[BUG] CheckboxGroup minimal example in the documentation (Widgets and DOM elements 3.0.3) does not work properly

[santelelle]

Software versions

Python version : 3.9.5 (default, Jun 4 2021, 12:28:51)
IPython version : (not installed)
Tornado version : 6.1
Bokeh version : 3.0.3
BokehJS static path : /home/lele/.conda/envs/py3.9-torch1.9-opencv/lib/python3.9/site-packages/bokeh/server/static
node.js version : v16.19.0
npm version : 8.19.2
Operating system : Linux-6.1.1-arch1-1-x86_64-with-glibc2.36

Browser name and version

Chrome Version 108.0.5359.124 (Official Build) (64-bit)

Jupyter notebook / Jupyter Lab version

No response

Expected behavior

Nothing is written in the browser console when changing the status of the CheckboxGroup (The callback seems to be not triggered).

Other example codes (i.e. the Switch) properly print in the browser console.

Observed behavior

Nothing happens.

Example code

from bokeh.io import show
from bokeh.models import CheckboxGroup, CustomJS

LABELS = ["Option 1", "Option 2", "Option 3"]

checkbox_group = CheckboxGroup(labels=LABELS, active=[0, 1])
checkbox_group.js_on_event('button_click', CustomJS(code="""
    console.log('checkbox_group: active=' + this.origin.active, this.toString())
"""))

show(checkbox_group)

Stack traceback or browser console output

No response

Screenshots

No response

[bryevdv]

This code works:

checkbox_group.js_on_change('active', CustomJS(code="""
    console.log('checkbox_group: active=' + this.active, this.toString())
"""))

and as far as I know is what the code should actually be in the docs. @mattpap can you comment?

[bryevdv]

The RadioGroup example is broken in exactly the same way

https://docs.bokeh.org/en/latest/docs/user_guide/interaction/widgets.html#radiogroup

[bryevdv]

I've tentatively triaged this as a docs bug, though perhaps some version of a button event is also supposed to function.