Colouring columns - 2nd colour only renders on application close.

Using Streamlit
1

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  1. Are you running your app locally or is it deployed?
    Locally, using MS Edge browser

MWE below

import pandas as pd
import streamlit as st

df = pd.DataFrame({'A':[1,2,3,4], 'B':['a','b','c','d'], 'C':['foo','bar','qux', 'baz']})

def apply_style(df, fixed_cols, required_cols):
    styles = pd.DataFrame('', index=df.index, columns=df.columns)
    for col in df.columns:
        for idx in df.index:
            if col in fixed_cols:
                styles.loc[idx,col] = 'background-color: lightgrey'
            elif col in required_cols:
                styles.loc[idx,col] = 'background-color: lightsalmon'
            else:
                styles.loc[idx,col] = ''
    print(styles)
    return styles


df_styled = df.style.apply(lambda df: apply_style(df, ['A'], ['C']), axis=None)

st.data_editor(
    df_styled,
    hide_index=True,
    column_config={'C': st.column_config.TextColumn('C', required=True)},
    disabled=('A'),
    num_rows='dynamic'
    )

There is no error message or warning. Column C is not being coloured, but column A is.

When the application is stopped, column C colouring is rendered.

st_color_cols

Appreciate any advice on this, thank you :slight_smile:

  1. Share the Streamlit and Python versions.
    python - 3.12
    streamlit - 1.45.0
    pandas - 2.2.3
2

solved, thank you :slight_smile: