Here's an example that works: 

#!/usr/bin/perl -w
use Tk;

my $mw = MainWindow->new(-title=>"Demo");

my $HlpBttn = $mw->Button(-text=>"Make NEW Window", -command=> sub { m
+ake_win(); });
                       
$HlpBttn->pack(-padx =>60, -pady =>10);

MainLoop;

sub make_win 
{
    my $win = $mw->Toplevel(-title=>'new window');

    my $Bttn = $win->Button(-text=>"CLOSE this window",
                       -command=> sub { close_win($win); }
                   )->pack(-padx =>60, -pady =>10); 
}

sub close_win
{
    my $thiswin = $_[0];
    $thiswin->destroy;
}

[download]

make_win creates a closure in the -command option, creating an anonymous subref that carries around with it an instance of $win. When the "CLOSE this window" button is pressed in a given window, the coderef that is exectuted uses the instance of $win that it carries with it.

Actually, I could have just said $win->Button(yada-yada...-command=> sub { $win->destroy })....

Note that for either way to work, $win must be a lexical, outside the scope of the anonymous coderef.

--Bob Niederman, http://bob-n.com

All code given here is UNTESTED unless otherwise stated.

In reply to Re: Functions and Tk by bobn
in thread Functions and Tk by surrealistfashion

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