Alex Hall wrote:
Hi all,
I am a bit confused about classes. What do you pass a class, since all
the actual information is passed to __init__? For example, say you
have a dog class. The dog object has a name, a size, and a color. I
believe you would say this:
class dog():
def __init__(self, name, size, color):
self.name=name
self.size=size
self.color=color
Here you have defined a dog class (you have not called it, yet).
What, then, gets passed to the class constructor?
class dog(whatGoesHere?):
whatGoesHere = any parent classes (the constructor is *not* being called
yet)
parent classes can be used when you want what they have, but need to
either add more, or change some, of the methods/attributes that the
parent has.
Sometimes I see things passed to this. For example, if you create a
class for a wxPython frame, you will say:
class myapp(wx.App):
wx.App is not being passed, per se, rather Python is being told that
myapp is based on wx.App, and will have all the methods/attributes that
wx.App has, plus whatever else follows.
So far, all that has been done is to _define_ classes.
class contact():
def __init__(self, name, email, status, service):
self.name=name
self.email=email
self.status=status
self.service=service
Here, I do not pass anything to the class, only to __init__. What is going on?
You have defined a class -- nothing more, nothing less.
When you actually call the class is when any necessary items are passed
to the constructor (__init__):
a_dog = dog('Ralph', 'big', RED)
this_app = myapp()
fred = contact('Fred Flinstone','f...@flinstone.gv','active','exemplary')
Hope this helps.
~Ethan~
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