use warnings;
use strict;
use Tk;

my $font = "{Times New Roman} 32";
my @chosen;
my $grid_width = 10;

my $mw = MainWindow->new( -title => 'Keno', );

my $header_frame = $mw->Frame(
    -relief => 'raised',
    -border => 3
  )->grid(
    -row        => 0,
    -column     => 0,
    -columnspan => $grid_width,
    -sticky     => 'ew'
  );

$header_frame->Label(
    -text => 'Welcome to Keno',
    -font => "{Comic Sans MS} 24 bold",
)->pack;

my ( $row, $column );

for ( 0 .. 79 ) {
    $column = $_ % $grid_width;
    $row++ unless $column;
    $mw->Button(
        -width   => 2,
        -font    => $font,
        -text    => $_ + 1,
        -command => [ sub { Button_Click( $_[0] ) }, $_ + 1 ]
      )->grid(
        -row    => $row,
        -column => $column,
      );
}

MainLoop;

sub Button_Click {
    my $arg = shift;
    if ( defined $chosen[9] ) {
        print 'You already chose 10 numbers: ';
        print join ', ', @chosen;
        print "\n";
    }
    else {
        print "$arg was choosen\n";
        push( @chosen, $arg );
    }
}