Page rerunning even after using session state and st.form

[DeeTherese]

Hi, this is my code and the image is what the page looks like, but when submitting the form in the third expander section the whole page reruns.

# Select and Download revisions to the data
                def apply_changes(data, convert_dtypes, apply_deduplication, apply_numeric_extraction, apply_outlier_replacement, labs_outlier_thresholds):
                    if convert_dtypes:
                        data = validate_and_convert_dtypes(TABLE, data)[0]
                    
                    if apply_deduplication:
                        data = data.drop_duplicates()

                    if apply_numeric_extraction:
                        col = data['lab_value'].astype(str)
                        data['lab_value_numeric'] = pd.to_numeric(col.str.extract('(\d+\.?\d*)', expand=False), errors='coerce')    

                    if apply_outlier_replacement:
                        data, _, _, _ = replace_outliers_with_na_long(data, labs_outlier_thresholds, 'lab_category', ‘lab_value_numeric’)

                    return data


                def convert_df_to_file_format(data, file_format):
                    if file_format == ‘csv’:
                        return data.to_csv(index=False).encode('utf-8’)
                    elif file_format == ‘parquet’:
                        return data.to_parquet(index=False)
                    else:
                        return None
                
                st.write("# Select and Download Recommended Revisions to the Data”)
                with st.expander("Expand to View”):
                    st.write("#### Select changes to apply”)

                    if 'form_submitted' not in st.session_state:
                        st.session_state['form_submitted'] = False

                    with st.form(key='apply_labs_changes_form’):
                        # Create checkboxes for changes
                        if any(data.duplicated()):
                            apply_deduplication = st.checkbox("Remove duplicates”)
                        else:
                            apply_deduplication = False

                        if create_lab_value_numeric:
                            apply_numeric_extraction = st.checkbox("Create 'lab_value_numeric’”)
                        else:
                            apply_numeric_extraction = False

                        if replaced_count > 0:
                            apply_outlier_replacement = st.checkbox("Replace outliers”)
                        else:
                            apply_outlier_replacement = False

                        if mismatch_columns:
                            convert_dtypes = st.checkbox("Convert to expected data types”)
                        else:
                            convert_dtypes = False
                
                        st.write("#### Select file format for download”)
                        file_type = st.selectbox("Select file type for download", ["csv", "parquet”])
                        submit_button = st.form_submit_button(label=‘Submit’)

                    if submit_button:
                        st.session_state['form_submitted'] = True

                    if st.session_state['form_submitted’]:
                        with st.spinner("Applying changes…”):
                            df = data.copy()
                            revised_data = apply_changes(df, convert_dtypes, apply_deduplication, apply_numeric_extraction, apply_outlier_replacement, labs_outlier_thresholds)
                            revised_data_file = convert_df_to_file_format(revised_data, file_type)
                            st.write("Successfully applied changes. Click to download revised data.”)
                        if revised_data_file:
                            st.download_button(
                                label="Download revised data”,
                                data=revised_data_file,
                                file_name=f"revised_{TABLE}_data.{file_type}”,
                            )
                        if st.button("Reset”):
                            st.session_state['form_submitted'] = False

[Goyo]

@DeeTherese

when submitting the form […] the whole page reruns

That is how it is supposed to work.