Hello,

I'm trying to fill in a textvariable in a Tk grid, and it only seems to work if I assign the array elements to scalar variables first.

So it works when I use:
->Label( -textvariable => \$some_scalar )
but not when I do this:
->Label( -textvariable => \$some_array[1] )

In any perl documentation I've seen, they should both be treated as references to scalars, but the text never shows up in the second case. Here's my stripped down code that demonstrates the problem (at least on all the systems I've tried!). It should make a 2x2 grid with "abc" and "def" on the top row, and "1" and "2" on the bottom row. "abc" doesn't show up when I use the array element reference.

What am I overlooking?

Peter 

#!/usr/bin/perl

use Tk;
use strict;
use warnings;

my (@status_label, @status_value);
my ($entry11, $entry12, $entry21, $entry22);

#---
my $mainwindow = MainWindow->new();
$mainwindow -> title('testtk');

my $frame_top = $mainwindow
    ->Frame()
    ->pack(-side=>'top');
my $label1 = $frame_top
    ->Label( -textvariable => \$status_label[0] )
    ->grid(-row=>1,-column=>1);
my $label2 = $frame_top
    ->Label( -textvariable => \$entry12 )
    ->grid(-row=>1,-column=>2);
my $value1 = $frame_top
    ->Label( -textvariable => \$entry21 )
    ->grid(-row=>2,-column=>1);
my $value2 = $frame_top
    ->Label( -textvariable => \$entry22 )
    ->grid(-row=>2,-column=>2);

#---
@status_label = ("abc","def");
@status_value = (1,2);
&update_interface();
MainLoop;

#---
sub update_interface {
    $entry11 = $status_label[0];
    $entry12 = $status_label[1];
    $entry21 = $status_value[0];
    $entry22 = $status_value[1];
}

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In reply to why won't Tk textvariable take a reference to an array element? by peter.mao

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