Streamlit v1.49.0, Python 3.13.5
I have an st.form. Inside of that form is an st.multiselect. I want to add an st.checkbox that appears after the multiselect that, when checked, selects ALL the values in the multiselect.
I am aware that, under normal circumstances, changes inside a form don’t take effect until after the form is submitted. I have reviewed a number of threads (here, here, and here especially), and the answers either:
a) aren’t exactly what I’m looking for - e.g. they update a multiselect based on a checkbox, but not inside a form
b) don’t seem to work anymore, at least not on my Streamlit version - eg this solution or this one
Is there a way to do this? It appears based on some of the above answers it may have been possible at one point, but doesn’t seem to work on Streamlit v1.49.0.