[Tutor] Multiple buttons, One callback (fwd)

[Michael Lange]

> ---------- Forwarded message ----------
> Date: Fri, 4 Aug 2006 09:32:48 -0700 (PDT)
> From: Michael Cochez <michaelcochez at yahoo.com>
> To: dyoo at hkn.eecs.berkeley.edu
> Subject: Multiple buttons, One callback
> 
> Hi Danny,
> I've just been reading your reply on this subject at
> http://mail.python.org/pipermail/tutor/2005-September/041358.html
> about a year ago.
> I need something like this but also something more:
> I'm making an app with an interface that is going to
> look like in the added image. The "=" buttons are
> there to copy the contents of the previous lines to
> the current line.
> To make the buttons tried a lot of things but the
> problem is: the number of buttons is always different
> (one less as the number of day) so it can be none or
> 20 or something else. So i putted the creation in a
> for loop.
> But now the real problem: every button must have its
> own callback(because the linenumber is different) So
> my question is: how can I give each button its 'own'
> callback while only having one (the callbacks are all
> the same but with another value of linenumber. I added
> a piece of the code to show what i mean.

I would use a lambda for this, like:


def makeidentical(linenumber):

    print "the linenumber is: %d" % (linenumber)


for day in datelist:

    a=datelist.index(day)

    if a>0:#on every line exept the first

        identicalbutton=Button(frame2,text="=",command=lambda : makeidentical(a))

        identicalbutton.grid(row=a+2,column=3,sticky=W)

        frame2widgets.append(identicalbutton)


I hope this helps

Michael