Quoting Michael Lange <[EMAIL PROTECTED]>:
> I don't think it will work this way, because you don't catch the event
> bind() passes to the callback
> (you also use a variable "e" in makeCallback() that isn't defined
> anywhere).
That's what the variable 'e' is doing!
Here is some code I just wrote and tested:
>>> def clicked(w):
... print 'Widget %s clicked! Text: %s' % (str(w), w.cget('text'))
...
>>> def makeCallback(w):
... def callback(e):
... clicked(w)
... return callback
...
>>> from Tkinter import *
>>> tk = Tk()
>>> for text in ['foo', 'bar', 'baz']:
... lb = Label(tk, text=text)
... lb.pack()
... lb.bind('<Button-1>', makeCallback(lb))
...
'11427352callback'
'12096856callback'
'12097016callback'
>>> # Now to click on the labels.
Widget .11444992 clicked! Text: foo
Widget .12097096 clicked! Text: bar
Widget .12097336 clicked! Text: baz
Widget .12097096 clicked! Text: bar
Widget .11444992 clicked! Text: foo
-----------------
Lambdas are (probably) going away in Py3000, so I am trying to get away from
using them (it's hard, though :-) ). Anyway, makeCallback() defines a function
which takes one argument (that's the event), and then calls clicked() on the
widget argument to makeCallback(). That function is returned and bound to
<Button-1>.
Here's a simpler example of the same thing:
>>> def add(x):
... def addx(y):
... return x + y
... return addx
...
>>> f = add(5)
>>> f(3), f(5), f(9)
(8, 10, 14)
(of course, I could have done the same thing by writing: f = (5).__add__ ...)
--
John.
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