#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = MainWindow->new;
$mw->title("Hi");

my $title = $mw->Entry( -text       => '',
                        -width      => 20,
                        -font       => 'Courier 12 bold',
                        -background => 'Orange',
)->pack( -ipadx => 35 );

$title->focus();

$mw->Button( -text       => 'Ok',
             -font       => 'Courier 12 bold',
             -background => 'Orange',
             -command    => sub{ Hello($title) },
  )->pack(   -side       => 'left',
             -ipadx      => 40
);

$mw->Button( -text       => 'Exit',
             -font       => 'Courier 12 bold',
             -background => 'Orange',
             -command    => sub { exit }
  )->pack(   -side       => 'right',
             -ipadx      => 40
);

# center your widget
center_widget($mw);

MainLoop;

sub Hello {
    my $title_val = $title->get;
    print "Hello - $title_val\n";
}




#================================================
# But : Center your widget
#================================================
sub center_widget {
  my ( $widget ) = @_;

  # Height and width of the screen
  my $width_screen  = $widget->screenwidth();
  my $height_screen = $widget->screenheight();

  # update le widget pour recuperer les vraies dimensions
  $widget->update;
  my $width_widget = $widget->width;
  my $height_widget = $widget->height;
  
  # On centre le widget en fonction de la taille de l'ecran
  my $new_width  = int( ( $width_screen - $width_widget ) / 2 );
  my $new_height  = int( ( $height_screen - $height_widget ) / 2 );
  $widget->geometry($width_widget . 'x' . $height_widget . "+$new_widt
+h+$new_height");
  
  $widget->update;
  
  return;
}
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