Execution flow

Change execution

By default, Streamlit apps execute the script entirely, but we allow some functionality to handle control flow in your applications.

Modal dialog

Insert a modal dialog that can rerun independently from the rest of the script.

Python

@st.dialog("Sign up")
def email_form():
    name = st.text_input("Name")
    email = st.text_input("Email", type="email")

Fragments

Define a fragment to rerun independently from the rest of the script.

Python

@st.fragment(run_every="10s")
def fragment():
    df = get_data()
    st.line_chart(df)

Rerun script

Rerun the script immediately.

Python

st.rerun()

Stop execution

Stops execution immediately.

Python

st.stop()

Group multiple widgets

By default, Streamlit reruns your script everytime a user interacts with your app. However, sometimes it's a better user experience to wait until a group of related widgets is filled before actually rerunning the script. That's what st.form is for!

with st.form(key='my_form'):
    name = st.text_input("Name")
    email = st.text_input("Email", type="email")
    st.form_submit_button("Sign up")

with st.form(key='my_form'):
    name = st.text_input("Name")
    email = st.text_input("Email", type="email")
    st.form_submit_button("Sign up")