how can I change the attribute value in supercalass from subclass permanently in python-CodePudding

I want to change the value of attribute pen_color in View class permanently when I call changeColor method and the value still permenant unless I call the method again with another color, when I call changeColor method the pen_color attribute still have the same value and I don't want such thing Is there any way to do such thing or not ?

class View: 
    def __init__(self):
        self.pen_color = 'red'
    

class Button(View): 
    def __init__(self):
        pass
        
    def changeColor(self):
        super().__init__()
        
        self.pen_color = 'green'

CodePudding user response：

You should move the declaration of pen color into a class attribute rather than an instance attribute and reference it as View.pen_color.

Having done that View.pen_color will be permanent and global, but can be shadowed by self.pen_color in either View or Button instances.

CodePudding user response：

This is not best practice, but if you really want then you can do it. To do this is to make a function to set the initial color in the superclass' __init__(), then change that function later on. Here's an example:

class View:
    def __init__(self):
        self.initColor()

    def initColor(self):
        self.pen_color = 'red'


class Button(View):
    def __init__(self):
        super().__init__()

    def changeColor(self, color):
        def newColor(self):
            self.pen_color = color
        View.initColor = newColor


btn = Button()
print(btn.pen_color) # returns 'red'
btn.changeColor('green')

btn2 = Button()
print(btn2.pen_color) # returns 'green'