Tags are the most beautiful aspect of the Canvas. This should show you how it's done. :-) 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $top = new MainWindow;

my $c=$top->Canvas->pack;

my $circle = $c->createOval(30,30,100,100,
               -fill => 'blue',  
               -tags =>['circle'],
               -stipple => 'gray12',
          );

my $rect1 = $c->createRectangle(10,10,44,44,
               -fill => 'green',  
               -stipple => 'gray12',
               -tags =>['rect1'],
              );


my $rect2 = $c->createRectangle(93,93,200,200,
               -fill => 'yellow',  
               -tags =>['rect2'],
               -stipple => 'gray12',
           );

my $poly1 = $c->createPolygon(0,0, 44,44, 55,55, 90,90, 200,200, 10,10
+0,0,0,
                    -fill => 'red',
            -smooth => 1,       
                    -splinesteps => 100,
            -stipple => 'gray12',
            -tags =>['poly1'],
            );

$c->Tk::bind("<Motion>", [ \&print_xy, Ev('x'), Ev('y') ]);

$c->CanvasBind('<B1-ButtonRelease>', [ \&add_something, Ev('x'), Ev('y
+') ]); 

&print_xy($c, 42,42);

MainLoop;

sub print_xy {
  my ($canv, $x, $y) = @_;
 print "(x,y) = ", $canv->canvasx($x), ", ", $canv->canvasy($y), "\n";
#my $x1 = $x+1;
#my $y1 = $y+1;
#it will actually use a zero size rectangle
my (@current) = $canv->find('overlapping', $x, $y, $x, $y);

foreach my $id(@current){ 
    print $canv->gettags($id),' ';
 }
print "\n";

}


sub add_something {
  my ($canv, $x, $y) = @_;
 print "(x,y) = ", $canv->canvasx($x), ", ", $canv->canvasy($y), "\n";

my $current = $canv->find(qw/withtag current/);
$canv->addtag('aTimeTag'.time, 'withtag', $current);

print join ' ', $canv->gettags($current);
print "\n";

}

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

In reply to Re: Determine canvas object under click (Tk) by zentara
in thread Determine canvas object under click (Tk) by perldough

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