Session.state stopped working

Just getting into Streamlit and have successfully been using session.state to save the state of some sliders on a Streamlit page.
Worked well in 0.88. Upgraded to 1.0 today and session.state appears to have stopped working.

Can’t find any info on this in the docs. - does it need some sort of cache clear?


Hi @steeley, welcome to the community! :wave: :partying_face:

I’m sorry to hear you’re having trouble using the Session State API. It would help if you could provide a reproducible code example demonstrating this behavior.

With Streamlit 1.0, I’m able to save the state of a slider widget as a Session State variable. Every widget with a key is automatically added to Session State. To learn more, check out Session State and Widget State association


Best, :balloon:

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Thanks for the reply Snehan.

The important thing here is that I need to keep my slider values if I navigate to another streamlit page and back again.

As stated, my code has not changed - I simply updated to v 1.0 from 0.88. so that iis why I ask if the API has changed.

I tried your example as written, but it seems that the key is not automatically added, so I get an error
stating this. it only works if I do this:

import streamlit as st

if 'myslider' not in st.session_state:
        st.session_state.myslider = 0

slider = st.slider("my_slider",0,100,key="mySlider")

my original code below, worked perfectly in 0.88 , the keys are saved and my sliders are remembered if I go to another streamline page and come back again.

import streamlit as st

if 'gen_level' not in st.session_state:
        st.session_state.gen_level = 0
if 'gen_freq' not in st.session_state:
        st.session_state.gen_freq = 5
if "gen_balance" not in st.session_state:
        st.session_state.gen_balance = 0.0

st.slider('Level', min_value=0, max_value=10, key = 'gen_level')
st.write(" ")
st.slider('freq', min_value=0, max_value=10, key = 'gen_freq')
st.write(" ")
st.slider("balance", min_value=-10.0, max_value=10.0, key="gen_balance")