NULL is not read properly

Hi everybody,
It’s a while that I’m experiencing a strange problem with my code.

I’m using a real-time DB and I have to check if a specific node of the DB contains data or not, therefore I use the condition IF value != null as in the picture.

Sometimes, while live testing when it comes to this part of the code this function gives problems and shows the blank screen.

If I substitute this condition with another one the problem disappears and everything works again but, this would mean completely change the structure of the DB and so of my app.

I would like to ask if you are aware of this problem and if you know why sometimes this kind of solution works perfectly and some don’t.

Thank you so much!

The appearance of a white screen may indicate a memory access error. Simply put, you are trying to work with a nonexistent object.

Check your condition. the null check condition may not work and an attempt is being made to work with a nonexistent object. You may have null as a string type “null”.

Use step-by-step debugging with gradual addition of blocks to find out the block where the error occurs.

Display the values of all variables for monitoring.

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I’ve already debugged it thoroughly,
what i’m trying to signal is that the app works some days and other days it doesn’t and that I’ve identified the cause.

I’m sure that the null condition generates the problem and this happens randomly on certain days. ( when something like that happens i check all my backups to see if the problem persist)

what about to try the block "does value contain ‘null’ "??. (read the value as a string anche check if it contains “null”)

Yes, there are often situations in Thunkable X when it worked yesterday and it doesn’t work today. There are many reasons for this. But you are asking if the developers are aware that something is not working? How do I find out? Personally, I can only find out if I am given a link to the app and access to the database.

You say that you have already debugged everything, but I don’t see any error handling in your blocks. If your application gives a white screen, it means that either your blocks do not provide the necessary reliability to work, or it is a bug of the Thunkable x platform.

I get your point,
i just wanted to point it out to help the improvement of the platform.

Thank you