I simple run this code in a jupyter notebook/lab cell:

from ipycanvas import Canvas
from ipywidgets import Button
from IPython.display import display

WIDTH = 200  # px
HEIGHT = 200  # px

# Create a canvas 700x250 pixels with a black border
canvas = Canvas(width=WIDTH, height=HEIGHT)

# Add black border around the canvas
canvas.stroke_style = 'black'
canvas.stroke_rect(0, 0, WIDTH, HEIGHT)

# List to store clicked positions
clicked_positions = []

# Function to handle clicks and draw red dots
def handle_click(x, y):
    # Add the clicked position to the list
    clicked_positions.append((x, y))
    # Draw a red dot with radius 3 at the clicked position
    canvas.fill_style = 'red'
    canvas.fill_circle(x, y, 3)

# Attach the click event handler to the canvas
canvas.on_mouse_down(lambda x, y: handle_click(x, y))

# Button to display clicked positions
show_button = Button(description="Show clicked positions")

# Function to display the clicked positions
def show_positions(b):
    print("Clicked positions:", clicked_positions)

show_button.on_click(show_positions)

# Display the canvas and button
display(canvas, show_button)

IT WORKS!

Now I want to run it in a reveal.js/jupyterlab_rise/rise slideshow

And this is where all the madness starts, so I won’t put any of the dozens of issues I experienced in here.

I will just state, that the best outcome, of actually seeing and being able to click onto the canvas within the presentation I only had when installing:

python3.12 -m pip install notebook==6.5.4 ipywidgets==8.1.5 ipycanvas==0.11.0 rise==5.7.1

So in the end it looks like this:

>> python3.12 -m jupyter --version

Selected Jupyter core packages...
IPython          : 8.10.0
ipykernel        : 6.29.5
ipywidgets       : 8.1.5
jupyter_client   : 8.6.2
jupyter_core     : 5.7.2
jupyter_server   : 2.14.2
jupyterlab       : not installed
nbclient         : 0.10.0
nbconvert        : 7.16.4
nbformat         : 5.10.4
notebook         : 6.5.4
qtconsole        : not installed
traitlets        : 5.9.0

But also this version crashs after setting a few dots onto the canvas.

ANY HELP is greatly appreciated!
Meaning: – I need a canvas, which I can draw on to retrieve the coordinates to the next cell AND I want to do it inside a reveal.js – presentation using jupyter.

If someone has a working version of jupyter notebook/lab using ipywidgets + reaveal.js and could document its version this would be super helpful, since I already tested a lot of combinations without success -> especially version 4.x.x seem to break a lot of extension codes?! I also wouldn’t know for which jupyter version the extension developer created its release eg. ipywidgets?!?