Anvil IDE Run page do not trace error

Anvil Q&A
2

Hi,

we need more information to help you, such as :

  • clarity - does this error show on a published app or when run in the IDE?
  • does any part of the app load (ie do any forms show) before the error?
  • if nothing shows, maybe paste the code in the startup form here
  • if you can provide a clone link to your app along with the above information, that would speed up diagnosis

Also, please read this : How to ask a good question which shows how to ask a good question to maximise the chances of receiving timely and helpful advice.

edit

This is from ChatGPT :

The error message “NameError: name ‘self’ is not defined” typically appears in Python when you try to use the keyword `self` outside the context of an instance method in a class. The `self` keyword is used to refer to the instance of the class and is automatically passed as the first argument to instance methods.

Here are a few scenarios that might lead to this error:

  1. Using self outside any method: If you use self in the class body but outside any method, you’ll get this error.

python

class MyClass:
self.my_variable = 5 # This will raise an error


* **Using `self` in a static or class method**: `self` is not automatically passed to static methods or class methods. If you try to use it, you'll get the mentioned error.

python

* ```
class MyClass:
    @staticmethod
    def my_static_method():
        print(self.my_variable)  # This will raise an error
    
    @classmethod
    def my_class_method(cls):
        print(self.my_variable)  # This will also raise an error
  • Forgetting the self parameter in a method definition: When defining instance methods, the first parameter should be self, which refers to the instance itself. If you forget to include self and then try to use it in the method, you’ll get an error.

python

class MyClass:
def my_method():
print(self.my_variable) # This will raise an error


* **Using `self` outside of a class**: If you try to use `self` in a regular function or in the global scope (i.e., outside of any class), you'll get the same error.

python

1. ```
def my_function():
    print(self.my_variable)  # This will raise an error

To fix this error, ensure that you are using self correctly within the context of instance methods in a class and that you have included it as the first parameter in the method definition. If you are working with static or class methods, avoid using self and use the appropriate parameters instead (cls for class methods).

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