#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11140544
use warnings;
use Tk;
use Tk::TableMatrix;

my ($nrows, $ncolumns) = (1000, 20);

my $mw = MainWindow->new();
$mw->configure(-title=> "TableMatrix Demo");
$mw->geometry("1000x400+0+0"); 

my $buttonbar = $mw->Frame(-bg => 'blue',
  )->pack(-fill => 'x');
$buttonbar->Button(-text => 'Exit', -command => sub{$mw->destroy},
  )->pack(-side => 'right', -fill => 'x', -expand => 1);
$buttonbar->Button(-text => 'Set Size', -command => sub{},
  )->pack(-side => 'right', -fill => 'x', -expand => 1);
$buttonbar->Button(-text => 'Remove Column',
  -command => sub{},
  )->pack(-side => 'right', -fill => 'x', -expand => 1);

my %MainHash;
my $tMain=\%MainHash; #main data structure for the TableMatrix

my $table_frame = $mw->Frame(-height=>'10',-width=>'30',
                       -relief=>'groove',-borderwidth=>'3'
                       )->pack(-expand=>1, -fill=>'both',-pady=>'0');
                       
my @col_heads = map{"Col Head $_"}0..$ncolumns;                       
                       

###
### Main TableMatrix object
###
my $table = $table_frame->Scrolled('TableMatrix',
  -cols => scalar(@col_heads),
  -rows =>1000,   #fixed number of rows!!! need to grow this dynamically!
                  #I forget how I did this, but it is possible
# -width => 5,  #minimum width in columns to be shown
# -height => 10, #minimum number of rows to be shown - seems to limit!! not Min!??
 -titlerows => 1,
 -variable => $tMain,
 -selectmode => 'single',
 -state => 'disabled',   # no direct editing of cells
 -resizeborders => 'col', 
 -bg => 'white',
 -rowheight => 1,  #make row display more compact....
 -bd => [0,1,0,1],
 -justify => 'left',
 -drawmode => 'compatible',
 -wrap => 0,
 -relief => 'solid',
 -scrollbars=>'se',
 -exportselection =>0,
)->pack(-expand =>1, -fill=>'both');
$table->rowHeight(0,2);  #varies height of title row (0)
$table->tagRow('title',0);
$table->tagConfigure('title', -bd=>2, -relief=>'raised');

foreach my $row (0..$nrows-1)
{
    foreach my $col (0..$ncolumns-1)
    {
        $tMain->{"$row,$col"} = "row $row col $col"; 
    }
}

set_col_width($table,@col_heads); #THIS WILL CAUSE A SCREEN REFRESH!

sub set_col_width{
   (my $table, my @col_head) = @_;
 
   my $i=0;
   foreach my $col (@col_head){ 
     $table->colWidth($i++, length($col));
   }
}

MainLoop;