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Author Checkbutton
MK

2008-02-29, 7:09 pm

What is wrong with this:

$exCB = $MW -> Checkbutton(-text=>"exclusion",
-variable=>$eX,
-command=>sub{print "\n$eX\n";},
-onvalue=>"on",-offvalue=>"off");

However, the value of $eX does not change regardless of the button's
state (ie. command just prints "on" when you check the box, and "on" when
you uncheck it).

Paul Gaborit

2008-02-29, 7:09 pm


À (at) Fri, 29 Feb 2008 10:08:45 -0600,
MK <halfcountplus@intergate.com> écrivait (wrote):
> What is wrong with this:
>
> $exCB = $MW -> Checkbutton(-text=>"exclusion",
> -variable=>$eX,
> -command=>sub{print "\n$eX\n";},
> -onvalue=>"on",-offvalue=>"off");
>
> However, the value of $eX does not change regardless of the button's
> state (ie. command just prints "on" when you check the box, and "on" when
> you uncheck it).


Try this "variant" :

$exCB = $MW->Checkbutton(-text => "exclusion",
-variable => \$eX,
-command => sub{print "\n$eX\n"},
-onvalue => "on",
-offvalue => "off");

and read the documentation (perldoc Tk::Checkbutton) :

[...]
Switch: -variable
Specifies *reference* to a variable...
[...]

--
Paul Gaborit - <http://perso.enstimac.fr/~gaborit/>
Perl en français - <http://perl.enstimac.fr/>
Marc Dashevsky

2008-02-29, 7:09 pm

In article < o9WdnQaoVraQs1XanZ2dnUVZ_j2dnZ2d@pghconn
ect.com>, halfcountplus@intergate.com
says...
> What is wrong with this:
>
> $exCB = $MW -> Checkbutton(-text=>"exclusion",
> -variable=>$eX,
> -command=>sub{print "\n$eX\n";},
> -onvalue=>"on",-offvalue=>"off");
>
> However, the value of $eX does not change regardless of the button's
> state (ie. command just prints "on" when you check the box, and "on" when
> you uncheck it).


Unless $eX is a reference to a scalar, you want:

-variable => \$eX,


--
Go to http://MarcDashevsky.com to send me e-mail.
MK

2008-02-29, 7:09 pm

On Fri, 29 Feb 2008 11:26:41 -0500, Marc Dashevsky wrote:


> Unless $eX is a reference to a scalar, you want:
>
> -variable => \$eX,


Correct you both are, i will watch for this word "reference" in the
future :)
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