Tabulator: setting header_filters not taking effect.

[dwr-psandhu]

ALL software version info

panel 1.6.0

Description of expected behavior and the observed behavior

Moving from discourse discussion Tabulator has a header_filters that is typically set on init and that works once the table is displayed. If the header_filters are changed after the table is displayed the change doesn’t take effect. See example below

#%% show that header filters are not working
import panel as pn
pn.extension('tabulator')

# create a dataframe
import pandas as pd
df = pd.DataFrame({
    'A': [1, 2, 3, 4],
    'B': ['a', 'b', 'c', 'd'],
    'C': [True, False, True, False]
})
# header filters
header_filters = { 
    'A': {'type': 'input', 'func': 'like', 'placeholder': 'Filter A'},
    'B': {'type': 'input', 'func': 'like', 'placeholder': 'Filter B'},
    'C': {'type': 'input', 'func': 'like', 'placeholder': 'Filter C'}
}
header_filters_regex = {
    'A': {'type': 'input', 'func': 'regex', 'placeholder': 'Filter A'},
    'B': {'type': 'input', 'func': 'regex', 'placeholder': 'Filter B'},
    'C': {'type': 'input', 'func': 'regex', 'placeholder': 'Filter C'}
}
# create a tabulator table with header filters
table = pn.widgets.Tabulator(df, header_filters=header_filters, width=400, height=300)
# display the table
table.show()
# %%
table.header_filters = header_filters_regex

The table displayed initially has func like matches but then it is assigned the regex filters after show and those dont take affect.

Reloading the displayed page does make it take affect.

[holovizbot]

This issue has been mentioned on HoloViz Discourse. There might be relevant details there:

https://discourse.holoviz.org/t/tabulator-header-filters-change-after-display-not-working/8788/3

[hoxbro]

show blocks the rest of the code from running.

Can you try with servable and a button which updates the filter?

[dwr-psandhu]

@hoxbro i added a checkbox to toggle. it only works if the app is reloaded after checking the box.

# %% show that header filters are not working
import panel as pn

pn.extension("tabulator")

# create a dataframe
import pandas as pd

df = pd.DataFrame(
    {"A": [1, 2, 3, 4], "B": ["a", "b", "c", "d"], "C": [True, False, True, False]}
)
# header filters
header_filters = {
    "A": {"type": "input", "func": "like", "placeholder": "Filter A"},
    "B": {"type": "input", "func": "like", "placeholder": "Filter B"},
    "C": {"type": "input", "func": "like", "placeholder": "Filter C"},
}
header_filters_regex = {
    "A": {"type": "input", "func": "regex", "placeholder": "Filter A"},
    "B": {"type": "input", "func": "regex", "placeholder": "Filter B"},
    "C": {"type": "input", "func": "regex", "placeholder": "Filter C"},
}
# create a tabulator table with header filters
table = pn.widgets.Tabulator(df, header_filters=header_filters, width=800, height=300)

# Create a checkbox to toggle between filter types
use_regex = pn.widgets.Checkbox(name="Use Regex Filters", value=False)


# Define a callback function to update the header filters when the checkbox changes
def update_filters(event):
    if event.new:
        table.header_filters = header_filters_regex
    else:
        table.header_filters = header_filters


# Link the checkbox value to the update function
use_regex.param.watch(update_filters, "value")

# display the table and the checkbox
pn.Column(use_regex, table).show()

[dwr-psandhu]

Screenshot recording of above code in action

[hoxbro]

Can you try with servable and panel serve?

[dwr-psandhu]

I changed the last line to .servable() and tried with panel serve. Same exact behavior as in the screenshot recording

[dwr-psandhu]

https://github.com/holoviz/panel/blob/85150c61547c44a070d68ba0ab9c34b4e93ee2d5/panel/widgets/tables.py#L598

Why would this be unsupported? I guess a recent change trying to sync backend dataframe with the tabulator view. Could this be added?