Right. So your issue is retrieving a reference to the canvas object. The easiest approach would probably be to store a reference to it when you create it. You seem to be creating a module anyway...so perhaps something like: 
package YourPackage;
use strict;use warnings;
use Tk;
use Tk::Canvas;
sub new {
   my $class = shift;
   my $self = bless {}, $class;
   my $mw = MainWindow->new();
   $self->{'mainwin'}=$mw;
   $self->{'mycanvas'}=$mw->Canvas();
   return $self;
}
sub getcanvas {
   my $self=shift;
   printf "Returning a %s\n",ref($self->{'mycanvas'});
   return $self->{'mycanvas'}
}
package main;
my $YP = YourPackage->new();
my $canvas=$YP->getcanvas();

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In reply to Re^5: Question about embedded Tk::Canvas by kschwab
in thread Question about embedded Tk::Canvas by emilbarton

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