Ipywidgets with Google Colaboratory

Question

I am trying to use ipywidgets with Google Colaboratory, and (as with plotly) the simplest example from the docs does not work. The code below shows a slider in a local notebook but only returns 10 and <function __main__.f> in a Google notebook.

!pip install ipywidgets

from ipywidgets import interact

def f(x):
  return x

interact(f, x=10)

Is there another custom initialization that I could use to enable the widgets?

Answer 1

Update: core ipywidgets now work in Colab! In particular, the base, controls, FileUpload, Image, and output widgets all work in colab. Third-party widgets still do not work.

(Tweaked original answer): ipywidgets don't Just Work with Colab: we have a different security model, wherein each output is in its own iframe (with a different origin than the main Colab page). This prevents ipywidgets from working without changes on the Colab side.