Tk already has "threads" :-S try this: 
use Tk;

my $mw = new MainWindow();
my $button = $mw->Button(-text => "HEY")->pack();
$mw->after(1,\&thread_sub); # after 1 ms, calls thread_sub
# it'll run like a thread, but isn't really!  
# See http://www.foo.be/docs/tpj/issues/vol1_3/tpj0103-0006.html

MainLoop();

sub thread_sub
{
   for (my $i=0; $i<10_000_000; $i++)
   {
      # DO NOTHING. LET THE TIME BE TIME
   }

   # CHANGE BUTTON'S TEXT PROPERTY TO "hey" HERE
   $button->configure(-foreground=>'red');
}

[download]
It's a weird example though... what were you planning on doing? Do you really need threads or would Tk timeslicing do?

In reply to Re: How to change a Tk object's property from a thread by jimicarlo
in thread How to change a Tk object's property from a thread by santi_h87

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