st.checkbox
st.color_picker
st.date_input
st.multiselect
st.number_input
st.radio
st.select_slider
st.selectbox
st.slider
st.text_area
st.text_input
st.time_input
st.file_uploader
Widgets which support the on_click event:
st.button
st.download_button
st.form_submit_button
To add a callback, define a callback function above the widget declaration and pass it to the widget via the on_change (or on_click ) parameter.
Forms and Callbacks
Widgets inside a form can have their values be accessed and set via the Session State API. st.form_submit_button can have a callback associated with it. The callback gets executed upon clicking on the submit button. For example:
```python
def form_callback():
    st.write(st.session_state.my_slider)
    st.write(st.session_state.my_checkbox)
with st.form(key='my_form'):
