It seems that we can’t set a default option on widgets without getting a warning like this on our dashboards: The widget with key “reporting” was created with a default value but also had its value set via the Session State API. What’s the rationale for this? It doesn’t seem right because the p…

Hey @quantoid , When the team was designing st.session_state they had played around with a few options on how state would interact with parameters like value for specifying default ones. For right now, this is expected behaviour but the team is looking into changing it, along with some other changes…

I’ve opened an issue for this warning case. Hope someone can make a way to not show this.

Hey @eduardochaves :wave: Here’s how you can workaround the issue. Use one session state variable to hold the default value (e.g. “custom_date”), and another to assign as the widget key (e.g. “date_key”). If the widget key doesn’t exist in session state, assign the default value to the former varia…

This does not work for me. I get the same behavior where the warning shows the first time the app is launched.

If you describe your situation there should be a way to tweak the code to avoid the error. Usually when I encounter this, I have a bit more interaction happening so the exact tweak varies by situation…

Without actually modifying the code in streamlit/elements/utils.py I am not sure how to modify the _shown_default_value_warning variable. So the proposed solution of modifying it locally in the app script should not work since the utils script is not accessing the variable from the app script. The o…

I’m suggesting not doing anything with utils.py at all and just changing the app code in a way to avoid the error. If you don’t trigger the warning, then it doesn’t matter if it’s set to show or not. :slight_smile: It’s just the my advice on how to not trigger the warning is dependent on the scenar…

The proper fix is not passing a default value and a key in the same call.

Yes, I understand that. However, the text_input does not behave in the way I need it to. I will create a new post to explain since it is a specific use-case. Thanks for the help. This community is quick to respond and that is awesome!

For me, the issue is that avoiding setting default and keys doesn’t seem possible. I have a loop containing w_param = st.number_input( label = f"Width {n}", label_visibility = "collapsed", value = float(0.1), key = f"w_input_{n}") .... and then later in a process + update widge…

Why do default values cause a session state warning?

Using Streamlit

CharlesDexterWard March 6, 2023, 6:04pm 23

Thanks for the suggestion Here is the full issue I’m having. I figured it’s best to create a new post since there are a few issues that using a key and value almost solved. Text_input behavior for updating a session state value is not intuitive for my use-case

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Why do default values cause a session state warning?

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