Interactive Jupyter Widgets not working in Jupyter Lab

Question

I noticed that interactive widgets are not working in my Jupyter Lab notebooks.

The following code should produce an interactive slider but doesn't:

from ipywidgets import interact, interactive, fixed, interact_manual
import ipywidgets as widgets

def f(x):
    return x

interact(f, x=10);

What is the problem here, and how can I get widgets to work?

Answer 1

You need to install widget extension

pip install ipywidgets
jupyter nbextension enable --py widgetsnbextension --sys-prefix

Answer 2

Per the docs :

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

jupyter labextension install @jupyter-widgets/jupyterlab-manager

I think it's the latter nodejs requirement that you are missing eg with Conda, first run:

conda install nodejs