Hello fellow Monks,

I've been working with Tk for a few days now and I've run into something I can't get my brain around. How can I return or pass a value from a button event?

I'm writing an application that will let me compare photographs from a directory two at a time until I've decided on a favorite. The problem comes with trying to achieve this using Tk Buttons.

I've tried several different methods, but I still cant figure how to pass an array or return it through a button event subroutine, so that my array will eventually shrink as I make choices.

Any suggestions? 

#!/usr/bin/perl -w

use Tk;

chdir('images');
my @image_files = <*.gif>;

#initialize Main Window
my $mw = MainWindow->new;

#eventually I want to have this part continue until only one image rem
+ains
while (scalar @image_files > 1){                
    my $pic1    = shift @image_files;
    my $pic2    = shift @image_files;
    @image_files = show_two_buttons($mw, $pic1,$pic2,\@image_files);
}

#do something when we have one picture left.
#dosomething();
MainLoop;



sub show_two_buttons{
    my $mw = shift @_;
        for ($mw->packSlaves()){
            $_->destroy() if Tk::Exists($_); #clear out window
        }
    my $first_pic = shift @_;
    my $second_pic = shift @_;
    my @image_files = @{shift @_};
    #generate two buttons
    for $file($first_pic,$second_pic){
        my $image = $mw->Photo(-file=>$file);
        #cant figure how to return or pass arrays on the command here
        $mw->Button(    -image=>$image, -text=> $file, 
        -command=>[\&return_array, $file, \@image_files] 
                )->pack(-side=>"left");
    }
    return @image_files;#array never changes
}

sub return_array{
    my $file = shift @_;
    my @image_files = @{shift @_};
    push  @image_files, $file;
    print @image_files; #only contains one file
    return @image_files;#doesn't return to anything
}

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In reply to returning values from Perl-Tk events by thunders

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