Support Tabulator scrollToRow

[douglas-raillard-arm]

Is your feature request related to a problem? Please describe.

Being able to scroll inside the table programmatically is very useful when linking plots with custom interactivity with some tabular data.

Describe the solution you'd like

An API allowing to scroll to the given row, and possibly linked to a stream so that a holoviews plot X position can scroll directly in a table displayed under it.

Tabulator seems to already have support for scrolling programmatically:
http://tabulator.info/docs/4.1/navigation#scroll-row

Describe alternatives you've considered

pn.widgets.DataFrame() automatically scrolls when its "selection" attribute is modified. It would be nice to have a similar behavior for Tabulator.

EDIT: add alternative

[philippjfr]

I'm out on vacation this week but will work a little bit on Thursday to release Panel 0.12. If a PR to implement this were to magically appear before then I'd happily merge it and get it into this release :)

[douglas-raillard-arm]

First time I touch Javascript in ~14 years but I'll give that a shot, I guess it should not be too hard :)

[douglas-raillard-arm]

So as a starter I was contemplating scrolling to the currently selected row, like pn.widgets.DataFrame. I tried this:

import panel as pn
pn.extension('tabulator')
import pandas as pd

df = pd.DataFrame(dict(a=[1,2], b=[3,4]))
df = pd.concat([df]*10)
df = df.reset_index(drop=True)

table = pn.widgets.Tabulator(df, height=100)
table

# Experiment with jscallback to see how it works
value1 =   pn.widgets.Spinner(value=0, width=75)
result =   pn.widgets.StaticText(value='0', width=50, align='center')

value1.jscallback(value="""
  result.text = v1.value.toString()
""", args={'result': result, 'v1': value1, 'thetb': table})

pn.Row(value1, result)

In the little experiment with jscallback, everything works well, until I add 'thetb': table to the args dict. I tried some console.log() to no avail. It looks like that binding the Tabulator widget to a callback like that breaks the callback, which never fires.

Any idea on what is happening ?