基于Streamlit会话状态解决复选框切换时数据编辑器值重置问题

Step 1: Initialize Session State with Default DataFrame #

Store the initial DataFrame in st.session_state to preserve its values across app reruns, preventing the Value column from resetting when checkboxes are toggled.

import streamlit as st
import pandas as pd

# Initialize session state DataFrame if it doesn't exist
if 'df' not in st.session_state:
    st.session_state.df = pd.DataFrame(
        data={'Value': [0, 0, 0, 0], 'Active': [False, False, False, False]},
        index=['A', 'B', 'C', 'D']
    )

Step 2: Create Checkboxes to Toggle Active Status #

Generate checkboxes for each key (A-D) and sync their state with the Active column in the session state DataFrame.

# Create checkboxes for each index and update Active status
for idx in st.session_state.df.index:
    current_active = st.session_state.df.loc[idx, 'Active']
    new_active = st.checkbox(f"Activate {idx}", value=current_active)
    st.session_state.df.loc[idx, 'Active'] = new_active

Step 3: Filter and Edit Active Rows #

Filter the DataFrame to show only rows where Active is True, then use st.data_editor to let users modify the Value column. Update the session state DataFrame with edited values to preserve changes.

# Filter to get active rows (only Value column)
active_rows = st.session_state.df[st.session_state.df['Active']][['Value']]

# Let user edit the active rows' values
edited_values = st.data_editor(active_rows, num_rows="fixed")

# Update the session state DataFrame with edited values
st.session_state.df.update(edited_values)

Full Working Code #

Combining all parts, here's the complete script:

import streamlit as st
import pandas as pd

# Initialize session state DataFrame
if 'df' not in st.session_state:
    st.session_state.df = pd.DataFrame(
        data={'Value': [0, 0, 0, 0], 'Active': [False, False, False, False]},
        index=['A', 'B', 'C', 'D']
    )

# Checkboxes to toggle Active status
for idx in st.session_state.df.index:
    current_active = st.session_state.df.loc[idx, 'Active']
    new_active = st.checkbox(f"Activate {idx}", value=current_active)
    st.session_state.df.loc[idx, 'Active'] = new_active

# Filter active rows and allow editing
active_rows = st.session_state.df[st.session_state.df['Active']][['Value']]
edited_values = st.data_editor(active_rows, num_rows="fixed")
st.session_state.df.update(edited_values)

# Optional: Display full DataFrame for verification
st.subheader("Full DataFrame (for verification)")
st.dataframe(st.session_state.df)

How It Works #

• Session State Storage: The DataFrame is saved in st.session_state, so its values are retained between reruns triggered by checkbox clicks.
• Checkbox Sync: Each checkbox's state is linked directly to the Active column in the session state DataFrame, ensuring toggles update the DataFrame immediately.
• Preserving Edits: When users modify values in st.data_editor, the edited data is merged back into the session state DataFrame using update(), so changes persist even when other checkboxes are toggled.

内容的提问来源于stack exchange，提问作者Davi Augusto Bandeira