[PyKDE] A simple PyQt program

Gordon Tyler gordon at doxxx.net
Sun Jun 27 06:15:00 BST 2004

Joshua wrote:
> TypeError: update() takes exactly 2 arguments (3 given)
> I don't understand this, since I only gave update 2 arguments. If anyone 
> could shed some light on this, I'd greatly appreciate it. Here's the code:

This is something fairly fundamental to Python programming, so you have 
to make sure that you understand how this works.

When you have a class with a method:

class Foo:
     def bar(self, x):
         print x

And you call that method on an instance of the class:

f = Foo()

The instance, f, is automatically passed as the first argument to the 
function before any other arguments that are provided in the call. 
Therefore, when you declare methods in a class they must have a "self" 
parameter as the first parameter.

There's more to this than I've explained here so you should read a 
Python book or online manual.


More information about the PyQt mailing list