It would be most helpful if you could post your current code.

I presume you can get this far...

#button 3 is "right click"
$someWidget->bind('<3>', 
    sub {
          my $widget = shift;
          print "right button clicked! Pop up menu now\n"; 
          #run methods on $widget
          my $Ev = $widget->XEvent;
          #stuff is learned here...
          #then new window is generated
         });
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Basically to get the "right button, #3" to work, you have to "bind" this button to the Tk object. Show some code and we shall work on it.