$top->title("Diagram Viewer");
$top->configure(-background => 'white');

#<a menu bar at the top>...skipping some details
my $menu_bar = $top->Frame()->pack(-side => 'top', -fill => 'x');

#skipping adding buttons to menu_bar....

# the next frames

my $top_canvas_frame = $top->Frame()->packAdjust(-side => 'top', -expand => 'both', -fill => 'both');

my $bottom_canvas_frame = $top->Frame()->pack(-side => 'bottom', -expand => 'both', -fill => 'both');

my $blankCanvas = { canvas => newCanvas($top_canvas_frame)};

# here is where I can't figure out a way to insert another view $blankCanvas into $bottom_canvas_frame so we can get dual views...
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