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Brandon Wall
5,512 PointsAssign this to self so we can get back to it later?
When we build the function build_buttons, there is a moment in the video at 2:0something, cant see because this window is in the way, but its in the first 10 seconds of the 2 minute mark where Kenneth Love defines self.start_button and i believe he is saying "And we're going to assign this to self so we can get back to it later"
What exactly does that mean? I'm still having trouble understanding the whole self argument on methods. I've read a lot about them, scoured the web for info, i know it's referring to the instance of the class that the method is called on...but i still don't really understand.
What would happen if we defined start_button without the self argument?
1 Answer
Kenneth Love
Treehouse Guest Teacherself points back to the current instance. So it's the instance of our app that's running and that all of the methods in our app's class know about. Since we want to be able to get back to those buttons from other methods, without having to provide them to those methods, we stick them onto the instance so they'll be available.
If we didn't assign them to self, and we just made it as start_button, it wouldn't exist anywhere outside of that method and we wouldn't be able to get to it again later.
Brandon Wall
5,512 PointsBrandon Wall
5,512 PointsSo self is sort of expanding the scope of our variable within the method so it is able to be referenced anywhere in the instance of a class? If we didn't give it an explicit self, then the scope of that widget would only be accessible from within that method, and we would have to define it again and again on different methods? Am I on the right track? I think i got it :D
Kenneth Love
Treehouse Guest TeacherKenneth Love
Treehouse Guest TeacherIt's not really changing the scope of the variable, but, yeah, that's the general idea.