No Dash dislay in JupyterLab

Dash Python
1

I know that this topic has already appeared here and in other places. I tried to follow couple paths and can not make JupyterLab to display dash apps.

Probably there is some switch I need to turn on but can’t find out what it is and have no idea where else to look. Need some help, please.

Here is how I installed test environment

conda create --name env4 python=3.8 scipy pandas jupyterlab numpy "ipywidgets=7.5" matplotlib dash
conda activate env4
conda install -c conda-forge -c plotly jupyter-dash
ipython kernel install --user --name=env4
jupyter labextension install @jupyter-widgets/jupyterlab-manager plotlywidget@4.12.0
jupyter labextension install jupyterlab-plotly@4.12.0
conda install -c plotly plotly=4.12.0

(last command is there because v4.11 is loaded natively by conda).

Here is my JupyterLab extension list:

        @jupyter-widgets/jupyterlab-manager v2.0.0  enabled  OK
        jupyterlab-dash v0.3.0  enabled  OK
        jupyterlab-plotly v4.12.0  enabled  OK
        plotlywidget v4.12.0  enabled  OK

Here is some code from Dash website as an example of what I can’t display in JupyterLab.

import plotly.graph_objects as go # or plotly.express as px
fig = go.Figure() # or any Plotly Express function e.g. px.bar(...)
# fig.add_trace( ... )
# fig.update_layout( ... )

import dash
import dash_core_components as dcc
import dash_html_components as html
from jupyter_dash import JupyterDash

app = JupyterDash(__name__)

# app = dash.Dash()
app.layout = html.Div([
    dcc.Graph(figure=fig)
])

app.run_server(mode='jupyterlab', port = 8090, dev_tools_ui=True, #debug=True,
          dev_tools_hot_reload =True, threaded=True)

it opens new tab in JupyterLab but tab is blank.
The same when I use mode = inline
but
mode=external produces new tab in browser, as it should.

Sorry for so many words but I’m bit frustrated that I can’t make it work.
At the same time Plotly graphs are displayed properly.
As said, I’ve tried different combinations and none seems to work. Need some ideas what to do. pls.

2

The most likely cause for above is user.js configuration for my browser.

3

@Marcas did you end up solving the issue?

4

Not in details, I had not enough time. I use web browser with tweaked settings, one of those must prevent JupLab from rendering Dash inline (I messed up with that lately for a while). When I use default profile everything seems to be fine, so I assume one or few of browser’s settings are responsible. I can work with external mode of JupyterDash, no problem. Now, when I know where to look if I need to fix that issue I can work more relaxed :slight_smile:

Other issue is still mystery, but this in another post (initial_callbacks).

thanks

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