I don't really have a good grasp as to how to efficiently force the program to check every x seconds?
......
It turns out that $mw->after(1000, \&sub); works.. then just add that into the sub to repeat..

Hi, Tk::after is usually used for a one-shot delay. What you want is Tk::repeat. Try 


my $repeater = $mw->repeat(1000, \&sub); 
.... 
$repeater->cancel;  # when you want to stop it

[download]
and you will not need to repeatedly call Tk::after in your sub.

Here is a basic example: 

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

my $mw = MainWindow->new(title => "Timer");
my $elapsed_sec = 0;
my $elapsed_sec_label = $mw->Label(-textvariable => \$elapsed_sec)->pa
+ck();

my $repeater; # declare first so it can be accessed in the callback
    
$mw->Button(-text => "reset", 
     -command => sub {
               $elapsed_sec = 0;
               &repeater();
             })->pack();

$mw->Button(-text => "exit", 
     -command => sub { exit })->pack();

# start first run
&repeater();
               
MainLoop;


sub repeater{

#this is repeated every second, and you can put your is_playing here
$repeater = $mw->repeat(1000 => sub {

               $elapsed_sec ++;
               
               if ($elapsed_sec > 4){ $repeater->cancel }
               
               }  ); 
      
}

[download]
I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

In reply to Re: TK Timed action by zentara
in thread TK Timed action by randor

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.