Attempted to create second instance of HiddenComponentsCheckbox singleton

[fariba_ojaghi]

What is this error for and how is it fixed?

Attempted to create second instance of HiddenComponentsCheckbox singleton

[Taifun]

I searched the community for you

https://community.appinventor.mit.edu/search?context=topic&context_id=144529&q=HiddenComponentsCheckbox%20singleton&skip_context=true

There was this statement from @Susan_Lane

Problem with HiddenComponentsCheckbox - Hidden Elements not showing

This error shouldn't have any effect. A singleton is a class that should only ever have one instance. The code should never try to create a second one, and clearly in this situation it is. However, this check is to prevent a second copy of the checkbox from ever being created. After this error is logged, the code returns the existing checkbox instead of creating a new copy. I need to figure out what circumstances are causing App Inventor to try to create a second copy of the hidden components…

Taifun

[Susan_Lane]

I never did find what was causing this, but I'm testing out a different implementation of the checkbox that shouldn't have this issue.