"It seems that by default tk passes a ref to the object you bound to. Once I realized that that ref was also in @_ I was able to use that and trim my parameter list by one..also making it in the correct order"

I'm not sure what question you are asking, other than the parameter order, but it got me thinking about your statement that tk passes a ref to the callback. At first it didn't strike me as odd, because in perl gtk, all callbacks get $self passed to it as it's first parameter. But then I tried it, and it dosn't in Tk. In Tk a hash exists with the data in it, but it isn't passed by default. The following code demonstartes what I'm talking about. It creates a bunch of "anonymous buttons" and it dosn't pass a ref to the pressed button to the callback sub-routine. The information is available from the hash returned by Tk::widget. Maybe your problem is you think the ref is being passed as an array, but it's actually in an unordered hash. Use the Dumper line to see all that is contained in $caller. Anyways....I learned something today.

#!/usr/bin/perl use strict; use Tk; use Data::Dumper; my $mw = MainWindow->new; for(0..4){ $mw->Button(-text => "Hello World$_", -command=>[\&change])->pack; } MainLoop; sub change { #Tk dosn't pass it's widget reference in callbacks #Only the bind() method will implicity pass a widget reference, and ev +en #this default (and generally preferred) action can be defeated. #use the widget my $caller = $Tk::widget; #print Dumper([$caller]); print "$caller "; print $caller->{'_TkValue_'},' '; my $text = $caller->cget('-text'); print "$text\n"; $caller->configure(-text=>"Hello Stranger"); }

In reply to Re: Tk event-binding parameters by zentara
in thread Tk event-binding parameters by Grygonos

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