I want to create a new cell file in xcode, and "A" appears next to the result, and then there will be no error during the writing process, but the cell will not be displayed:

I would like to ask what does the "A" mean? Why is my cell not showing up?
I want to create a new cell file in xcode, and "A" appears next to the result, and then there will be no error during the writing process, but the cell will not be displayed:

I would like to ask what does the "A" mean? Why is my cell not showing up?
It means the file is unknown to git and that you should git add it.
Whatever problem you are having with your code has nothing to do with that A. You should ask another question where you provide some of your code if you need help.
If you don’t know what git is and you aren’t using it — then you can ignore this for now.