Somewhere in Main application call the dirtree_sub below to choose a working area. Once user select the work area through dirtree, it will set the path in $area entry box. But when I add $dirtree_frame->destroy in dirtree_sub below, it print warning: 

Useless use of reference constructor in void context at geometry_place
+.pl line 564.
Useless use of reference constructor in void context at geometry_place
+.pl line 570.

[download]

Any idea how to solve this?

Some code in main application: 

my $area = $mw->Entry(-background => "white", -foreground => "black", 
+-width => 51)->place(-x=>100, -y=>$ystart + 60);
$area->insert('end', "$workarea");


sub dirtree_sub {
    
    if ($area->get() ne "") {
        $CWD = $area->get();
    } else {
        $CWD = Cwd::cwd();
    };

    my $dirtree_frame = $mw->Toplevel;
    $dirtree_frame->title("Select work area");

    my $DIR_TREE = $dirtree_frame->Scrolled('DirTree',
                                 -scrollbars => "osoe",
                                 -width => 50,
                                 -height => 25,
                                 -exportselection => 1,
                                 -browsecmd => sub {$CWD = shift},
                                 -command   => sub {\&show_cwd(); $dir
+tree_frame->destroy})->pack(-fill => "both",
                                                                 -expa
+nd => 1);

    $DIR_TREE->chdir($CWD);

    my $button_frame = $dirtree_frame->Frame()->pack(-side => "bottom"
+);
    $button_frame->Button(-text => "Ok",
                          -command => sub {\&show_cwd(); $dirtree_fram
+e->destroy})->pack(-side => "left");
    $button_frame->Button(-text => "Exit",
                          -command => [$dirtree_frame=>'destroy'])->pa
+ck(-side => "left");

};

sub show_cwd {


  $area->delete('0.0', 'end');
  $area->insert('end', $CWD);


}

[download]

In reply to Useless use of reference constructor in void context by myfamilygeneral

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