Redrawable types should be documented

[monchier]

Related to this: https://discuss.streamlit.io/t/force-redraw-of-an-earlier-element/635

Please add documentation of which types in DeltaGenerator are redrawable.

[snehankekre]

Closing this issue as it has not come up since 2019. Obviously, if people start mentioning this again, we can add a note to the docs.

[ivanmkc]

I have an issue where I update a variable that changes which container is drawn:

        if self.view_model.mode == "A":
            with st.container():
                st.header("A")
                next_button_tapped = st.button("Go to b")

                if next_button_tapped:
                    self.view_model.mode = "B"

        elif self.view_model.mode == "B":
            with st.container():
                st.header("B")
                next_button_tapped = st.button("Go to A")

                if next_button_tapped:
                    self.view_model.mode = "A"

The problem is that the mode attribute is updated after the "redraw", so I have to it only works if I tap the button "twice". Once to set it, and once to redraw. Even then, the UI and state are out of sync.