Access edited data from st.data_editor

šŸ§© Streamlit Components
1

I have a streamlit app where I am showing a Pandas dataframe as a editable dataframe using the st.data_editor component.

I am able to edit the values in the table shown using st.data_editor. However I want to access that edited data in my code for further reference.

I am able to get the index of which rows were edited using the edited _rows parmater but not able to access the actual updated data.

Can anyone please help me in how to achieve this functionality?

2

Not sure what you are looking for exactly. edited_rows is a dictionary and you acces it like any other dictionary. All the data is there as you can see in the example application.

3

@Gayo

I want to achieve the functionality that is shown here in this demo app.

The issue that I am facing now is that when I change the values in the table that I am displaying using st.data_editor, the entire page reloads for every entry that I change.

Firstly, I want to reload it only after hitting a ā€œSaveā€ button. Second, I donā€™t want all my other components in my app to reload. Just the table should reload.

4

What functionality shown there are you unable to achieve?

I am not sure I understand what you mean by ā€œreloadā€. Your script runs again each time the user interacts with a widget, as explained in the docs:

any time something must be updated on the screen, Streamlit reruns your entire Python script from top to bottom.

This can happen in two situations:

  • Whenever you modify your appā€™s source code.

  • Whenever a user interacts with widgets in the app. For example, when dragging a slider, entering text in an input box, or clicking a button.

You can avoid the rerun by putting some widgets in a form. But changes made to those widgets wonā€™t be available to the application until the submit button is clicked. There is an example of that in the demo you linked.

5

Thanks @Goyo for the response. I have put my data editor component inside a form and now the page reloads only after clicking the form button.The ā€œRecalculate and saveā€ button in the form recalculates everything based on the edited data and saves it in the session_state variable.

However, the recalculations are visble after clicking the button twice.

I am attaching my code for reference.

Please let me know where I am going wrong or if there is any other way to achieve the same.
Also let me know which all blocks to cache and how. I have not familiar with caching in Streamlit.

import streamlit as st

session_state = st.session_state


dropdown = # code for st.selectbox()



if dropdown:
    df= pd.read_csv("filename.csv")

    #some extra preprocessing and function calls

    df = some_preprocess(df)

    grouped_df = df.groupby("Group").agg({"column_1":"sum"})

    grouped_df["col2"]=1



    if "original_data" not in session_state:
        session_state.original_data= grouped_df

    if "edited_data" not in st.session_state:
        session_state.edited_data= grouped_df.copy()
    

    def save_edits():

        edited_df = session_state.edited_data

        #recalculation of col2 based on edits made in the table
        edited_df["col2"] = edited_df["col1"]+3

        session_state.edited_data=edited_df
        session_state.original_data=session_state.edited_data
    

    with st.form("Table"):
        session_state.edited_data = st.data_editor(session_state.original_data,num_rows="dynamic")

        st.form_submit_button("Recalculate and save",on_click=save_edits)
6

The return value of the widgets in a form is only available in the next rerun, after calling the callback. In the callback, session_state.edited_data still has the old data, you cannot access the edited data from there.