$tree-> = $pane->Tree(
   -width		=> 30,
   -height		=> 1500,
   -itemtype 		=> 'window',
   -relief             	=> 'flat',
   -borderwidth        	=> 0,
   -selectborderwidth	=> 0
)->grid(
   -row 		=> $row,
   -column 		=> 0,
   -columnspan		=> 2,
   -sticky		=> 'w'
);

##</code><code>##

my $ref1 = $tree->Label(
   -text 		=> $_,
   -anchor 		=> 'w'
);
$tree->add(
   $_,
   -window		=> $ref1
);

##</code><code>##

my $ref2 = $tree->Checkbutton(
   -text 		=> $_, 
   -variable 		=> \$var,
   -anchor 		=> 'w'
);
$tree->add(
   $parent.'.'.$column,
   -window			=> $ref2
);