How do you Display User Data Across Screens in MIT App Inventor?

Hello everyone, I'm working on an app where users log in and sign up. I've built several screens, but I'm struggling with displaying the user's username on a different screen. After logging in, users land on the main screen. Then, they can navigate to the profile screen by clicking a button. However, I'm having trouble displaying the username where I want it.

I'm wondering if there are specific blocks I need to use to ensure the user stays logged in across screens. Can you guide me on how to implement this?

I'm using firebase as my DB.

To share data between different screens (real screens) you can use TinyDB or pass data directly from one screen to other.

Was it impossible to do in firebase? Or is there a way to connect firebase to tinydb?

But, do you want to validate the user each time there is a screen change? (has it sense?) or do you want only to share the username between screens?

When validating, will it check the database each time the screen changes to see which user was logged in? If so, this would be better, but I still need to display the username on a specific screen. And also when sharing username between screen was also need to validate if user was still logged in right?My apologies if it's confusing.

Once the user has been validated, why do you need to validate again when there is a screen change? If you need it again, then you need to request again to firebase (why?). Once you validate the user, then the user can "enter" to the app (move on to other screens). If rejected then the user will not be moved on to other screen.

If you want to share data between screens you can do it with "open another screen with value" block, to pass the data from one screen to other, or use a tinyDB to store data in one screen and have it available on the rest of the screens.

Now I see the problem. I only use the open screen, so it's not passing the value to another screen. Thanks man