在 OOP Python ZE5BA8B4C539C287BAAAEZ34

Question

I'm trying to figure out how to make a function that will be compatible with two classes. I have two classes with exact same parameters as the other, plus some more on each. And I need to use a function that is totally identical in both classes. Is there a way to use the function while only defying it once?

To make it more clear, here is my case. I have a Tkinter app with the form . The form is class by itself, but I also have a class that displays that from but filled and disabled by default as the display of details about a registered person . After clicking a button, you can change data in that form and update it in the database. Because the two classes are so similar, I used naming and everything from the form class to build the person detail class. But here is where I want to call the validation function. The same function would be called when submitting and also updating data. In each class, it would take only the self parameter, but I don't know how to define it only once and use it inside both Classes

Answer 1

in python as in many other programing languages you can create child classes which can inherit some attributes(parameters) and methods(functions) for parent class. Best practice in Object Oriented Programing for situations where some classes share same elements is to create one parent class which is inherited by both your child classes and by doing that you can pass them different parameters but write code only once.

class parent:
    def __init__(self, first, second):
        self.first = first
        self.second = second

    def shared_method(self, *some_parameters):
        # This method is doing something useful
        pass


# by putting some class name in brackets you are inheriting all from that class
class child1(parent):

    def __init__(self, first, second, third):
        # keyword super lets you avoid referring to the base class explicitly and takes for you everything that is already in parent's __init__
        super().__init__(first, second)
        self.third = third  # and you can than define new attributes specific to that class


class child2(parent):

    def __init__(self, first, second):
        super().__init__(first, second)

    def new(self, x):
        pass

Some advanced things you can research next are: how to create abstract classes so you can create objects only from child classes and not from parent and how to overwrite methods from parent class.

Object Oriented Programing (OOP) is large field in programming, but I hope I helped you at least get started and know what to look for next.