how to change attribute of parent class

Question

I have two classes. In the object oriented methodology, I can change parent attribute from low level class. In python, how can I change variable of the parents from other class ? What I have

class Concurrent( threading.Thread):
    def __init__(self):
         self.rec = Rec()
         self.rec.start()
         self.parentvar = None # I have change this variable
         self.secondParentVar = [] # or use this

class Rec(Concurrent):
    def run(self):
        # from here, change variable of the parent Conccurent class variable

@SnakesandCoffee I have not put any variable name. If you want `parentVar = None ` — user2396467, May 20 '13 at 06:55
@user2396467 Does this code run? I can't seem to get the class definitions to work. — Snakes and Coffee, May 20 '13 at 07:02
@SnakesandCoffee why do I need to give all code ? It is working. — user2396467, May 20 '13 at 07:02
@user2396467 your current code doesn't work since `Rec()` calls `Rec.__init__` which is inherited from `Concurrent.__init__`, which conveniently calls `Rec()` — Snakes and Coffee, May 20 '13 at 07:06
@SnakesandCoffee Do not bother with whether code is running or not. Last time, I know how to create a class. — user2396467, May 20 '13 at 07:07
@user2396467 Generally the policy on SO is for the OP to include a http://sscce.org/ SSCCE. — Snakes and Coffee, May 20 '13 at 07:11
In Python you can change anything from anywhere. What have you tried? — Lennart Regebro, May 20 '13 at 07:21
@LennartRegebro After I have started the rec instance, I have tried to change the concurrent instance variable. I have put print statement in concurrent instance but print only shows first initialized value such as none. — user2396467, May 20 '13 at 07:24
Then you are doing something wrong, and we won't know what until you actually include examples of *what you have tried*. — Lennart Regebro, May 20 '13 at 07:25
@lennart-regebro but it should be mentioned that you don't necessarily always want to: http://stackoverflow.com/a/1641236/1514681 — LJNielsenDk, May 20 '13 at 07:26

score 2 · Answer 1 · answered May 20 '13 at 07:04

i think something like this would work:

class Concurrent( threading.Thread):
    def __init__(self):
        self.rec = Rec()
        self.rec.start()
        self.parentvar = None 

class Rec(Concurrent):
    def __init__(self):
        Parent.__init__(self)
        self.parentvar = #new variable
        self.secondParentVar = [list1, list2]

score 0 · Answer 2 · answered May 20 '13 at 07:21

0

What you probably want is this:

class Rec(Concurrent):
    def run(self):
        self.parentvar = "new value"

answered May 20 '13 at 07:21

Lennart Regebro

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how to change attribute of parent class

2 Answers2