Example vtk/actor_picker2.py seems broken "JS Error => TypeError: t.observe is not a function"

[bourdaisj]

Reproducing

Steps:

• Create python venv. Tested with Python 3.13.7 on my linux/firefox
• pip install as per the README instructions
• run the example
  Then

python -m venv .venv
pip install "trame-vtklocal[vtk]"
python examples/vtk/actor_picker2.py

Results

The view load and is interactive, but the picking does not seems to work.
Python console: JS Error => TypeError: t.observe is not a function
Full browser console log:
console-export-trame-vtklocal-actor2picker.log

Any tips/ideas @jourdain @jspanchu ?

[bourdaisj]

The example vtk/actor_picker.py works as expected though.

[jourdain]

that's expected as the vtk version from [vtk] optional dependency is too old to have the method call and observers. (I think)

[bourdaisj]

I have exactly the same error if I run it using VTK==9.5.2

[jourdain]

Did you try nightly?

[jourdain]

9.5.2 is still missing features

[bourdaisj]

Just saw the requirements.txt file in example/vtk
I guess that'll fix it. I'll test again and update/create appropriate doc

[bourdaisj]

Works! My bad and thanks.
Getting an error though:
JS Error => 2025-11-03 11:16:17.294 ( 0.003s) [ 5DF824] vtkSession.cxx:290 ERR| Object null at id=1is not a vtkRenderWindow!

I'll update doc/readme soon