I seem to recall some ways to try to influence where the dialog box appears, but the X window manager can interfere in ways you may have a hard time controlling. Since the dialog box is going to appear in a new top level window, its placement is less under your control.

You need the -geometry option, which is described here:
http://www.wellho.net/forum/The-Tcl-programming-language/Tk-Geometry-strings.html

To be able to place a dialog on top of another window, you'll need to use the winfo command to get the information. In Perl, you'll want to do something like:
$mw->winfo("geometry")

See all possible winfo strings here: http://www.wellho.net/forum/The-Tcl-programming-language/Tk-Geometry-strings.html

Hello,

Thank you for your answer. To get the geometry information via winfo is working fine. So it is no problem to compute the geometry information I need to place the dialogbox in the middle of the main window.

My problem is how can I set the geometry information to the dialogbox?

I tried the following code:

my $db = $mw->DialogBox(-title => "Status", -buttons => ['Cancel'], -geometry => "300x300x+100+100");

I got this error:

Tk::Error: Can't set -geometry to `300x300x+100+100' for Tk::DialogBox
+=HASH(0x1d85574): unknown option "-geometry" at c:/Perl/site/lib/Tk/C
+onfigure.pm line 46.
 at c:/Perl/site/lib/Tk/Derived.pm line 294
[download]

Thank you for your help.

Greetings,

Dirk

You can't easily affect the geometry of the DialogBox directly since it isn't visible until you Show() it... and doesn't return control until the Show() is done. You CAN pass parameters to the Show() method to affect how it is displayed however. It uses Tk::Popup internally to display. Check the documentation of Popup for details.

use warnings;
use strict;
use Tk;
use Tk::DialogBox;

my $mw = MainWindow->new;

my $db = $mw->DialogBox( -title => 'Status', -buttons => ['Ok', 'Cance
+l'] );
print $db->Show( -popover => $mw, -overanchor => 'c', -popanchor  => '
+c' );
MainLoop;
[download]

This is the perfect hint. Thanks.