassoan]

After clicking "Start Server" in SlicerTrameServer module, I get the following error and the server does not start:

qSlicerMarkupsModulePrivate::addToolBar: no main window is available, toolbar is not added

qSlicerSequencesModulePrivate::addToolBar: no main window is available, toolbar is not added

Loading Slicer RC file [C:/Users/andra/.slicerrc.py]

Traceback (most recent call last):
  File "<string>", line 5, in <module>
  File "<string>", line 10, in <module>
  File "C:\D/trame-slicer/examples\widgets\__init__.py", line 7, in <module>

    from .tools_strip import ToolsStrip
  File "C:\D/trame-slicer/examples\widgets\tools_strip.py", line 11, in <module>
    from .segmentation_button import SegmentationButton
  File "C:\D/trame-slicer/examples\widgets\segmentation_button.py", line 22, in <module>
    from trame_slicer.segmentation import (
ImportError: cannot import name 'SegmentationEffectID' from 'trame_slicer.segmentation' (C:\Users\andra\AppData\Local\slicer.org\3D Slicer 5.11.0-2025-12-09\lib\Python\Lib\site-packages\trame_slicer\segmentation\__init__.py). Did you mean: 'SegmentationEffect'?

The same happened when I tried with Slicer-5.10.

[Thibault-Pelletier]

Hi @lassoan,

This error is likely due to running an outdated example from the server.

The path to the latest used server is kept in the UI.
You should update your local installed version and point to the matching downloaded example if you want the latest examples.

For instance :

• downloaded_examples/v1.7.1/medical_viewer_app.py
• downloaded_examples/v1.7.1/segmentation_app.py

Note that the v1.7.0 examples don't work in Slicer trame due to bad import definition (we are missing a CI tests to catch runtime compatibility between the two environments in the trame-slicer repo...)

EDIT: on my install, the full path resolves to :
C:/Users/Thibault/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.1/segmentation_app.py

In SlicerTrame, I think we will reset the default script path if it's pointing to a downloaded to an example to avoid this type of problems in the future when bumping version.

[rachellh123]

I am having a very similar issue. I get:

qSlicerSequencesModulePrivate::addToolBar: no main window is available, toolbar is not added

Traceback (most recent call last):
  File "<string>", line 6, in <module>
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\__init__.py", line 1, in <module>

    from .logic import MedicalViewerLogic, SegmentationAppLogic
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\logic\__init__.py", line 2, in <module>
    from .load_volume_logic import LoadVolumeLogic
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\logic\load_volume_logic.py", line 10, in <module>
    from ..ui import (
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\ui\__init__.py", line 9, in <module>
    from .medical_viewer_ui import MedicalViewerUI
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\ui\medical_viewer_ui.py", line 12, in <module>
    from .segmentation import (
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\ui\segmentation\__init__.py", line 8, in <module>
    from .segment_editor_ui import (
  File "C:\Users/AppData/Local/slicer.org/3D Slicer 5.10.0/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.0\viewer_lib\ui\segmentation\segment_editor_ui.py", line 18, in <module>
    from examples.viewer_lib.ui.viewer_layout import ViewerLayoutState

ModuleNotFoundError: No module named 'examples'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<string>", line 5, in <module>
  File "<string>", line 8, in <module>
ImportError: attempted relative import with no known parent package

I have 3D Slicer v 5.10.0, Python 3.13 and Windows 11 and I downloaded the scripts Monday so they should be the latest. I have tried running with both standard permissions and elevated 'Admin' permissions.

[lassoan]

This error is likely due to running an outdated example from the server.

Thank you @Thibault-Pelletier, this solved the issue! With the C:/tmp/Slicer 5.10.0 trame/slicer.org/Extensions-34045/SlicerTrame/lib/Slicer-5.10/qt-scripted-modules/Resources/downloaded_examples/v1.7.1/medical_viewer_app.py script SlicerTrame started successfully!

@rachellh123 it seems that you are using downloaded_examples/v1.7.0 and according to @Thibault-Pelletier comment above, you need v1.7.1.

@Thibault-Pelletier I haven't closed this issue in case you want to keep it open as a reminder to make this more foolproof. It should be easier to select scripts from the Examples and downloaded_examples folders. It would be also nice to give the user some hint that he uses an older example script.

[Thibault-Pelletier]

@lassoan thanks for the update, happy that it's now resolved!

Yes, please leave this issue open.
I will work on making running the examples easier and list the different application examples (probably following what is done in the Sample Data module)

@rachellh123, as mentioned by @lassoan, version v1.7.0 examples are broken in Slicer trame. You can update your library version to 1.7.1 using the update button and change the path to the 1.7.1 examples and it should work.

Further information on the fix in the commit (i.e., dumb import problem...) .

[rachellh123]

Thanks that resolved the issue for me as well. The dropdown did not switch to the new version when the update installed so it was easy to miss

[Thibault-Pelletier]

Thx @rachellh123 for the feedback!
Definitely something we will improve on for future versions!