Traceback (most recent call last):
File “C:\Users\adela\PycharmProjects\Dashboard1\genFiles.py”, line 89, in callback_a
eFile = value + ex
TypeError: unsupported operand type(s) for +: ‘NoneType’ and ‘str’
Above I’m creating one string (eFile) from two others (value and ex). How to stop it from doing this?
this error is not related specifically to the callback. I assume your variable “value” is None based on the error you get.
Without your code it’s impossible to tell.
@AIMPED is right.
So unless at a point due to the data, value can be none, then you can add an if statement to check when it is none to do something else or skip.
if value == None: eFile = ex
If value cannot be None, then you may consider why it is so