You are not assigning a value to $p1 in the second button, and you're not passing an argument to &test in the first button. Forgot about the [ .. ] construct in Tk, see above for actual problem. this is why i always use sub { ... } callbacks in Tk, though.

I think you want

$mw->Button(
  -text => 'func',
  -command =>  sub { test($jcb->getSelectedValue($jcb->getSelectedInde
+x())) } ,
)->pack;

$mw->Button(
  -text => 'embed',
  -command =>  sub { my $p1 = $jcb->getSelectedIndex(); printf("e: \$p
+1 = >>$p1<<\n"); } 
)->pack;
[download]