JupyterLab Setup is unclear

Problem

Hi! I had a hard time to understand what is actually necessary to install when using ipywidgets in JupyterLab. I tried following the documentation here: https://ipywidgets.readthedocs.io/en/latest/user_install.html

And eventually I was successful by putting ipywidgets and nodejs into my requirements.txt file and then enabling then installing the lab extension jupyter labextension install @jupyter-widgets/jupyterlab-manager.

However, it was unclear which things apply to my setup. The first line in “Installing the JupyterLab Extension” says:

To install the JupyterLab extension you also need to run the command below in a terminal which requires that you have nodejs installed.

“Also”, also to what? The headlines are all on the same level, so the JupyterLab instructions are not a subsection of something that was already installed.

Some of my thoughts:

• The instruction for Jupyterlab uses conda, but the conda section above says in enables the extension already.
• Do i need the widgetsnbextension too?
• Do I actually have to install ipywidgets if I install the extension?

I was additionally confused by this Binder example that I eventually discarded: https://github.com/binder-examples/jupyter-extension/

Proposed Solution

I would suggest to either restructure to add some hierarchy to see what builds on top of what. or make the section self contained such that you only need to follow that are there.

[keckelt]

okay,thanks. I’ll then close this again. Looking forward to v3 🙂

[martinRenou]

I understand the instructions can be confusing, we get lots of reports from people who could not follow the installations steps properly and en up with broken JupyterLab installation. But again, this should be simplified with the new extension system in JupyterLab 3.

Soon, you’ll only need to run pip install ipywidgets or conda install -c conda-forge ipywidgets.