Add simple nested editor to Tabulator

[hoxbro]

Screencast.2024-09-10.18.57.55.mp4

import pandas as pd
import panel as pn

pn.extension("tabulator")

df = pd.DataFrame({"0": ["A", "B", "A"], "1": [1, 2, 3], "2": [None, None, None]})

options = {
    "A": [1, 2, 3, 4, 5],
    "B": {
        "1": list(range(5, 10)),
        "2": list(range(10, 15)),
        "3": list(range(15, 20)),
    },
}
tabulator_editors = {
    "0": {"type": "list", "values": ["A", "B"]},
    "1": {"type": "list", "values": [1, 2, 3]},
    "2": {"type": "nested", "options": options, "lookup_order": ["0", "1"]},
}

def on_edit(event):
    if event.column in ("0", "1"):
        edit_table.patch({"2": [(event.row, None)]})

edit_table = pn.widgets.Tabulator(df, editors=tabulator_editors, show_index=False, on_edit=on_edit)

edit_table

[codecov]

Codecov Report

Attention: Patch coverage is 41.66667% with 14 lines in your changes missing coverage. Please review.

Project coverage is 82.23%. Comparing base (0453e9c) to head (81389c8).
Report is 10 commits behind head on main.

Files with missing lines	Patch %	Lines
panel/tests/ui/widgets/test_tabulator.py	41.66%	14 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7251      +/-   ##
==========================================
- Coverage   82.23%   82.23%   -0.01%     
==========================================
  Files         337      337              
  Lines       50251    50317      +66     
==========================================
+ Hits        41325    41379      +54     
- Misses       8926     8938      +12     

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[philippjfr]

What happens if there is no entry here? Does it handle it gracefully?

[hoxbro]

It handled it by not showing up anything. I have pushed a change so it now will show:

(not using the same example as the post)

[philippjfr]

Asked on clarifying question, otherwise this looks great!

[MarcSkovMadsen]

This is an alternative example in an attempt to make it more clear which columns contains the nested selections and how the options depends on the selections in other columns. Its also more verbose, so its not clear to me if I should contribute this as and improvement to the docs. Thus I just persist it here for now.

nested-selections.mp4

import pandas as pd
import panel as pn

pn.extension("tabulator")

df = pd.DataFrame({"0": ["A", "B", "A"], "1": [1, 2, 3], "Nested Selection": [None, None, None]})

options = {
    "A": ["A.1", "A.2", "A.3", "A.4", "A.5"],
    "B": {
        "1": ["B1.1", "B1.2", "B1.3"],
        "2": ["B2.1", "B2.2", "B2.3"],
        "3": ["B3.1", "B3.2", "B3.3"],
    },
}
tabulator_editors = {
    "0": {"type": "list", "values": ["A", "B"]},
    "1": {"type": "list", "values": [1, 2, 3]},
    "Nested Selection": {"type": "nested", "options": options, "lookup_order": ["0", "1"]},
}


def on_edit(event):
    if event.column in ("0", "1"):
        edit_table.patch({"Nested Selection": [(event.row, None)]})


edit_table = pn.widgets.Tabulator(df, editors=tabulator_editors, show_index=False, on_edit=on_edit)

edit_table.servable()

[hoxbro]

I think it is a better example, so you are welcome to open a PR with your suggested changes.