Slightly different from yours, but it shows a way to make a variable number of entry boxes. 

#!/usr/bin/perl

# http://perlmonks.org/?node_id=1166095

use strict;
use warnings;
use Tk;

my $numcel = 1;

my $mw = new MainWindow -title => 'Celcius to Farienhiet Converter';
$mw->geometry( '500x500' );

my $scl = $mw->Scale(
  -label=>"No of Celcius Values to Enter:",
  -orient => 'h', -digit => 2,
  -from => 1, -to => 10, -tickinterval => 1,
  -variable => \$numcel,
  )->pack( -fill => 'x' );

$mw->Button(
  -text=>"Push Me", -command =>\&push_button_sec,
  )->pack();

my $frame = $mw->Frame->pack( -fill => 'x' );

MainLoop;

sub push_button_sec
  {
  $_->destroy for $frame->children;
  for my $i (1..$numcel)
    {
    my $answer = '';
    my $input = '';
    my $item = $frame->Frame()->pack(-fill => 'x');
    $item->Label(
      -text => "Enter Celsius Value:",
      )->pack(-side => 'left');
    my $output = $item->Entry(
      -textvariable => \$input,
      )->pack(-side => 'left');
    $item->Label(
      -textvariable => \$answer,
      )->pack(-side => 'left');
    $output->bind( '<Return>' => sub {
      $answer = sprintf '%.1f', $input * 9 / 5 + 32;
      });
    }
  }

[download]

In reply to Re: set multiple entry boxes and text output boxes in perl TK at run time by Anonymous Monk
in thread set multiple entry boxes and text output boxes in perl TK at run time by Ganesh Bharadwaj1

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