Fellow monks,

I'm working on a Tk app that uses the ListBox method in Tk to return results from a search. All well and good until it goes out of scope in the subroutine that sets it up.

What I am trying to do, without success up to this point, is to create a reference to this method so that I don't have a huge subroutine that both defines the list box and takes care of it's processing.

I've tried to set up my list box with a reference as: 

# snippet of a subroutine that defines the widget layout
my $res;

{
my $results = $search_frame->Listbox( -background => "white",
                                      -relief => "sunken",
                                      -borderwidth => 2,
                                      -width => 20,
                                      -height => 12,
                                      )
                                      ->place( -in => $search_frame,
                                               -x => 20,
                                               -y => 175);
$res = \$results;
}

[download]

but I keep getting the message that $ref isn't defined when I try to access it later in the program by 

$res->insert('end', $list[$_]->{last});

[download]

I'm assuming, and perhaps incorrectly, that when I move out of the sub that defines the listbox, I'm losing scope. But if I have to move the $ref outside as a global, doesn't that sort of defeat the purpose of defining it as a reference to the ListBox method?

I've been banging my head for a few days on this now, so any help would be greatly appreciated!

There is no emoticon for what I'm feeling now.

In reply to Calling a TK Method by reference by Popcorn Dave

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