Can't reset selected items (check box, radio buttons) by clearing session.state

[sachinpatel248]

Summary

Can not clear existing selected items from check box, radio buttons.
Tried to reset my selection by deleting each element in streamlit.session.state

Is there any workaround to achieve this?

Steps to reproduce

Code snippet:

import streamlit as st
from streamlit import caching

st.set_page_config(layout="wide")

columns = st.columns(4)

columns[0].header("Session State Start")
columns[0].write(st.session_state)


n_check_box = 3
columns[1].header("Sample CheckBox")
for i in range(n_check_box):
    label = "check_box_" + str(i + 1)
    columns[1].checkbox(label=label, value=False, key=label)


n_radio_button = 2
columns[2].header("Sample Radio Button")
for i in range(n_radio_button):
    key = "radio_button_" + str(i + 1)
    label = "Radio Selection " + str(i + 1)
    values = ["Radio " + str(n) for n in range(n_radio_button)]
    columns[2].radio(label, values, key=key)


columns[3].header("Session State End")
columns[3].write(st.session_state)


if st.button("Clear Selection", key="clear_selection_button"):
    st.subheader("Executing code")
    code_clear_session_state = """
    for key in st.session_state.keys():
        del st.session_state[key]
    caching.clear_cache()"""
    st.code(code_clear_session_state, language="python")

    for key in st.session_state.keys():
        del st.session_state[key]
    caching.clear_cache()

Steps :

1. Select any option/(s) from radio button & checkbox.
2. Click on Clear Selection button

Expected behavior:

On clicking Clear Selection all selected items should get clear/reset.

Actual behavior:

Selected data persists

Is this a regression?

Not sure

Debug info

• Streamlit version: 0.86.0
• Python version: 3.8.8
• Using: PipEnv
• OS version: Windows 10
• Browser version: Chrome 93

Additional information

Had asked this in streamlit forum https://discuss.streamlit.io/t/clearing-all-selected-items-check-box-radio-buttons-selectbox/16605

[sachinpatel248]

Hi Team,
It's almost 2 weeks, any updates here?

[sachinpatel248]

@Amey-D , @kantuni , @vdonato , @mesmith027
Any views?

[kmcgrady]

Hey @sachinpatel248 Thanks for reaching out. The team has been busy the past few weeks and is finally catching up a little bit. We are taking a look at this issue and hopefully will have a fix out soon. Stay tuned! 😊

[Dowdtw1]

Any updates/fixes/solutions put in place to enable this functionality please?

[sachinpatel248]

Not at the moment.

…

On Mon, 23 May, 2022, 7:35 pm Dowdtw1, ***@***.***> wrote: Any updates/fixes/solutions put in place to enable this functionality please? — Reply to this email directly, view it on GitHub <#3841 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACAJNQQO7XIFS34YOWRBBRTVLOGCRANCNFSM5EVFL6PQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[sfc-gh-kbregula]

Here is workaround:
#4457

ctx = get_script_run_ctx()
state_key = ctx.session_state._state._get_widget_id('checkbox')
ctx.session_state[session_key] = val

[sfc-gh-jcarroll]

I know this is a zombie issue but I was looking at it recently from the link Kamil posted above.

I wanted to report that this is intended behavior - deleting the key associated to a widget in session_state is not intended to clear or reset the widget.

Here's similar working app code that meets the intent of OP's snippet above - changing the button execution to a callback and setting the key to the expected value instead of deleting it.

import streamlit as st

st.set_page_config(layout="wide")

columns = st.columns(4)

columns[0].header("Session State Start")
columns[0].write(st.session_state)


n_check_box = 3
columns[1].header("Sample CheckBox")
for i in range(n_check_box):
    label = "check_box_" + str(i + 1)
    columns[1].checkbox(label=label, value=False, key=label)


n_radio_button = 2
columns[2].header("Sample Radio Button")
for i in range(n_radio_button):
    key = "radio_button_" + str(i + 1)
    label = "Radio Selection " + str(i + 1)
    values = ["Radio " + str(n) for n in range(n_radio_button)]
    columns[2].radio(label, values, key=key)


columns[3].header("Session State End")
columns[3].write(st.session_state)

def clear_selection():
    for key in st.session_state.keys():
        if key.startswith("radio"):
            st.session_state[key] = "Radio 0"
        elif key.startswith("check"):
            st.session_state[key] = False


st.button("Clear Selection", on_click=clear_selection)