The widget is being created anew on each page so its value is being initialized to its default value. I’d create a separate ‘value cache’ to store values between pages. Something like this below. (Note, when a widget has a key and you initialize its value with a session state key value other than the widget’s own key value, Streamlit will complain. Therefore, I have removed the widget keys.)
import streamlit as st
# Instantiate the Session State Variables
if 'cache' not in st.session_state:
st.session_state.cache = {'name': '', 'age': '', 'gender': ''}
# Sidebar Widgets
sidebar_Title = st.sidebar.markdown('# Streamlit')
sidebar_pages = st.sidebar.radio('Menu', ['Page 1', 'Page 2', 'Page 3'])
# Page 1
def page1():
st.session_state.cache['name'] = st.text_input('What is your name?', value=st.session_state.cache['name'])
# Page 2
def page2():
st.session_state.cache['age'] = st.text_input('What is your age?', value=st.session_state.cache['age'])
# Page 3
def page3():
st.session_state.cache['gender'] = st.text_input('What is your gender?', value=st.session_state.cache['gender'])
# Navigate through pages
if sidebar_pages == 'Page 1':
page1()
elif sidebar_pages == 'Page 2':
page2()
else:
page3()
st.write(st.session_state.cache)
@ismet_aksoy here is your solution. You need 2 separate variables and a callback function.
import streamlit as st
# Instantiate the Session State Variables
vars = ['name', 'age', 'gender']
for _ in vars:
if _ not in st.session_state:
st.session_state[_] = ''
# Sidebar Widgets
st.sidebar.markdown('# Streamlit')
sidebar_pages = st.sidebar.radio('Menu', ['Page 1', 'Page 2', 'Page 3'])
def callback_function(state, key):
# 1. Access the widget's setting via st.session_state[key]
# 2. Set the session state you intended to set in the widget
st.session_state[state] = st.session_state[key]
# Page 1
def page1():
name = st.text_input('What is your name?', key='name_key', on_change=callback_function, args=('name','name_key'))
# Page 2
def page2():
age = st.text_input('What is your age?', key='age_key', on_change=callback_function, args=('age','age_key'))
# Page 3
def page3():
gender = st.text_input('What is your gender?', key='gender_key', on_change=callback_function, args=('gender','gender_key'))
# Navigate through pages
if sidebar_pages == 'Page 1':
page1()
elif sidebar_pages == 'Page 2':
page2()
else:
page3()
st.write(st.session_state)
The key and the session state you want to set cannot be the same. Otherwise, when the new page comes up, the widget is re-drawn, and the widgets key resets the session state.
Here, I added a callback function, which can be used generally for setting most session states from the widgets using on_change and args parameters. Note: if you are going to set a default value on certain widgets, you may need to complicate things with a third varable.
No not getting it working well, but thanks for the interest.
My code example above does remember the slider setting across pages. However, the slider
jumps in valued and if you drag it left then try to Goth other way it stops and you have to let go and grab it again. I’m sure this is because its a sort of circular ref. - you move the slider, it updates the state and then the state sets the slider etc.
here is my quick hack in context:
import streamlit as st
# Instantiate the Session State Variables
vars = ['name', 'age', 'gender', 'level']
for _ in vars:
if _ not in st.session_state:
st.session_state[_] = ''
st.session_state.level=1
# Sidebar Widgets
st.sidebar.markdown('# Streamlit')
sidebar_pages = st.sidebar.radio('Menu', ['Page 1', 'Page 2', 'Page 3'])
def callback_function(state, key):
# 1. Access the widget's setting via st.session_state[key]
# 2. Set the session state you intended to set in the widget
st.session_state[state] = st.session_state[key]
# Page 1
def page1():
name = st.text_input('What is your name?', key='name_key', on_change=callback_function, args=('name','name_key'))
st.write(st.session_state.name)
# Page 2
def page2():
age = st.text_input('What is your age?', key='age_key', on_change=callback_function, args=('age','age_key'))
st.slider('level_1', min_value=0, max_value=10, value = st.session_state.level, key = 'level_key',on_change=callback_function, args=('level','level_key'))
st.write(" ")
st.write('level_1 = ',st.session_state.level_key)
# Page 3
def page3():
gender = st.text_input('What is your gender?', key='gender_key', on_change=callback_function, args=('gender','gender_key'))
# Navigate through pages
if sidebar_pages == 'Page 1':
page1()
elif sidebar_pages == 'Page 2':
page2()
else:
page3()
st.write(st.session_state)