#!/usr/local/bin/perl


use strict;
use Tk;

my $Mycount = 0;
my $submain = MainWindow->new();

my $buttons = $submain->Frame()->pack(-side => 'top');

my $status = $buttons->Button(-text => 'Click to Clear',
                   -command => sub {$submain->destroy;}
                    )->pack(-side=>'left');

my $text1 = $submain->Text ('-width'=>100, 'height'=>20);
$text1->pack(-side => 'left', -fill => 'y');


my $doit = $buttons->Button(-text => 'Do It',
                   -command => [ \&theLoop =>  $submain, \$Mycount],
                    )->pack(-side=>'left');

$text1->insert('end', "start\n");
$text1->pack;

MainLoop();

sub theLoop {
	my $widget = shift;
	my $Mycount = shift;
	my $line = '';
	
	$$Mycount++;
	#for(my $loop=0; $loop <= 3; $loop++ ) ## Looping handled by timer...
	#{  
		#sleep 1;  Incompatible with Tk MainLoop - It pauses the *entire* application
		print "$$Mycount\n";
	           
		if    ( $$Mycount == 1 ) { $line = "$$Mycount case 1\n"; }
		elsif ( $$Mycount == 2 ) { $line = "$$Mycount case 2\n"; }
		else         { $line = "$$Mycount something else\n"; }
	           
		$text1->insert('end', "$line");
		#$text1->pack;
	#}
	## Here is where we implement the delay.... and the loop
	## We simply check to see if our loop max has been reached, then if not, 
	## set a future event to call this subroutine again.
	## The 500 is the number of milliseconds to wait before calling.
	## This is better programming in Tk, since the sleep command stops everything
	## which is very bad with a GUI. (think M$ when a low level call happens)
	if ($$Mycount < 3)
	{
		my $delay = $submain->after(500, [\&theLoop => $widget, $Mycount]);
	}
}