General advice on page render optimisation?

[mathcatsand]

@altanner

Can input widgets be altered, and Streamlit do nothing until a “submit” button is pressed?

You can put your widgets in a form if you would like to allow a user to make multiple changes before committing to rerunning your script.

st.form - Streamlit Docs

@altanner

Or, if jumping through render is unavoidable, is there a way of fading out the screen, show spinner, and re-render or otherwise making it look more professional?

You can use st.empty to clear a screen. I just wrote a snippet in another post here:

Page refresh is slow and ugly

I vote for the kitty! Have you tried using st.empty? By your description, I am assuming you have a single script providing your pages instead of using the built-in multipage functionality. The ghosting of widgets is something Streamlit does while waiting to see if it those widgets are going to be kept or discarded. If you have each page in a container within an empty element, you could have a means to tell Streamlit to just throw everything away and not wait. import streamlit as …